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    Geomagnetic storms and active geomagnetic conditions are about half as likely through mid-July compared to their more frequent occurrence during the equinox seasons.



    We are in the prime northern hemisphere 6 meter sporadic-E season through mid-July.



    The 2300Z Penticton 10.7 cm observed solar flux index was 166 and is likely to remain about the same through Saturday.

    SILSO’s latest Estimated International Sunspot Number was 149 and is likely to remain about the same through Saturday.

    The visible solar disk has two medium, five small and four very small active region containing 72 sunspots with a total sunspot area of 670 micro solar hemispheres (about four times the surface area of the Earth).

    Solar wind speed is likely to be near background levels less than 400 km/second through at least Saturday.



    Geomagnetic activity is likely to be mostly quiet through at least Saturday.

    M-class solar flares are likely to cause minor to moderate radio blackouts of propagation paths crossing the sunlit side of the Earth through at least Saturday.

    No S-class solar radiation storms are expected through at least Saturday.

    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 from June through September in the northern hemisphere is always mildly to moderately degraded 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 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 at least 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 F2 propagation.

    20 meter propagation crossing the auroral ovals and polar regions is likely to be normal through at least Saturday. Midday 20 meter long distance propagation from June through September in the northern hemisphere is always moderately degraded within several hours of local noon 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 Saturday. 17 and 15 meter long path propagation from North America to southeast and east Asia from about 1200Z to 1400Z is likely to be normal through at least Saturday .



    12 and 10 meter propagation is likely to be normal through at least Saturday.



    Thermally driven high velocity thermospheric winds at the altitude of the F2 region blow from the high temperature dayside hemisphere to the low temperature nightside hemisphere reducing the volume of neutral atomic oxygen available for ionizing the F2 region during daytime hours, lowering the MUF of 12 meter F2 propagation crossing the northern hemisphere through mid-September and lowering the MUF of 10 meter F2 propagation crossing the northern hemisphere through late-September.



    There is a slight chance of brief, isolated, geographically focused 6 meter trans-Atlantic sporadic-E propagation from about 1100-2200Z between mid-latitude U.S states and Europe, North Africa and the Middle East. 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 slight 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 oblique-TEP F2 propagation from the southern tier of US states to the south Pacific (e.g., 3D2, 5W, E5, FK, FO, VK4, VK9, VP6, ZL and ZL7) from about 1900-0300Z. 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.

    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 five minutes later and sunset is one minute later 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 absorbing D region.


    73 Al 4L5A

    Comment

    •  

      Geomagnetic storms and active geomagnetic conditions are about half as likely through mid-July compared to their more frequent occurrence during the equinox seasons.



      We are in the prime northern hemisphere 6 meter sporadic-E season through mid-July.



      The 2300Z Penticton 10.7 cm observed solar flux index was 172 and is likely to remain about the same through Sunday.

      SILSO’s latest Estimated International Sunspot Number was 170 and is likely to remain about the same through Sunday.

      The visible solar disk has four medium, one small and two very small active region containing 43 sunspots with a total sunspot area of 730 micro solar hemispheres (about four times the surface area of the Earth).

      Solar wind speed is likely to be near background levels less than 400 km/second through Sunday.



      Geomagnetic activity is likely to be mostly quiet through Sunday.


      M-class solar flares are likely to cause minor to moderate radio blackouts of propagation paths crossing the sunlit side of the Earth through Sunday.

      No S-class solar radiation storms are expected through Sunday.

      160 and 80 meter propagation from North America to VK/ZL and the South Pacific is likely to be normal through Sunday . 160 and 80 meter long distance propagation from June through September in the northern hemisphere is always mildly to moderately degraded 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 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 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 Sunday. Midday 20 meter long distance propagation in the northern hemisphere from June through September is always moderately degraded within several hours of local noon 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 Sunday. 17 and 15 meter long path propagation from North America to southeast and east Asia from about 1200Z to 1400Z is likely to be normal through Sunday .



      12 and 10 meter propagation is likely to be normal through Sunday.



      Thermally driven high velocity thermospheric winds at the altitude of the F2 region blow from the high temperature dayside hemisphere to the low temperature nightside hemisphere reducing the volume of neutral atomic oxygen available for ionizing the F2 region during daytime hours, lowering the MUF of 12 meter F2 propagation crossing the northern hemisphere through mid-September and lowering the MUF of 10 meter F2 propagation crossing the northern hemisphere through late-September.



