W3LPL Propagation forecast

[4L5A]

Some of the best Solar Maximum HF propagation of Solar Cycle 25 is likely to continue through at least Friday.



HF propagation crossing low, mid and high latitudes is likely to be normal through at least Friday.



40 meter DX propagation is likely from early evening until after sunrise.

30 meter DX propagation is likely from late afternoon until a few hours after sunrise.

20, 17 and 15 meter DX propagation is likely 24 hours per day.

12 meter DX propagation is likely from sunrise through late night hours.

10 meter DX propagation is likely from early morning through early night hours.

This forecast derived from today 's NOAA/SWPC web pages and 15 other online sources (the URLs at the end of this forecast) is published five days a week (M-F) in The Daily DX .

All days and times in this forecast are in UTC (Zulu) time.



Global 6 meter above-the-MUF F2 propagation is possible by late October if solar flux values persist well above 200 for several days. 6 meter Trans-Equatorial F2 Propagation (TEP) is likely almost every day from the southern tier of U.S. states through early November. More northerly mid-latitude locations need an unreliable and infrequent additional sporadic-E hop or an occasional above-the-MUF mid-latitude F2 hop. 6 meter sporadic-E propagation beyond 2200 km is extremely unlikely until December.

The 2300Z Penticton 10.7 cm observed solar flux index was 260 and is likely to remain about the same through at least Friday.
SILSO’s latest Estimated International Sunspot Number was 211 and is likely to remain about the same through Friday.
The visible solar disk has one rapidly growing large active region, one growing medium active region, three growing small active regions, two decaying small active regions, and one decaying very small active region. Total sunspot area is 840 micro solar hemispheres (about five times the surface area of the Earth).

Solar wind speed is likely to improve to near background levels of less than 400 km/second through Friday.



We are in the equinox season when geomagnetically disturbed days occur about twice as often as during the solstice seasons . Quiet geomagnetic conditions are likely through Friday.


M-class solar flares are likely to cause occasional periods of a few minutes of minor to moderate radio blackouts of propagation paths crossing the sunlit side of the Earth through Friday.



There is a chance that X1-class or stronger solar flares may cause radio blackouts of about one hour duration or more on propagation paths crossing the sunlit side of the Earth through Friday.

No S1-class minor solar energetic particle radiation storms that slightly degrade propagation crossing the northern polar region are expected through Friday.

160 and 80 meter propagation from North America to VK/ZL and the South Pacific is likely to be normal through at least Friday . 160 and 80 meter long distance propagation in the northern hemisphere is always mildly to moderately degraded through September by E region blanketing of low angle F2 propagation until at least several hours after sunset.



40 meter short path propagation from North America to the Middle East and south Asia after 2300Z is likely to be normal through at least Friday. Short path propagation between North America and east Asia after about 0900Z is likely to be normal through at least Friday.


30 meter propagation crossing the auroral ovals and polar regions is likely to be normal through at least Friday. Daytime 30 meter long distance propagation is always mildly to moderately degraded within several hours of local noon by E-region blanketing of low angle long distance F2 propagation.

20 meter propagation crossing the auroral ovals and polar regions is likely to be normal through at least Friday. 20 meter propagation beyond 2200 km in the low latitude northern hemisphere is likely to be mildly degraded during midday hours through at least October due to E-region blanketing of low angle F2 propagation.


17 and 15 meter propagation crossing the auroral ovals and polar regions is likely to be normal through at least Friday. 17 and 15 meter long path propagation from North America to southeast and east Asia from about 1100Z to 1400Z is likely to be normal through at least Friday.



12 and 10 meter propagation is likely to be normal through at least Friday. 12 and 10 meter long path propagation from North America to southeast and east Asia from about 1100Z to 1400Z is likely to be normal through at least Friday.



There is a very slight chance of above-the-MUF 6 meter F2 propagation over Africa from the southern tier of US states to the Indian Ocean, equatorial and southern Africa (e.g., 3B8. 3B9, 7Q, D2, FR, V5, ZD7, ZD9 and ZS) from about 1400-1800Z. Trans-equatorial F2 propagation (TEP) is likely from the southern tier of U.S. states to South America from about 2000-0200Z or later. There is a slight chance of above-the-MUF oblique-TEP F2 propagation from the southern tier of U.S. states to the south Pacific (e.g., 3D2, 5W, E5, FK, FO, VK4, VP6 and ZL) from about 1900-0300Z. There is a slight chance that more northerly U.S. stations may couple into TEP and oblique-TEP via unreliable, geographically focused, brief intervals of sporadic-E or unlikely above-the-MUF mid-latitude F2 propagation. There is a chance of TEP propagation from about 2000-0200Z during the initial phase of strong to severe geomagnetic storms then degrading several hours after initial enhancement.

Sustained southward orientation (-Bz) of the north-south component of the interplanetary magnetic field (IMF) plays a crucial but unpredictable role in triggering all geomagnetic storms. Brief minor to moderate geomagnetic

storms may be gradually triggered when the IMF is sustained in a southward orientation (-Bz) with IMF field strength of about 5 nanoteslas or more for at least a few hours coincident with the influence of a geoeffective coronal hole high speed stream or CME. More frequent, longer duration, minor to severe geomagnetic storms may be triggered suddenly and unpredictably when the IMF is sustained in a southward orientation (-Bz) with IMF field strength of about 5 nanoteslas or more for a period of several hours or more coincident with the influence of a geoeffective CME and solar wind speed of about 500 km/second or more.



Mid-latitude northern hemisphere sunrise is 9 minutes later and sunset is 16 minutes earlier than it was on September 22nd . Sunrise is about two hours earlier and sunset is about two hours later at the altitude of the refracting F2 region. Sunrise is about one hour earlier, and sunset is about one hour later at the altitude of the daytime absorbing D region.

[4L5A]

Propagation crossing low latitudes is likely to be normal through at least Thursday.




Propagation crossing midlatitudes is likely to be normal through early Wednesday, mostly normal during midday Wednesday, then improving to normal through late Thursday.



Propagation crossing high latitudes is likely to be mostly normal through early Wednesday, mildly to moderately degraded during midday Wednesday, then improving to mostly normal through late Thursday.




40 meter DX propagation is likely from early evening until after sunrise.

30 meter DX propagation is likely from late afternoon until a few hours after sunrise.

20, 17 and 15 meter DX propagation is likely 24 hours per day.

12 meter DX propagation is likely from sunrise through late night hours.

10 meter DX propagation is likely from early morning through early night hours.

This forecast derived from today 's NOAA/SWPC web pages and 15 other online sources (the URLs at the end of this forecast) is published five days a week (M-F) in The Daily DX .

All days and times in this forecast are in UTC (Zulu) time.



Global 6 meter F2 propagation may begin in late October if solar flux values persist well above 200. 6 meter Trans-Equatorial F2 Propagation (TEP) is likely to occur regularly from the southern tier of US states from September through early November. More northerly mid-latitude locations need an infrequent additional sporadic-E hop or an above-the-MUF mid-latitude F2 hop. 6 meter sporadic-E propagation beyond 2200 km is extremely unlikely until December.



The 2300Z Penticton 10.7 cm observed solar flux index was 168 and is likely to remain about the same through Thursday.


SILSO’s latest Estimated International Sunspot Number was 128 and is likely to remain about the same through Thursday.


The visible solar disk has one growing medium active region, one stable medium active region, one growing small active region, three stable small active regions and two declining small active regions containing 44 sunspots with a total sunspot area of 690 micro solar hemispheres (about four times the surface area of the Earth).

There is a chance that M-class solar flares may cause a few minutes of minor to moderate radio blackouts of propagation paths crossing the sunlit side of the Earth through Thursday.



No X1-class solar flares are likely to cause longer lasting blackouts of propagation paths crossing the sunlit side of the Earth through Thursday.

No S1-class minor solar energetic particle radiation storms that slightly degrade propagation crossing the northern polar region are expected through Thursday.

