The Tuesday May 21st W3LPL propagation 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.
The 2300Z Penticton 10.7 cm observed solar flux index was 194 and is likely to remain about the same through Wednesday.
[ http://www.spaceweather.gc.ca/foreca...ux/sx-4-en.php | http://www.spaceweather.gc.ca/foreca...ux/sx-4-en.php ]
SILSO’s latest Estimated International Sunspot Number was 143 and is likely to remain about the same through Wednesday.
[ https://www.sidc.be/SILSO/DATA/EISN/EISNcurrent.png | www.sidc.be/SILSO/DATA/EISN/EISNcurrent.png ]
The visible solar disk has one very large, four large and one very small active region containing 64 sunspots with a total sunspot area of 840 micro solar hemispheres (about five times the surface area of the Earth).
[ https://www.solarham.net/regions.htm | www.solarham.net/regions.htm ]
Solar wind speed is likely to be near background levels of about 400 km/second or less through Wednesday.
Geomagnetic activity is likely to be mostly unsettled on Tuesday improving to mostly quiet on Wednesday.
[ https://www.swpc.noaa.gov/phenomena/...mass-ejections | http://www.swpc.noaa.gov/phenomena/c...mass-ejections ]
[ https://www.swpc.noaa.gov/phenomena/coronal-holes | www.swpc.noaa.gov/phenomena/coronal-holes ]
Isolated M-class solar flares are expected to cause minor to moderate radio blackouts through Wednesday, mildly degrading propagation crossing near the sub-solar point on the sunlit side of the Earth for tens of minutes during each event.
[ https://www.swpc.noaa.gov/phenomena/...adio-blackouts | http://www.swpc.noaa.gov/phenomena/s...adio-blackouts ]
There is a slight chance that weak solar radiation storms may mildly degrade HF propagation crossing polar regions through Wednesday.
[ https://www.swpc.noaa.gov/phenomena/...adiation-storm | http://www.swpc.noaa.gov/phenomena/s...adiation-storm ]
160 and 80 meter propagation from North America to VK/ZL and the South Pacific is likely to be normal through Wednesday.
40 meter short path propagation from North America to the Middle East and south Asia is likely to be normal after 0015Z Wednesday. Short path propagation between North America and east Asia after about 0930Z is likely to be mostly normal on Tuesday and normal on Wednesday .
30 meter propagation crossing the auroral ovals and polar regions is likely to be mostly normal on Tuesday improving to normal on Wednesday . 30 meter propagation is always mildly to moderately degraded within several hours of local noon by E-region blanketing of long distance low angle F2 propagation.
20 meter propagation crossing the auroral ovals and polar regions is likely to be mostly normal on Tuesday improving to normal on Wednesday.
17 and 15 meter propagation crossing the auroral ovals and polar regions is likely to be mostly normal on Tuesday improving to normal on Wednesday . 17 and 15 meter long path propagation from North America to southeast and east Asia from about 1200Z to 1400Z is likely to be mostly normal on Tuesday improving to normal on Wednesday.
12 and 10 meter propagation is likely to be mostly normal on Tuesday improving to normal on Wednesday . 12 and 10 meter long path propagation from North America to southeast and east Asia from about 1200Z to 1400Z is likely to be mostly normal on Tuesday improving to normal on Wednesday. Thermally driven high velocity winds in the summer F2 region blowing from the dayside hemisphere to the nightside hemisphere reduce the volume of neutral oxygen available for daytime ionization degrading daytime 12 and 10 meter long distance F2 propagation in the northern hemisphere from late spring through late summer.
There is a very slight chance of brief, isolated, geographically focused 6 meter above-the-MUF trans-Atlantic F2 propagation from about 1400-1600Z between mid-latitude U.S states and western Europe, this propagation may be skewed towards the equator. There is a very slight chance of 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) from about 1400-1800Z. There is a chance of F2 trans-equatorial propagation (TEP) from the southern tier of U.S. states to South America from about 2000-0200Z. There is a very slight chance of above-the-MUF F2 propagation enhanced by oblique-TEP from the southern tier of US states to the south Pacific (e.g., 3D2, 5W, E5, FK, FO, VK4, VK9, ZL and ZL7) from about 2100-0300Z. There is a chance that more northerly U.S. stations may couple into TEP and oblique-TEP via geographically focused brief intervals of sporadic-E propagation. TEP may be significantly enhanced from about 2000-0200Z during the initial phase of strong to severe geomagnetic storms then degrading several hours after initial enhancement. See K6MIO’s excellent article on 6 meter TEP, oblique-TEP, TEP-related and mid-latitude sporadic-E linking to TEP beginning on page 9 at: [ http://www.oh3ac.fi/QEX-2016-11.pdf | http://www.oh3ac.fi/QEX-2016-11.pdf ]
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 82 minutes earlier and sunset is 61 minutes later than on March 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 absorbing D region.