160 and 80 meter propagation from North America to VK/ZL and the South Pacific is likely to be normal through at least Thursday . 160 and 80 meter long distance propagation in the northern hemisphere is always mildly to moderately degraded through September by E region blanketing of low angle F2 propagation until at least several hours after sunset.



40 meter short path propagation from North America to the Middle East and south Asia after 2300Z is likely to be mostly normal on Tuesday, mildly degraded on Wednesday and mostly normal on Friday. Short path propagation between North America and east Asia after about 0900Z is likely to be mildly to moderately disturbed on Tuesday and Wednesday, improving to normal on Thursday.


30 meter propagation crossing the auroral ovals and polar regions is likely to be mostly normal through early Wednesday, mildly to moderately degraded during midday Wednesday, then improving to mostly normal through late Thursday. Daytime 30 meter long distance propagation is always mildly to moderately degraded within several hours of local noon by E-region blanketing of low angle long distance F2 propagation.

20 meter propagation crossing the auroral ovals and polar regions is likely to be mostly normal through early Wednesday, mildly to moderately degraded during midday Wednesday, then improving to mostly normal through late Thursday. 20 meter propagation beyond 2200 km in the low latitude northern hemisphere is likely to be mildly degraded during midday hours through at least October due to E-region blanketing of low angle F2 propagation.


17 and 15 meter propagation crossing the auroral ovals and polar regions is likely to be mostly normal through early Wednesday, mildly to moderately degraded during midday Wednesday, then improving to mostly normal through late Thursday . 17 and 15 meter long path propagation from North America to southeast and east Asia from about 1100Z to 1400Z is likely to be mostly normal on Tuesday, mildly to moderately degraded Wednesday and normal on Thursday.



12 and 10 meter propagation is likely to be mostly normal through early Wednesday, mildly to moderately degraded during midday Wednesday, then improving to mostly normal through late Thursday . 12 and 10 meter long path propagation from North America to southeast and east Asia from about 1100Z to 1400Z is likely to be mostly normal on Tuesday, mildly to moderately degraded Wednesday and normal on Thursday.



There is a very slight chance of above-the-MUF 6 meter F2 propagation over Africa from the southern tier of US states to the Indian Ocean, equatorial and southern Africa (e.g., 3B8. 3B9, 7Q, D2, FR, V5, ZD7, ZD9 and ZS) from about 1400-1800Z. There is a chance of trans-equatorial F2 propagation (TEP) from the southern tier of U.S. states to South America from about 2000-0200Z. There is a slight chance of above-the-MUF oblique-TEP F2 propagation from the southern tier of US states to the south Pacific (e.g., 3D2, 5W, E5, FK, FO, VK4, VP6 and ZL) from about 1900-0300Z. There is a slight chance that more northerly U.S. stations may couple into TEP and oblique-TEP via geographically focused brief intervals of sporadic-E or unlikely above-the-MUF mid-latitude F2 propagation. There is a chance of TEP propagation from about 2000-0200Z during the initial phase of strong to severe geomagnetic storms then degrading several hours after initial enhancement.

Sustained southward orientation (-Bz) of the north-south component of the interplanetary magnetic field (IMF) plays a crucial but unpredictable role in triggering all geomagnetic storms. Brief minor to moderate geomagnetic

storms may be gradually triggered when the IMF is sustained in a southward orientation (-Bz) with IMF field strength of about 5 nanoteslas or more for at least a few hours coincident with the influence of a geoeffective coronal hole high speed stream or CME. More frequent, longer duration, minor to severe geomagnetic storms may be triggered suddenly and unpredictably when the IMF is sustained in a southward orientation (-Bz) with IMF field strength of about 5 nanoteslas or more for a period of several hours or more coincident with the influence of a geoeffective CME and solar wind speed of about 500 km/second or more.



Mid-latitude northern hemisphere sunrise is two minutes later and sunset is three minutes earlier than it was on September 22nd . Sunrise is about two hours earlier and sunset is about two hours later at the altitude of the refracting F2 region. Sunrise is about one hour earlier, and sunset is about one hour later at the altitude of the daytime absorbing D region.

[4L5A]

Propagation crossing low and mid latitudes is likely to be normal through at least Saturday.



Propagation crossing high latitudes is likely to be mostly normal through Saturday



40 meter DX propagation is likely from early evening until after sunrise.

30 meter DX propagation is likely from late afternoon until a few hours after sunrise.

20, 17 and 15 meter DX propagation is likely 24 hours per day.

12 meter DX propagation is likely from sunrise through late night hours.

10 meter DX propagation is likely from mid-morning through early night hours.

This forecast derived from today 's NOAA/SWPC web pages and 15 other online sources (the URLs at the end of this forecast) is published five days a week (M-F) in The Daily DX .

All days and times in this forecast are in UTC (Zulu) time.



Global 6 meter F2 propagation may begin in late October if solar flux values persist well above 200. 6 meter Trans-Equatorial F2 Propagation (TEP) is likely to occur regularly from the southern tier of US states from September through early November. More northerly mid-latitude locations need an infrequent additional sporadic-E hop or an infrequent above-the-MUF mid-latitude F2 hop. 6 meter sporadic-E propagation beyond 2200 km is extremely unlikely until December.



The 2300Z Penticton 10.7 cm observed solar flux index was 159 and is likely to remain about the same through Saturday.


SILSO’s latest Estimated International Sunspot Number was only 87 and is likely to remain about the same or slightly higher through Saturday.

The visible solar disk has two growing medium solar active regions, one stable medium solar active region, one decaying medium active region and one decaying small solar active region containing 46 sunspots with a total sunspot area of 580 micro solar hemispheres (about four times the surface area of the Earth).

Solar wind speed is likely to be 400 km/second or less through at least Saturday.



Quiet to unsettled geomagnetic conditions are likely through late Thursday then improving to mostly quiet conditions through midday Saturday and slightly degrading to quiet to unsettled conditions through at least late Saturday

M-class solar flares are likely to cause a few minutes of minor to moderate radio blackouts of propagation paths crossing the sunlit side of the Earth through Saturday. There is a slight chance that X-class solar flares may cause about an hour of widespread blackouts of propagation paths crossing the sunlit side of the Earth through Saturday.

There is a slight chance of S1-class solar energetic particle radiation storms through Thursday slightly degrading propagation crossing the northern polar region.

160 and 80 meter propagation from North America to VK/ZL and the South Pacific is likely to be normal through at least Saturday . 160 and 80 meter long distance propagation in the northern hemisphere is always mildly to moderately degraded through September by E region blanketing of low angle F2 propagation until at least several hours after sunset.



40 meter short path propagation from North America to the Middle East and south Asia after 2300Z is likely to be normal through at least Saturday. Short path propagation between North America and east Asia after about 0900Z is likely to be mostly normal on Thursday improving to normal on Friday then slightly degrading to mostly normal on Saturday.


30 meter propagation crossing the auroral ovals and polar regions is likely to be mostly normal on Thursday, improving to normal on Friday then slightly degrading to mostly normal on Saturday. Daytime 30 meter long distance propagation is always mildly to moderately degraded within several hours of local noon by E-region blanketing of low angle long distance F2 propagation.

20 meter propagation crossing the auroral ovals and polar regions is likely to be mostly normal on Thursday, improving to normal on Friday then slightly degrading to mostly normal on Saturday.. 20 meter propagation beyond 2200 km in the northern hemisphere is likely to be mildly degraded at low latitudes through at least October due to E-region blanketing of low angle F2 propagation.


17 and 15 meter propagation crossing the auroral ovals and polar regions is likely to be mostly normal on Thursday, improving to normal on Friday then slightly degrading to mostly normal on Saturday. 17 and 15 meter long path propagation from North America to southeast and east Asia from about 1100Z to 1400Z is likely to be mostly normal on Thursday, improving to normal on Friday then slightly degrading to mostly normal on Saturday.



12 and 10 meter propagation is likely to be mostly normal on Thursday, improving to normal on Friday then slightly degrading to mostly normal on Saturday. 12 and 10 meter long path propagation from North America to southeast and east Asia from about 1100Z to 1400Z is likely to be mostly normal on Thursday, improving to normal on Friday then slightly degrading to mostly normal on Saturday.



There is a very slight chance of above-the-MUF 6 meter F2 propagation over Africa from the southern tier of US states to the Indian Ocean, equatorial and southern Africa (e.g., 3B8. 3B9, 7Q, D2, FR, V5, ZD7, ZD9 and ZS) from about 1400-1800Z. There is a chance of trans-equatorial F2 propagation (TEP) from the southern tier of U.S. states to South America from about 2000-0200Z. There is a slight chance of above-the-MUF oblique-TEP F2 propagation from the southern tier of US states to the south Pacific (e.g., 3D2, 5W, E5, FK, FO, VK4, VP6 and ZL) from about 1900-0300Z. There is a slight chance that more northerly U.S. stations may couple into TEP and oblique-TEP via geographically focused brief intervals of sporadic-E or unlikely above-the-MUF mid-latitude F2 propagation. There is a chance of TEP propagation from about 2000-0200Z during the initial phase of strong to severe geomagnetic storms then degrading several hours after initial enhancement.

Sustained southward orientation (-Bz) of the north-south component of the interplanetary magnetic field (IMF) plays a crucial but unpredictable role in triggering all geomagnetic storms. Brief minor to moderate geomagnetic

storms may be gradually triggered when the IMF is sustained in a southward orientation (-Bz) with IMF field strength of about 5 nanoteslas or more for at least a few hours coincident with the influence of a geoeffective coronal hole high speed stream or CME. More frequent, longer duration, minor to severe geomagnetic storms may be triggered suddenly and unpredictably when the IMF is sustained in a southward orientation (-Bz) with IMF field strength of about 5 nanoteslas or more for a period of several hours or more coincident with the influence of a geoeffective CME and solar wind speed of about 500 km/second or more.



Mid-latitude northern hemisphere sunrise is 71 minutes later and sunset is 89 minutes earlier than it was on June 20th . Sunrise is about two hours earlier and sunset is about two hours later at the altitude of the refracting F2 region. Sunrise is about one hour earlier, and sunset is about one hour later at the altitude of the daytime absorbing D region.

[4L5A]

This forecast is derived from today 's NOAA/SWPC web pages and 15 other online sources (the URLs at the end of this forecast) is published five days a week (M-F) in The Daily DX .

All days and times in this forecast are in UTC (Zulu) time.



Global 6 meter F2 propagation may begin by late October if solar flux values persist well above 200. 6 meter Trans-Equatorial F2 Propagation (TEP) is likely to occur regularly from the southern tier of US states from September through November. More northerly mid-latitude locations need an infrequent additional sporadic-E hop or an F2 hop. 6 meter sporadic-E propagation beyond 2200 km is extremely unlikely until December.



The 2300Z Penticton 10.7 cm observed solar flux index was 165 and is likely to remain about the same through Friday.

SILSO’s latest Estimated International Sunspot Number was 141 and is likely to remain about the same through Friday.

The visible solar disk has two growing medium solar active regions, two stable medium solar active regions and one stable small solar active region containing 70 sunspots with a total sunspot area of 590 micro solar hemispheres (about four times the surface area of the Earth).

Solar wind speed is likely to be 450 km/second or less through early Thursday then improving to 400 km/second or less through at least Friday.



Quiet to unsettled geomagnetic conditions are likely through early Thursday then improving to mostly quiet conditions through at least Friday
There is a slight chance of S1-class solar energetic particle radiation storms through Thursday slightly degrading propagation crossing the northern polar region.

160 and 80 meter propagation from North America to VK/ZL and the South Pacific is likely to be normal through at least Friday . 160 and 80 meter long distance propagation in the northern hemisphere is always mildly to moderately degraded through September by E region blanketing of low angle F2 propagation until at least several hours after sunset.



40 meter short path propagation from North America to the Middle East and south Asia after 2330Z is likely to be normal through at least Friday. Short path propagation between North America and east Asia after about 0900Z is likely to be mostly normal through Friday


30 meter propagation crossing the auroral ovals and polar regions is likely to be mostly normal through early Thursday then improving to normal through at least Friday . Daytime 30 meter long distance propagation is always mildly to moderately degraded within several hours of local noon by E-region blanketing of low angle long distance F2 propagation.

20 meter propagation crossing the auroral ovals and polar regions is likely to be mostly normal through early Thursday then improving to normal through at least Friday . 20 meter propagation beyond 2200 km in the northern hemisphere is likely to be mildly degraded at low latitudes through at least October due to E-region blanketing of low angle F2 propagation.


17 and 15 meter propagation crossing the auroral ovals and polar regions is likely to be mostly normal through early Thursday then improving to normal through at least Friday . 17 and 15 meter long path propagation from North America to southeast and east Asia from about 1100Z to 1400Z is likely to be mostly normal through early Thursday then improving to normal through at least Friday.



12 and 10 meter propagation is likely to be mostly normal through early Thursday then improving to normal through at least Friday . 12 and 10 meter long path propagation from North America to southeast and east Asia from about 1100Z to 1400Z is likely to be mostly normal through early Thursday then improving to normal through at least Friday



There is a slight chance of above-the-MUF 6 meter F2 propagation over Africa from the southern tier of US states to the Indian Ocean, equatorial and southern Africa (e.g., 3B8. 3B9, 7Q, D2, FR, V5, ZD7 and ZS) from about 1400-1800Z. There is a chance of trans-equatorial F2 propagation (TEP) from the southern tier of U.S. states to South America from about 2000-0200Z. There is a slight chance of above-the-MUF oblique-TEP F2 propagation from the southern tier of US states to the south Pacific (e.g., 3D2, 5W, E5, FK, FO, VK4, VP6 and ZL) from about 1900-0300Z. There is a slight chance that more northerly U.S. stations may couple into TEP and oblique-TEP via geographically focused brief intervals of sporadic-E or above-the-MUF F2 propagation. There is a chance of TEP propagation from about 2000-0200Z during the initial phase of strong to severe geomagnetic storms then degrading several hours after initial enhancement.

160 and 80 meter propagation from North America to VK/ZL and the South Pacific is likely to be normal through at least Friday . 160 and 80 meter long distance propagation in the northern hemisphere is always mildly to moderately degraded through September by E region blanketing of low angle F2 propagation until at least several hours after sunset.



40 meter short path propagation from North America to the Middle East and south Asia after 2330Z is likely to be normal through at least Friday. Short path propagation between North America and east Asia after about 0900Z is likely to be mostly normal through Friday


30 meter propagation crossing the auroral ovals and polar regions is likely to be mostly normal through early Thursday then improving to normal through at least Friday . Daytime 30 meter long distance propagation is always mildly to moderately degraded within several hours of local noon by E-region blanketing of low angle long distance F2 propagation.

20 meter propagation crossing the auroral ovals and polar regions is likely to be mostly normal through early Thursday then improving to normal through at least Friday . 20 meter propagation beyond 2200 km in the northern hemisphere is likely to be mildly degraded at low latitudes through at least October due to E-region blanketing of low angle F2 propagation.


17 and 15 meter propagation crossing the auroral ovals and polar regions is likely to be mostly normal through early Thursday then improving to normal through at least Friday . 17 and 15 meter long path propagation from North America to southeast and east Asia from about 1100Z to 1400Z is likely to be mostly normal through early Thursday then improving to normal through at least Friday.



12 and 10 meter propagation is likely to be mostly normal through early Thursday then improving to normal through at least Friday . 12 and 10 meter long path propagation from North America to southeast and east Asia from about 1100Z to 1400Z is likely to be mostly normal through early Thursday then improving to normal through at least Friday



There is a slight chance of above-the-MUF 6 meter F2 propagation over Africa from the southern tier of US states to the Indian Ocean, equatorial and southern Africa (e.g., 3B8. 3B9, 7Q, D2, FR, V5, ZD7 and ZS) from about 1400-1800Z. There is a chance of trans-equatorial F2 propagation (TEP) from the southern tier of U.S. states to South America from about 2000-0200Z. There is a slight chance of above-the-MUF oblique-TEP F2 propagation from the southern tier of US states to the south Pacific (e.g., 3D2, 5W, E5, FK, FO, VK4, VP6 and ZL) from about 1900-0300Z. There is a slight chance that more northerly U.S. stations may couple into TEP and oblique-TEP via geographically focused brief intervals of sporadic-E or above-the-MUF F2 propagation. There is a chance of TEP propagation from about 2000-0200Z during the initial phase of strong to severe geomagnetic storms then degrading several hours after initial enhancement.