EarthSky’s Sun News is published daily at
[ https://earthsky.org/sun/sun-news-ac...aurora-updates | earthsky.org/sun/sun-news-activity-solar-flare-cme-aurora-updates ]
Dr. Tamitha Skov’s latest space weather news is posted at
[ https://twitter.com/TamithaSkov | twitter.com/TamithaSkov ]
Northwest Research Associate’s Table of Space Weather Indices is updated 40 minutes after every hour at
[ https://spawx.nwra.com/spawx/env_latest.html | https://spawx.nwra.com/spawx/env_latest.html ]
SILSO’s Estimated International Sunspot Number is updated frequently at [ http://www.sidc.be/silso/DATA/EISN/EISNcurrent.png | www.sidc.be/silso/DATA/EISN/EISNcurrent.png ]
The Penticton 10.7 cm solar flux index is updated every day at 1700, 2000 and 2300Z at
[ http://www.spaceweather.gc.ca/foreca...-5-flux-en.php | http://www.spaceweather.gc.ca/foreca...-5-flux-en.php ]
SWPC’s Estimated Planetary Kp Index is updated every three hours at [ https://services.swpc.noaa.go-index.png/ | https://services.swpc.noaa.go-index.png ]
UK Met Office’s EUHFORIA solar wind report and forecast is updated daily at [ https://swe.ssa.esa.int/DOCS/portal_...#1708014964422 | https://swe.ssa.esa.int/DOCS/portal_...#1708014964422 ]
UK Met Office’s Solar Flare Forecast is updated daily at
[ https://swe.ssa.esa.int/web/guest/ukmo-S109c-federated | https://swe.ssa.esa.int/web/guest/ukmo-S109c-federated ]
UK Met Office’s Solar Wind Forecast and CME Arrival Prediction is updated regularly at
[ https://swe.ssa.esa.int/metoffice-enlil-e-federated | https://swe.ssa.esa.int/metoffice-enlil-e-federated ]
N0NBH’s Current HF Band Conditions Report is updated regularly at
[ http://www.hamqsl.com/solar.html | www.hamqsl.com/solar.html ]
KC2G’s Near-Real-Time Maps and Data about HF propagation are generated every 15 minutes, from near real time data usually only 5 to 20 minutes old at
[ https://prop.kc2g.com/ | https://prop.kc2g.com ]
SWPC’s Real Time 24 hour Geomagnetic Data including Bz orientation, IMF field strength , solar wind speed and near real time 30 minute forecasts are updated frequently at
[ http://www.swpc.noaa.gov/products/ge...-activity-plot | http://www.swpc.noaa.gov/products/ge...-activity-plot ]
SIDC’s Daily Bulletin on Solar and Geomagnetic Activity is updated daily at 1230Z at [ http://www.sidc.be/spaceweatherservi...uct/meu/latest | http://www.sidc.be/spaceweatherservi...uct/meu/latest ]
GFZ-Potsdam’s three-day GFZ Planetary K Index Forecast is updated every three hours at
[ https://spaceweather.gfz-potsdam.de/...ecast-kp-index | https://spaceweather.gfz-potsdam.de/...ecast-kp-index ]
SWPC’s Solar Activity Forecast and Discussion is updated daily at 0030Z and 1230Z at
[ http://www.swpc.noaa.gov/products/forecast-discussion | www.swpc.noaa.gov/products/forecast-discussion ]
Perhaps the most useful HF propagation pages for DXers can be found at
[ http://dx.qsl.net/propagation | http://dx.qsl.net/propagation ] and [ http://www.solarham.com/ | www.solarham.com
All days and times in this forecast are in UTC (Zulu) time.