Sustained southward orientation (-Bz) of the north-south component of the interplanetary magnetic field (IMF) plays a crucial but unpredictable role in triggering all geomagnetic storms. Brief minor to moderate geomagnetic

storms may be gradually triggered when the IMF is sustained in a southward orientation (-Bz) with IMF field strength of about 5 nanoteslas or more for at least a few hours coincident with the influence of a geoeffective coronal hole high speed stream or CME. More frequent, longer duration, minor to severe geomagnetic storms may be triggered suddenly and unpredictably when the IMF is sustained in a southward orientation (-Bz) with IMF field strength of about 5 nanoteslas or more for a period of several hours or more coincident with the influence of a geoeffective CME and solar wind speed of about 500 km/second or more.



Mid-latitude northern hemisphere sunrise is 70 minutes later and sunset is 87 minutes earlier than it was on June 20th . Sunrise is about two hours earlier and sunset is about two hours later at the altitude of the refracting F2 region. Sunrise is about one hour earlier, and sunset is about one hour later at the altitude of the daytime absorbing D region.

[4L5A]

Some of the best summer solar maximum propagation of Solar Cycle 25 is likely to continue through at least Friday.



Propagation crossing low and mid latitudes is likely to be normal through at least Friday



Propagation crossing high latitudes is likely to be mostly normal on Wednesday then improving to normal through least Friday.



40 meter DX propagation is likely from early evening until after sunrise.

30 meter DX propagation is likely from late afternoon until a few hours after sunrise.

20, 17 and 15 meter DX propagation is likely 24 hours per day.

12 meter DX propagation is likely from sunrise through late night hours.

10 meter DX propagation is likely from mid-morning through early night hours.


This forecast derived from today 's NOAA/SWPC web pages and 15 other online sources (the URLs at the end of this forecast) is published five days a week (M-F) in The Daily DX .

All days and times in this forecast are in UTC (Zulu) time.



Global 6 meter F2 propagation may begin by late October if solar flux values continue to persist well above 200. 6 meter Trans-Equatorial F2 Propagation (TEP) is likely to occur regularly from the southern tier of US states from September through November. More northerly mid-latitude locations need an unlikely additional sporadic-E or a more likely an F2 hop. 6 meter sporadic-E propagation beyond 2200 km is extremely unlikely until December.



The 2300Z Penticton 10.7 cm observed solar flux index was 238 and is likely to remain about the same through Friday.


SILSO’s latest Estimated International Sunspot Number was 177 and is likely to remain about the same through Friday.

The visible solar disk has one growing large solar active region, one growing medium solar active region, one stable medium solar active region, one decaying medium solar active region, one decaying small solar active region and two decaying very small solar active regions containing 100 sunspots with a total sunspot area of 1500 micro solar hemispheres (about nine times the surface area of the Earth). solar active regions will be rotating onto the visible solar disk over the next several days.

Solar wind speed is likely to be 450 km/second or less on Wednesday then improving to 400 km/second or less through at least Friday.



Quiet to unsettled geomagnetic conditions are likely on Wednesday then improving to quiet conditions through at least Friday.

M-class solar flares are likely to cause a few minutes of minor to moderate radio blackouts of propagation paths crossing the sunlit side of the Earth through Friday. There is a chance that X-class solar flares may cause about an hour of widespread blackouts of propagation paths crossing the sunlit side of the Earth through Friday.

S1-class solar energetic particle radiation storms are likely on Wednesday having a slight effect on propagation crossing the northern polar region. There is a slight chance of S1-class solar energetic particle radiation storms on Thursday and Friday.

160 and 80 meter propagation from North America to VK/ZL and the South Pacific is likely to be normal through at least Friday . 160 and 80 meter long distance propagation in the northern hemisphere is always mildly to moderately degraded through September by E region blanketing of low angle F2 propagation until at least several hours after sunset.



40 meter short path propagation from North America to the Middle East and south Asia after 0030Z is likely to be mostly normal on Thursday improving to normal through at least Friday. Short path propagation between North America and east Asia after about 0930Z is likely to be mostly normal on Wednesday then improving to normal through at least Friday,


30 meter propagation crossing the auroral ovals and polar regions is likely to be mostly normal on Wednesday then improving to normal through at least Friday . Daytime 30 meter long distance propagation is always mildly to moderately degraded within several hours of local noon by E-region blanketing of low angle F2 propagation.

20 meter propagation crossing the auroral ovals and polar regions is likely to be mostly normal on Wednesday then improving to normal through at least Friday . 20 meter propagation beyond 2200 km in the northern hemisphere is likely to be mildly degraded through mid-September within several hours of local noon at more northerly mid latitudes, moderately degraded through late September at mid- latitudes , more severely degraded through October at more southerly mid-latitudes and severely degraded at low latitudes through at least October due to E-region blanketing of low angle F2 propagation.


17 and 15 meter propagation crossing the auroral ovals and polar regions is likely to be mostly normal on Wednesday then improving to normal through at least Friday . 17 and 15 meter long path propagation from North America to southeast and east Asia from about 1100Z to 1400Z is likely to be mostly normal on Wednesday then improving to normal through at least Friday.



12 and 10 meter propagation is likely to be mostly normal on Wednesday then improving to normal through at least Friday . 12 and 10 meter long path propagation from North America to southeast and east Asia from about 1100Z to 1400Z is likely to be mostly normal on Wednesday then improving to normal through at least Friday



Thermally driven high velocity seasonal thermospheric winds at F2 region altitude blow from the high temperature dayside hemisphere to the lower temperature nightside hemisphere reducing the volume of neutral atomic oxygen available to be ionized in the F2 region during daytime hours, lowering the MUF for F2 propagation crossing high latitudes to mostly less than 28 MHz and degrading the duration and reliability of 10 meter DX propagation crossing high latitudes until about mid-September.



There is a slight chance of above-the-MUF 6 meter F2 propagation over Africa from the southern tier of US states to the Indian Ocean, equatorial and southern Africa (e.g., 3B8. 3B9, 7Q, D2, FR, V5, ZD7 and ZS) from about 1400-1800Z. There is a chance of trans-equatorial F2 propagation (TEP) from the southern tier of U.S. states to South America from about 2000-0200Z. There is a slight chance of above-the-MUF oblique-TEP F2 propagation from the southern tier of US states to the south Pacific (e.g., 3D2, 5W, E5, FK, FO, VK4, VP6 and ZL) from about 1900-0300Z. There is a slight chance that more northerly U.S. stations may couple into TEP and oblique-TEP via geographically focused brief intervals of sporadic-E or above-the-MUF F2 propagation. There is a chance of TEP propagation from about 2000-0200Z during the initial phase of strong to severe geomagnetic storms then degrading several hours after initial enhancement.

Sustained southward orientation (-Bz) of the north-south component of the interplanetary magnetic field (IMF) plays a crucial but unpredictable role in triggering all geomagnetic storms. Brief minor to moderate geomagnetic

storms may be gradually triggered when the IMF is sustained in a southward orientation (-Bz) with IMF field strength of about 5 nanoteslas or more for at least a few hours coincident with the influence of a geoeffective coronal hole high speed stream or CME. More frequent, longer duration, minor to severe geomagnetic storms may be triggered suddenly and unpredictably when the IMF is sustained in a southward orientation (-Bz) with IMF field strength of about 5 nanoteslas or more for a period of several hours or more coincident with the influence of a geoeffective CME and solar wind speed of about 500 km/second or more.



Mid-latitude northern hemisphere sunrise is 54 minutes later and sunset is 61 minutes earlier than it was on June 20th . Sunrise is about two hours earlier and sunset is about two hours later at the altitude of the refracting F2 region. Sunrise is about one hour earlier, and sunset is about one hour later at the altitude of the daytime absorbing D region.

[4L5A]

Some of the best summer solar maximum propagation of Solar Cycle 25 is likely to continue through at least Thursday.



Propagation crossing low and mid latitudes is likely to be normal through at least Thursday



Propagation crossing high latitudes is likely to be mildly degraded through Wednesday improving to normal through at least Thursday



40 meter DX propagation is likely from early evening until after sunrise.

30 meter DX propagation is likely from late afternoon until a few hours after sunrise.

20, 17 and 15 meter DX propagation is likely 24 hours per day.

12 meter DX propagation is likely from early morning until late night hours,

10 meter DX propagation is likely from mid-morning through early night hours.

This forecast derived from today 's NOAA/SWPC web pages and 15 other online sources (the URLs at the end of this forecast) is published five days a week (M-F) in The Daily DX .

All days and times in this forecast are in UTC (Zulu) time.



Global 6 meter F2 propagation may begin by late October if solar flux values continue to persist well above 200. 6 meter Trans-Equatorial F2 Propagation (TEP) is likely to occur regularly from the southern tier of US states from September through November. More northerly locations need an unlikely additional sporadic-E or F2 hop. 6 meter sporadic-E propagation beyond 2200 km is extremely unlikely until December.



The 2300Z Penticton 10.7 cm observed solar flux index was 236 and is likely to remain about the same through Thursday.

SILSO’s latest Estimated International Sunspot Number was 172 and is likely to remain about the same through Thursday.

The visible solar disk has one growing large solar active region, one decaying large solar region, one growing medium solar active region, one stable medium solar active region, one decaying small solar active region, one stable very small solar active region and two decaying very small solar active regions containing 100 sunspots with a total sunspot area of 1500 micro solar hemispheres (about nine times the surface area of the Earth). Three solar active regions will be rotating onto the visible solar disk over the next several days.

Solar wind speed is likely to be 500 km/second or less through Wednesday improving to 400 km/second or less through at least Thursday.



Quiet to unsettled geomagnetic conditions are likely through Wednesday improving to quiet conditions through at least Thursday.


M-class solar flares are likely to cause a few minutes of minor to moderate radio blackouts of propagation paths crossing the sunlit side of the Earth through Thursday. There is a chance that X-class solar flares may cause about an hour of widespread blackouts of propagation paths crossing the sunlit side of the Earth through Thursday.

There is a chance of S1-class solar energetic particle radiation storms through Thursday having a slight effect on propagation crossing the northern polar region.

160 and 80 meter propagation from North America to VK/ZL and the South Pacific is likely to be normal through at least Thursday . 160 and 80 meter long distance propagation in the northern hemisphere is always mildly to moderately degraded through September by E region blanketing of low angle F2 propagation until at least several hours after sunset.



40 meter short path propagation from North America to the Middle East and south Asia after 0030Z is likely to be mostly normal through Wednesday improving to normal through at least Thursday. Short path propagation between North America and east Asia after about 0930Z is likely to be mostly normal on Wednesday improving to normal through at least Thursday,


30 meter propagation crossing the auroral ovals and polar regions is likely to be mostly normal through Wednesday improving to normal through at least Thursday . Daytime 30 meter long distance propagation is always mildly to moderately degraded within several hours of local noon by E-region blanketing of low angle F2 propagation.

20 meter propagation crossing the auroral ovals and polar regions is likely to be mostly normal through Wednesday improving to normal through at least Thursday . 20 meter propagation beyond 2200 km in the northern hemisphere is likely to be mildly degraded through mid-September within several hours of local noon at more northerly mid latitudes, moderately degraded through late September at mid- latitudes , more severely degraded through October at more southerly mid-latitudes and severely degraded at low latitudes through at least October due to E-region blanketing of low angle F2 propagation.


17 and 15 meter propagation crossing the auroral ovals and polar regions is likely to be mostly normal through Wednesday improving to normal through at least Thursday . 17 and 15 meter long path propagation from North America to southeast and east Asia from about 1100Z to 1400Z is likely to be mostly normal through Wednesday improving to normal through at least Thursday



12 and 10 meter propagation is likely to be mostly normal through Wednesday improving to normal through at least Thursday . 12 and 10 meter long path propagation from North America to southeast and east Asia from about 1100Z to 1400Z is likely to be mostly normal through Wednesday improving to normal through at least Thursday.



Thermally driven high velocity seasonal thermospheric winds at F2 region altitude blow from the high temperature dayside hemisphere to the lower temperature nightside hemisphere reducing the volume of neutral atomic oxygen available to be ionized in the F2 region during daytime hours, lowering the MUF for F2 propagation crossing high latitudes to mostly less than 28 MHz and degrading the duration and reliability of 10 meter DX propagation crossing high latitudes through about mid-September.



There is a slight chance of above-the-MUF 6 meter F2 propagation over Africa from the southern tier of US states to the Indian Ocean, equatorial and southern Africa (e.g., 3B8. 3B9, 7Q, D2, FR, V5, ZD7 and ZS) from about 1400-1800Z. There is a chance of trans-equatorial F2 propagation (TEP) from the southern tier of U.S. states to South America from about 2000-0200Z. There is a slight chance of above-the-MUF oblique-TEP F2 propagation from the southern tier of US states to the south Pacific (e.g., 3D2, 5W, E5, FK, FO, VK4, VP6 and ZL) from about 1900-0300Z. There is a slight chance that more northerly U.S. stations may couple into TEP and oblique-TEP via geographically focused brief intervals of sporadic-E or above-the-MUF F2 propagation. There is a chance of TEP propagation from about 2000-0200Z during the initial phase of strong to severe geomagnetic storms then degrading several hours after initial enhancement.

Sustained southward orientation (-Bz) of the north-south component of the interplanetary magnetic field (IMF) plays a crucial but unpredictable role in triggering all geomagnetic storms. Brief minor to moderate geomagnetic

storms may be gradually triggered when the IMF is sustained in a southward orientation (-Bz) with IMF field strength of about 5 nanoteslas or more for at least a few hours coincident with the influence of a geoeffective coronal hole high speed stream or CME. More frequent, longer duration, minor to severe geomagnetic storms may be triggered suddenly and unpredictably when the IMF is sustained in a southward orientation (-Bz) with IMF field strength of about 5 nanoteslas or more for a period of several hours or more coincident with the influence of a geoeffective CME and solar wind speed of about 500 km/second or more.



Mid-latitude northern hemisphere sunrise is 53 minutes later and sunset is 59 minutes earlier than it was on June 20th . Sunrise is about two hours earlier and sunset is about two hours later at the altitude of the refracting F2 region. Sunrise is about one hour earlier, and sunset is about one hour later at the altitude of the daytime absorbing D region.

[4L5A]

Some of the best summer solar maximum propagation of Solar Cycle 25 is likely to continue through at least Wednesday.



Propagation crossing all latitudes is likely to be normal through at least Wednesday.



40 meter DX propagation is likely from early evening until after sunrise.

30 meter DX propagation is likely from late afternoon until a few hours after sunrise.

20, 17 and 15 meter DX propagation is likely 24 hours per day.

12 meter DX propagation is likely from early morning until late night hours,

10 meter DX propagation is likely from mid-morning through early night hours.

This forecast derived from today 's NOAA/SWPC web pages and 15 other online sources (the URLs at the end of this forecast) is published five days a week (M-F) in The Daily DX .

All days and times in this forecast are in UTC (Zulu) time.



Global 6 meter F2 propagation may begin by late October if solar flux values continue to persist well above 200. 6 meter Trans-Equatorial F2 Propagation (TEP) is likely to occur regularly from the southern tier of US states from September through November. More northerly locations need an unlikely additional sporadic-E or F2 hop. 6 meter sporadic-E propagation beyond 2200 km is extremely unlikely until December.