The 2300Z Penticton 10.7 cm observed solar flux index was 194 and is likely to remain about the same through Wednesday.
[ http://www.spaceweather.gc.ca/foreca...ux/sx-4-en.php | http://www.spaceweather.gc.ca/foreca...ux/sx-4-en.php ]
SILSO’s latest Estimated International Sunspot Number was 143 and is likely to remain about the same through Wednesday.
[ https://www.sidc.be/SILSO/DATA/EISN/EISNcurrent.png | www.sidc.be/SILSO/DATA/EISN/EISNcurrent.png ]
The visible solar disk has one very large, four large and one very small active region containing 64 sunspots with a total sunspot area of 840 micro solar hemispheres (about five times the surface area of the Earth).
[ https://www.solarham.net/regions.htm | www.solarham.net/regions.htm ]
Solar wind speed is likely to be near background levels of about 400 km/second or less through Wednesday.
Geomagnetic activity is likely to be mostly unsettled on Tuesday improving to mostly quiet on Wednesday.
[ https://www.swpc.noaa.gov/phenomena/...mass-ejections | http://www.swpc.noaa.gov/phenomena/c...mass-ejections ]
[ https://www.swpc.noaa.gov/phenomena/coronal-holes | www.swpc.noaa.gov/phenomena/coronal-holes ]
Isolated M-class solar flares are expected to cause minor to moderate radio blackouts through Wednesday, mildly degrading propagation crossing near the sub-solar point on the sunlit side of the Earth for tens of minutes during each event.
[ https://www.swpc.noaa.gov/phenomena/...adio-blackouts | http://www.swpc.noaa.gov/phenomena/s...adio-blackouts ]
There is a slight chance that weak solar radiation storms may mildly degrade HF propagation crossing polar regions through Wednesday.
[ https://www.swpc.noaa.gov/phenomena/...adiation-storm | http://www.swpc.noaa.gov/phenomena/s...adiation-storm ]
160 and 80 meter propagation from North America to VK/ZL and the South Pacific is likely to be normal through Wednesday.
40 meter short path propagation from North America to the Middle East and south Asia is likely to be normal after 0015Z Wednesday. Short path propagation between North America and east Asia after about 0930Z is likely to be mostly normal on Tuesday and normal on Wednesday .
30 meter propagation crossing the auroral ovals and polar regions is likely to be mostly normal on Tuesday improving to normal on Wednesday . 30 meter propagation is always mildly to moderately degraded within several hours of local noon by E-region blanketing of long distance low angle F2 propagation.
20 meter propagation crossing the auroral ovals and polar regions is likely to be mostly normal on Tuesday improving to normal on Wednesday.
17 and 15 meter propagation crossing the auroral ovals and polar regions is likely to be mostly normal on Tuesday improving to normal on Wednesday . 17 and 15 meter long path propagation from North America to southeast and east Asia from about 1200Z to 1400Z is likely to be mostly normal on Tuesday improving to normal on Wednesday.
12 and 10 meter propagation is likely to be mostly normal on Tuesday improving to normal on Wednesday . 12 and 10 meter long path propagation from North America to southeast and east Asia from about 1200Z to 1400Z is likely to be mostly normal on Tuesday improving to normal on Wednesday. Thermally driven high velocity winds in the summer F2 region blowing from the dayside hemisphere to the nightside hemisphere reduce the volume of neutral oxygen available for daytime ionization degrading daytime 12 and 10 meter long distance F2 propagation in the northern hemisphere from late spring through late summer.
There is a very slight chance of brief, isolated, geographically focused 6 meter above-the-MUF trans-Atlantic F2 propagation from about 1400-1600Z between mid-latitude U.S states and western Europe, this propagation may be skewed towards the equator. There is a very slight chance of 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) from about 1400-1800Z. There is a chance of F2 trans-equatorial propagation (TEP) from the southern tier of U.S. states to South America from about 2000-0200Z. There is a very slight chance of above-the-MUF F2 propagation enhanced by oblique-TEP from the southern tier of US states to the south Pacific (e.g., 3D2, 5W, E5, FK, FO, VK4, VK9, ZL and ZL7) from about 2100-0300Z. There is a chance that more northerly U.S. stations may couple into TEP and oblique-TEP via geographically focused brief intervals of sporadic-E propagation. TEP may be significantly enhanced from about 2000-0200Z during the initial phase of strong to severe geomagnetic storms then degrading several hours after initial enhancement. See K6MIO’s excellent article on 6 meter TEP, oblique-TEP, TEP-related and mid-latitude sporadic-E linking to TEP beginning on page 9 at: [ http://www.oh3ac.fi/QEX-2016-11.pdf | http://www.oh3ac.fi/QEX-2016-11.pdf ]
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 82 minutes earlier and sunset is 61 minutes later than on March 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 absorbing D region.