The 2300Z Penticton 10.7 cm observed solar flux index was 227 and is likely to remain about the same through Wednesday.


SILSO’s latest Estimated International Sunspot Number was 200 and is likely to remain about the same through Wednesday.

The visible solar disk has one growing large solar active region, one decaying large solar region, one growing medium solar active region, one growing small solar active region, one decaying small solar active region and two very small decaying solar active regions containing 56 sunspots with a total sunspot area of 1560 micro solar hemispheres (about nine times the surface area of the Earth). Four solar active regions will be rotating onto the visible solar disk over the next several days.

Solar wind speed is likely to be 400 km/second or less through at least Wednesday.



Quiet geomagnetic conditions are likely through at least Wednesday.


M-class solar flares are likely to cause a few minutes of minor to moderate radio blackouts of propagation paths crossing the sunlit side of the Earth through Wednesday. There is a slight chance that X-class solar flares may cause about an hour of widespread blackouts of propagation paths crossing the sunlit side of the Earth through Wednesday.

There is a slight chance of S1-class solar energetic particle radiation storms through Wednesday having a slight effect on propagation crossing the northern polar region.

160 and 80 meter propagation from North America to VK/ZL and the South Pacific is likely to be normal through at least Wednesday . 160 and 80 meter long distance propagation in the northern hemisphere is always mildly to moderately degraded through September by E region blanketing of low angle F2 propagation until at least several hours after sunset.



40 meter short path propagation from North America to the Middle East and south Asia after 0030Z is likely to be normal through at least Wednesday. Short path propagation between North America and east Asia after about 0930Z is likely to be normal through at least Wednesday.


30 meter propagation crossing the auroral ovals and polar regions is likely to be normal through at least Wednesday. Daytime 30 meter long distance propagation is always mildly to moderately degraded within several hours of local noon by E-region blanketing of low angle F2 propagation.

20 meter propagation crossing the auroral ovals and polar regions is likely to be normal through at least Wednesday. 20 meter propagation beyond 2200 km in the northern hemisphere is likely to be mildly degraded through mid-September within several hours of local noon at more northerly mid latitudes, moderately degraded through late September at mid- latitudes , more severely degraded through October at more southerly mid-latitudes and severely degraded at low latitudes through at least October by E-region blanketing of low angle F2 propagation.


17 and 15 meter propagation crossing the auroral ovals and polar regions is likely to be normal through at least Wednesday. 17 and 15 meter long path propagation from North America to southeast and east Asia from about 1100Z to 1400Z is likely to be normal through at least Wednesday.



12 and 10 meter propagation is likely to be normal through at least Wednesday. 12 and 10 meter long path propagation from North America to southeast and east Asia from about 1100Z to 1400Z is likely to be normal through at least Wednesday.



Thermally driven high velocity seasonal thermospheric winds at F2 region altitude blow from the high temperature dayside hemisphere to the lower temperature nightside hemisphere reducing the volume of neutral atomic oxygen available to be ionized in the F2 region during daytime hours, lowering the MUF for F2 propagation crossing high latitudes to mostly less than 28 MHz and degrading the duration and reliability of 10 meter DX propagation crossing high latitudes through about mid-September.



Brief geographically focused 6 meter F2 propagation enhanced by TEP over Africa from the southern tier of US states to the Indian Ocean, equatorial and southern Africa (e.g., 3B8. 3B9, 7Q, D2, FR, V5, ZD7 and ZS) is extremely unlikely from about 1400-1800Z. There is a slight chance of F2 trans-equatorial propagation (TEP) from the southern tier of U.S. states to South America from about 2000-0200Z. Above-the-MUF oblique-TEP F2 propagation from the southern tier of US states to the south Pacific (e.g., 3D2, 5W, E5, FK, FO, VK4, VP6 and ZL) is extremely unlikely from about 1900-0300Z. It is extremely unlikely that more northerly U.S. stations may couple into TEP and oblique-TEP via geographically focused brief intervals of sporadic-E propagation. There is a chance of TEP propagation from about 2000-0200Z during the initial phase of strong to severe geomagnetic storms then degrading several hours after initial enhancement.

Sustained southward orientation (-Bz) of the north-south component of the interplanetary magnetic field (IMF) plays a crucial but unpredictable role in triggering all geomagnetic storms. Brief minor to moderate geomagnetic

storms may be gradually triggered when the IMF is sustained in a southward orientation (-Bz) with IMF field strength of about 5 nanoteslas or more for at least a few hours coincident with the influence of a geoeffective coronal hole high speed stream or CME. More frequent, longer duration, minor to severe geomagnetic storms may be triggered suddenly and unpredictably when the IMF is sustained in a southward orientation (-Bz) with IMF field strength of about 5 nanoteslas or more for a period of several hours or more coincident with the influence of a geoeffective CME and solar wind speed of about 500 km/second or more.



Mid-latitude northern hemisphere sunrise is 52 minutes later and sunset is 57 minutes earlier than it was on June 20th . Sunrise is about two hours earlier and sunset is about two hours later at the altitude of the refracting F2 region. Sunrise is about one hour earlier, and sunset is about one hour later at the altitude of the daytime absorbing D region.

[4L5A]

Some of the best summer solar maximum propagation of Solar Cycle 25 is likely to continue through at least Sunday.



Propagation crossing all latitudes is likely to be normal through at least Sunday.



40 meter DX propagation is likely from early evening until after sunrise.

30 meter DX propagation is likely from late afternoon until a few hours after sunrise.

20, 17 and 15 meter DX propagation is likely 24 hours per day.

12 meter DX propagation is likely from early morning until late night hours,

10 meter DX propagation is likely from mid-morning through early night hours.

This forecast derived from today 's NOAA/SWPC web pages and 15 other online sources (the URLs at the end of this forecast) is published five days a week (M-F) in The Daily DX .

All days and times in this forecast are in UTC (Zulu) time.



Global 6 meter F2 propagation may begin by late October if solar flux values continue to persist well above 200. 6 meter Trans-Equatorial F2 Propagation (TEP) is likely to occur regularly from the southern tier of US states from September through November. More northerly locations need an unlikely additional sporadic-E or F2 hop. 6 meter sporadic-E propagation beyond 2200 km is extremely unlikely until December.



The 2300Z Penticton 10.7 cm observed solar flux index was 203 and is likely to remain about the same through Sunday.


SILSO’s latest Estimated International Sunspot Number was 141 and is likely to remain about the same through Sunday.


The visible solar disk has two growing large solar active regions, one stable large solar active region, two growing medium solar active regions and two growing small solar active regions containing 44 sunspots with a total sunspot area of 1530 micro solar hemispheres (about nine times the surface area of the Earth).

Solar wind speed is likely to be 400 km/second or less through at least Sunday.



Mostly quiet geomagnetic conditions are likely through at least Sunday.

M-class solar flares are likely to cause a few minutes of minor to moderate radio blackouts of propagation paths crossing the sunlit side of the Earth through Sunday. There is a slight chance that X-class solar flares may cause about an hour of widespread blackouts of propagation paths crossing the sunlit side of the Earth through Sunday.

There is a slight chance of S1-class solar energetic particle radiation storms through Sunday having a slight effect on trans-polar propagation

160 and 80 meter propagation from North America to VK/ZL and the South Pacific is likely to be normal through at least Sunday . 160 and 80 meter long distance propagation in the northern hemisphere is always mildly to moderately degraded through September by E region blanketing of low angle F2 propagation until at least several hours after sunset.



40 meter short path propagation from North America to the Middle East and south Asia after 0030Z is likely to be normal through at least Sunday. Short path propagation between North America and east Asia after about 0930Z is likely to be normal through Sunday.


30 meter propagation crossing the auroral ovals and polar regions is likely to be normal through at least Sunday. Daytime 30 meter long distance propagation is always mildly to moderately degraded within several hours of local noon by E-region blanketing of low angle F2 propagation.