EarthSky’s Sun News is published daily at
[ https://earthsky.org/sun/sun-news-ac...aurora-updates | earthsky.org/sun/sun-news-activity-solar-flare-cme-aurora-updates ]
Dr. Tamitha Skov’s latest space weather news is posted at
[ https://twitter.com/TamithaSkov | twitter.com/TamithaSkov ]
Northwest Research Associate’s Table of Space Weather Indices is updated 40 minutes after every hour at
[ https://spawx.nwra.com/spawx/env_latest.html | https://spawx.nwra.com/spawx/env_latest.html ]
SILSO’s Estimated International Sunspot Number is updated frequently at [ http://www.sidc.be/silso/DATA/EISN/EISNcurrent.png | www.sidc.be/silso/DATA/EISN/EISNcurrent.png ]
The Penticton 10.7 cm solar flux index is updated every day at 1700, 2000 and 2300Z at
[ http://www.spaceweather.gc.ca/foreca...-5-flux-en.php | http://www.spaceweather.gc.ca/foreca...-5-flux-en.php ]
SWPC’s Estimated Planetary Kp Index is updated every three hours at [ https://services.swpc.noaa.go-index.png/ | https://services.swpc.noaa.go-index.png ]
UK Met Office’s EUHFORIA solar wind report and forecast is updated daily at [ https://swe.ssa.esa.int/DOCS/portal_...#1708014964422 | https://swe.ssa.esa.int/DOCS/portal_...#1708014964422 ]
UK Met Office’s Solar Flare Forecast is updated daily at
[ https://swe.ssa.esa.int/web/guest/ukmo-S109c-federated | https://swe.ssa.esa.int/web/guest/ukmo-S109c-federated ]
UK Met Office’s Solar Wind Forecast and CME Arrival Prediction is updated regularly at
[ https://swe.ssa.esa.int/metoffice-enlil-e-federated | https://swe.ssa.esa.int/metoffice-enlil-e-federated ]
N0NBH’s Current HF Band Conditions Report is updated regularly at
[ http://www.hamqsl.com/solar.html | www.hamqsl.com/solar.html ]
KC2G’s Near-Real-Time Maps and Data about HF propagation are generated every 15 minutes, from near real time data usually only 5 to 20 minutes old at
[ https://prop.kc2g.com/ | https://prop.kc2g.com ]
SWPC’s Real Time 24 hour Geomagnetic Data including Bz orientation, IMF field strength , solar wind speed and near real time 30 minute forecasts are updated frequently at
[ http://www.swpc.noaa.gov/products/ge...-activity-plot | http://www.swpc.noaa.gov/products/ge...-activity-plot ]
SIDC’s Daily Bulletin on Solar and Geomagnetic Activity is updated daily at 1230Z at [ http://www.sidc.be/spaceweatherservi...uct/meu/latest | http://www.sidc.be/spaceweatherservi...uct/meu/latest ]
GFZ-Potsdam’s three-day GFZ Planetary K Index Forecast is updated every three hours at
[ https://spaceweather.gfz-potsdam.de/...ecast-kp-index | https://spaceweather.gfz-potsdam.de/...ecast-kp-index ]
SWPC’s Solar Activity Forecast and Discussion is updated daily at 0030Z and 1230Z at
[ http://www.swpc.noaa.gov/products/forecast-discussion | www.swpc.noaa.gov/products/forecast-discussion ]
Perhaps the most useful HF propagation pages for DXers can be found at
[ http://dx.qsl.net/propagation | http://dx.qsl.net/propagation ] and [ http://www.solarham.com/ | www.solarham.com
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