20 meter propagation crossing the auroral ovals and polar regions is likely to be normal through at least Sunday. 20 meter propagation beyond 2200 km in the northern hemisphere is likely to be mildly degraded through mid-September within several hours of local noon at more northerly mid latitudes, moderately degraded through late September at mid- latitudes and more severely degraded through October at more southerly mid-latitudes by E-region blanketing of low angle F2 propagation.


17 and 15 meter propagation crossing the auroral ovals and polar regions is likely to be normal through at least Sunday. 17 and 15 meter long path propagation from North America to southeast and east Asia from about 1100Z to 1400Z is likely to be normal through at least Sunday.



12 and 10 meter propagation is likely to be normal through at least Sunday. 12 and 10 meter long path propagation from North America to southeast and east Asia from about 1100Z to 1400Z is likely to be normal through at least Sunday.



Thermally driven high velocity seasonal thermospheric winds at F2 region altitude blow from the high temperature dayside hemisphere to the lower temperature nightside hemisphere reducing the volume of neutral atomic oxygen available to be ionized in the F2 region during daytime hours, lowering the MUF for F2 propagation crossing high latitudes to mostly less than 28 MHz and degrading the duration and reliability of 10 meter DX propagation crossing high latitudes through about mid-September.



Brief geographically focused 6 meter F2 propagation enhanced by TEP over Africa from the southern tier of US states to the Indian Ocean, equatorial and southern Africa (e.g., 3B8. 3B9, 7Q, D2, FR, V5, ZD7 and ZS) is extremely unlikely from about 1400-1800Z. There is a slight chance of F2 trans-equatorial propagation (TEP) from the southern tier of U.S. states to South America from about 2000-0200Z. Above-the-MUF oblique-TEP F2 propagation from the southern tier of US states to the south Pacific (e.g., 3D2, 5W, E5, FK, FO, VK4, VP6 and ZL) is extremely unlikely from about 1900-0300Z. It is extremely unlikely that more northerly U.S. stations may couple into TEP and oblique-TEP via geographically focused brief intervals of sporadic-E propagation. There is a chance of TEP propagation from about 2000-0200Z during the initial phase of strong to severe geomagnetic storms then degrading several hours after initial enhancement.
Sustained southward orientation (-Bz) of the north-south component of the interplanetary magnetic field (IMF) plays a crucial but unpredictable role in triggering all geomagnetic storms. Brief minor to moderate geomagnetic

storms may be gradually triggered when the IMF is sustained in a southward orientation (-Bz) with IMF field strength of about 5 nanoteslas or more for at least a few hours coincident with the influence of a geoeffective coronal hole high speed stream or CME. More frequent, longer duration, minor to severe geomagnetic storms may be triggered suddenly and unpredictably when the IMF is sustained in a southward orientation (-Bz) with IMF field strength of about 5 nanoteslas or more for a period of several hours or more coincident with the influence of a geoeffective CME and solar wind speed of about 500 km/second or more.



Mid-latitude northern hemisphere sunrise is 50 minutes later and sunset is 54 minutes earlier than it was on June 20th . Sunrise is about two hours earlier and sunset is about two hours later at the altitude of the refracting F2 region. Sunrise is about one hour earlier, and sunset is about one hour later at the altitude of the daytime absorbing D region.

[4L5A]

Some of the best summer solar maximum propagation of Solar Cycle 25 is likely to continue through at least Saturday, except for ongoing mild degradation of high latitude propagation paths likely to end by midday Thursday.



Propagation crossing low latitudes is likely to be normal through Saturday.

Propagation crossing mid latitudes is likely to be normal through Saturday.

Propagation crossing high latitudes is likely to be normal through Saturday except for ongoing mild degradation likely to end by midday Thursday.



40 meter DX propagation is likely from early evening until after sunrise.

30 meter DX propagation is likely from late afternoon until a few hours after sunrise.

20, 17 and 15 meter DX propagation is likely 24 hours per day.

12 meter DX propagation is likely from early morning until late night hours,

10 meter DX propagation is likely from mid-morning through early night hours.

This forecast derived from today 's NOAA/SWPC web pages and 15 other online sources (the URLs at the end of this forecast) is published five days a week (M-F) in The Daily DX .

All days and times in this forecast are in UTC (Zulu) time.



Global 6 meter F2 propagation may begin by late October if solar flux values continue to persist well above 200. 6 meter Trans-Equatorial F2 Propagation (TEP) is likely to occur regularly from the southern tier of US states from September through November. More northerly locations need an unlikely additional sporadic-E or F2 hop. 6 meter sporadic-E propagation beyond 2200 km is extremely unlikely until December.



The 2300Z Penticton 10.7 cm observed solar flux index was 208 and is likely to remain about the same through Saturday.


SILSO’s latest Estimated International Sunspot Number was 180 and is likely to remain about the same through Saturday.

The visible solar disk has one stable large solar active region, one decaying large solar active region, two stable medium solar active regions, two decaying medium solar active regions, one growing small solar active region, one stable small active region, one stable very small solar active region and one decaying very small solar active region containing 53 sunspots with a total sunspot area of 1520 micro solar hemispheres (about nine times the surface area of the Earth).

Solar wind speed is likely to be 400 km/second or less through at least Saturday.



Mostly quiet geomagnetic conditions are likely through Saturday except for an ongoing brief period of unsettled to active geomagnetic conditions likely to end by midday Thursday.

M-class solar flares are likely to cause a few minutes of minor to moderate radio blackouts of propagation paths crossing the sunlit side of the Earth through Saturday. There is a slight chance that X-class solar flares may cause about an hour of widespread blackouts of propagation paths crossing the sunlit side of the Earth through Saturday.

There is a slight chance of S1-class solar energetic particle radiation storms through Saturday having a slight effect on trans-polar propagation

160 and 80 meter propagation from North America to VK/ZL and the South Pacific is likely to be normal through Saturday . 160 and 80 meter long distance propagation in the northern hemisphere is always mildly to moderately degraded through September by E region blanketing of low angle F2 propagation until at least several hours after sunset.



40 meter short path propagation from North America to the Middle East and south Asia after 0030Z is likely to be normal through Saturday. Short path propagation between North America and east Asia after about 0930Z is likely to be normal through Saturday.


30 meter propagation crossing the auroral ovals and polar regions is likely to be normal through Saturday except for ongoing mild degradation likely to end by midday Thursday. Daytime 30 meter long distance propagation is always mildly to moderately degraded within several hours of local noon by E-region blanketing of low angle F2 propagation.

20 meter propagation crossing the auroral ovals and polar regions is likely to be normal through Saturday except for ongoing mild degradation likely to end by midday Thursday. 20 meter propagation beyond 2200 km in the northern hemisphere is likely to be mildly degraded through mid-September within several hours of local noon at more northerly mid latitudes, moderately degraded through late September at mid- latitudes and more severely degraded through October at more southerly mid-latitudes by E-region blanketing of low angle F2 propagation.


17 and 15 meter propagation crossing the auroral ovals and polar regions is likely to be normal through Saturday except for ongoing mild degradation likely to end by midday Thursday. 17 and 15 meter long path propagation from North America to southeast and east Asia from about 1100Z to 1400Z is likely to be normal through Saturday.



12 and 10 meter propagation is likely to be normal through Saturday except for ongoing mild degradation likely to end by midday Thursday. 12 and 10 meter long path propagation from North America to southeast and east Asia from about 1100Z to 1400Z is likely to be normal through Saturday.



Thermally driven high velocity seasonal thermospheric winds at F2 region altitude blow from the high temperature dayside hemisphere to the lower temperature nightside hemisphere reducing the volume of neutral atomic oxygen available to be ionized in the F2 region during daytime hours, lowering the MUF for F2 propagation crossing high latitudes to mostly less than 28 MHz and degrading the duration and reliability of 10 meter DX propagation crossing high latitudes through about mid-September.



Brief geographically focused 6 meter F2 propagation enhanced by TEP over Africa from the southern tier of US states to the Indian Ocean, equatorial and southern Africa (e.g., 3B8. 3B9, 7Q, D2, FR, V5, ZD7 and ZS) is extremely unlikely from about 1400-1800Z. There is a slight chance of F2 trans-equatorial propagation (TEP) from the southern tier of U.S. states to South America from about 2000-0200Z. Above-the-MUF oblique-TEP F2 propagation from the southern tier of US states to the south Pacific (e.g., 3D2, 5W, E5, FK, FO, VK4, VP6 and ZL) is extremely unlikely from about 1900-0300Z. It is extremely unlikely that more northerly U.S. stations may couple into TEP and oblique-TEP via geographically focused brief intervals of sporadic-E propagation. There is a chance of TEP propagation from about 2000-0200Z during the initial phase of strong to severe geomagnetic storms then degrading several hours after initial enhancement.

Sustained southward orientation (-Bz) of the north-south component of the interplanetary magnetic field (IMF) plays a crucial but unpredictable role in triggering all geomagnetic storms. Brief minor to moderate geomagnetic

storms may be gradually triggered when the IMF is sustained in a southward orientation (-Bz) with IMF field strength of about 5 nanoteslas or more for at least a few hours coincident with the influence of a geoeffective coronal hole high speed stream or CME. More frequent, longer duration, minor to severe geomagnetic storms may be triggered suddenly and unpredictably when the IMF is sustained in a southward orientation (-Bz) with IMF field strength of about 5 nanoteslas or more for a period of several hours or more coincident with the influence of a geoeffective CME and solar wind speed of about 500 km/second or more.



Mid-latitude northern hemisphere sunrise is 48 minutes later and sunset is 51 minutes earlier than it was on June 20th . Sunrise is about two hours earlier and sunset is about two hours later at the altitude of the refracting F2 region. Sunrise is about one hour earlier, and sunset is about one hour later at the altitude of the daytime absorbing D region.

[4L5A]

Propagation crossing low latitudes is likely to be normal through Friday.

Propagation crossing mid latitudes is likely to be normal through Friday except for ongoing mild degradation through midday Wednesday.

Propagation crossing high latitudes is likely to be normal through Friday except for ongoing mild to moderate degradation through midday Wednesday.



40 and 30 meter DX propagation is likely from early evening until after sunrise.

20, 17 and 15 meter DX propagation is likely 24 hours per day.

12 meter DX propagation is likely from early morning until late night hours,

10 meter DX propagation is likely from mid-morning through early night hours.

This forecast derived from today 's NOAA/SWPC web pages and 15 other online sources (the URLs at the end of this forecast) is published five days a week (M-F) in The Daily DX .

All days and times in this forecast are in UTC (Zulu) time.



Global 6 meter F2 propagation may begin by late October if solar flux values continue to persist well above 200. 6 meter Trans-Equatorial F2 Propagation (TEP) is likely to occur regularly from the southern tier of US states from September through November. More northerly locations need an additional sporadic-E or F2 hop. 6 meter sporadic-E propagation beyond 2200 km is extremely unlikely until December.



The 2300Z Penticton 10.7 cm observed solar flux index was 214 and is likely to remain about the same through Friday.

SILSO’s latest Estimated International Sunspot Number was 183 and is likely to remain about the same through Friday.

The visible solar disk has two stable large solar active regions, one decaying large solar active region, one growing medium solar active region, one stable medium active region, one decaying medium solar active region and four stable small active regions containing 70 sunspots with a total sunspot area of 1950 micro solar hemispheres (about 12 times the surface area of the Earth).

Solar wind speed is likely to be 400 km/second or less through at least Friday.



Mostly quiet geomagnetic conditions are likely through Friday except for ongoing brief periods of unsettled to active geomagnetic conditions through midday Wednesday.


M-class solar flares are likely to cause a few minutes of minor to moderate radio blackouts of propagation paths crossing the sunlit side of the Earth through Friday. There is a slight chance that X-class solar flares may cause about an hour of widespread blackouts of propagation paths crossing the sunlit side of the Earth through Friday.

There is a slight chance of S1-class solar energetic particle radiation storms through Friday having a slight effect on trans-polar propagation

160 and 80 meter propagation from North America to VK/ZL and the South Pacific is likely to be normal through Friday . 160 and 80 meter long distance propagation in the northern hemisphere is always mildly to moderately degraded through September by E region blanketing of low angle F2 propagation until at least several hours after sunset.



40 meter short path propagation from North America to the Middle East and south Asia after 0030Z is likely to be normal through Friday. Short path propagation between North America and east Asia after about 0930Z is likely to be mostly normal on Wednesday and normal on Thursday and Friday.


30 meter propagation crossing the auroral ovals and polar regions is likely to be normal through Friday except for ongoing brief periods of mild to moderate degradation through midday Wednesday. Daytime 30 meter long distance propagation is always mildly to moderately degraded within several hours of local noon by E-region blanketing of low angle F2 propagation.

20 meter propagation crossing the auroral ovals and polar regions is likely to be normal through Friday except for ongoing brief periods of mild to moderate degradation through midday Wednesday. 20 meter propagation beyond 2200 km in the northern hemisphere through September is likely to be moderately degraded within several hours of local noon especially at more southerly latitudes by E-region blanketing of low angle F2 propagation.


17 and 15 meter propagation crossing the auroral ovals and polar regions is likely to be normal through Friday except for ongoing brief periods of mild to moderate degradation through midday Wednesday, 17 and 15 meter long path propagation from North America to southeast and east Asia from about 1100Z to 1400Z is likely to be normal through Friday.



12 and 10 meter propagation is likely to be normal through Friday except for ongoing brief periods of mild to moderate degradation through midday Wednesday. 12 and 10 meter long path propagation from North America to southeast and east Asia from about 1100Z to 1400Z is likely to be normal through Friday.



Thermally driven high velocity seasonal thermospheric winds at F2 region altitude blow from the high temperature dayside hemisphere to the lower temperature nightside hemisphere reducing the volume of neutral atomic oxygen available to be ionized in the F2 region during daytime hours, lowering the MUF for F2 propagation crossing high latitudes to mostly less than 28 MHz and degrading the duration and reliability of 10 meter DX propagation crossing high latitudes through about mid-September.



Brief geographically focused 6 meter F2 propagation enhanced by TEP over Africa from the southern tier of US states to the Indian Ocean, equatorial and southern Africa (e.g., 3B8. 3B9, 7Q, D2, FR, V5, ZD7 and ZS) is extremely unlikely from about 1400-1800Z. There is a slight chance of F2 trans-equatorial propagation (TEP) from the southern tier of U.S. states to South America from about 2000-0200Z. Above-the-MUF oblique-TEP F2 propagation from the southern tier of US states to the south Pacific (e.g., 3D2, 5W, E5, FK, FO, VK4, VP6 and ZL) is extremely unlikely from about 1900-0300Z. It is extremely unlikely that more northerly U.S. stations may couple into TEP and oblique-TEP via geographically focused brief intervals of sporadic-E propagation. There is a chance of TEP propagation from about 2000-0200Z during the initial phase of strong to severe geomagnetic storms then degrading several hours after initial enhancement.

Sustained southward orientation (-Bz) of the north-south component of the interplanetary magnetic field (IMF) plays a crucial but unpredictable role in triggering all geomagnetic storms. Brief minor to moderate geomagnetic

storms may be gradually triggered when the IMF is sustained in a southward orientation (-Bz) with IMF field strength of about 5 nanoteslas or more for at least a few hours coincident with the influence of a geoeffective coronal hole high speed stream or CME. More frequent, longer duration, minor to severe geomagnetic storms may be triggered suddenly and unpredictably when the IMF is sustained in a southward orientation (-Bz) with IMF field strength of about 5 nanoteslas or more for a period of several hours or more coincident with the influence of a geoeffective CME and solar wind speed of about 500 km/second or more.



Mid-latitude northern hemisphere sunrise is 48 minutes later and sunset is 51 minutes earlier than it was on June 20th . Sunrise is about two hours earlier and sunset is about two hours later at the altitude of the refracting F2 region. Sunrise is about one hour earlier, and sunset is about one hour later at the altitude of the daytime absorbing D region.