      There is a slight chance of brief, isolated, geographically focused 6 meter trans-Atlantic sporadic-E propagation from about 1100-2200Z between mid-latitude U.S states and Europe, North Africa and the Middle East. 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 very slight 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 oblique-TEP F2 propagation from the southern tier of US states to the south Pacific (e.g., 3D2, 5W, E5, FK, FO, VK4, VK9, VP6, ZL and ZL7) from about 1900-0300Z. There is a very 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.

      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 six minutes later and sunset is one minute later 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 absorbing D region.


      73 Al 4L5A

      Comment

      •  

        Geomagnetic storms and active geomagnetic conditions are about half as likely through mid-July compared to their more frequent occurrence during the equinox seasons.



        Although we are in the prime northern hemisphere 6 meter sporadic-E season through mid-July, solar maximum effects are causing less frequent and shorter duration long distance sporadic-E propagation beyond 2200 km than in recent years.



        The 2300Z Penticton 10.7 cm observed solar flux index was 182 and is likely to remain about the same through Wednesday.

        SILSO’s latest Estimated International Sunspot Number was 99 and is likely to remain about the same through Wednesday.

        The visible solar disk has two medium, one small and five very small active region containing 29 sunspots with a total sunspot area of 650 micro solar hemispheres (about four times the surface area of the Earth).

        Solar wind speed is likely to be mildly elevated about 450 km/second through Tuesday, declining to less than 400 km/second by Wednesday



        Geomagnetic activity is likely to be mostly quiet to unsettled through Tuesday improving to quiet on Wednesday.


        M-class solar flares are likely to cause minor to moderate radio blackouts of propagation paths crossing the sunlit side of the Earth through Wednesday.

        No S-class solar radiation storms are expected through Wednesday.

        160 and 80 meter propagation from North America to VK/ZL and the South Pacific is likely to be normal through Wednesday . 160 and 80 meter long distance propagation from June through September in the northern hemisphere is always mildly to moderately degraded 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. Short path propagation between North America and east Asia after about 0930Z is likely to be mostly normal through Wednesday.


        30 meter propagation crossing the auroral ovals and polar regions is likely to be mostly normal through through 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 mostly normal through Wednesday. Midday 20 meter long distance propagation in the northern hemisphere from June through September is always moderately degraded within several hours of local noon 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 mostly normal through 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 through Wednesday .



        12 and 10 meter propagation is likely to be mostly normal through Wednesday.



        Thermally driven high velocity thermospheric winds at the altitude of the F2 region blow from the high temperature dayside hemisphere to the low temperature nightside hemisphere reducing the volume of neutral atomic oxygen available for ionizing the F2 region during daytime hours, lowering the MUF of 12 meter F2 propagation crossing the northern hemisphere through mid-September and lowering the MUF of 10 meter F2 propagation crossing the northern hemisphere through late-September.



        There is a slight chance of brief, isolated, geographically focused 6 meter trans-Atlantic sporadic-E propagation from about 1100-2200Z between mid-latitude U.S states and Europe, North Africa and the Middle East. 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 very slight 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 oblique-TEP F2 propagation from the southern tier of US states to the south Pacific (e.g., 3D2, 5W, E5, FK, FO, VK4, VK9, VP6, ZL and ZL7) from about 1900-0300Z. There is a very 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.
        73 Al 4L5A

        Comment

        •  

          Geomagnetic storms and active geomagnetic conditions are about half as likely through mid-July compared to their more frequent occurrence during the equinox seasons.



          Although we are in the prime northern hemisphere 6 meter sporadic-E season through mid-July, solar maximum effects are causing less frequent and shorter duration long distance sporadic-E propagation beyond 2200 km than during solar minimum continuing through 2012.



          The 2300Z Penticton 10.7 cm observed solar flux index was 171 and is likely to remain about the same through Thursday.

          SILSO’s latest Estimated International Sunspot Number was 89 and is likely to remain about the same through Thursday.


          The visible solar disk has one very large, one medium and three very small active regions containing 40 sunspots with a total sunspot area of 470 micro solar hemispheres (about three times the surface area of the Earth).

          Solar wind speed is likely to be near background levels below 400 km/second through at least midday Thursday.



          Geomagnetic activity is likely to be mostly quiet through at least midday Thursday.


          M-class solar flares are likely to cause isolated minor to moderate radio blackouts of propagation paths crossing the sunlit side of the Earth through Thursday.

          No S-class solar radiation storms 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 Thursday . 160 and 80 meter long distance propagation from June through September in the northern hemisphere is always mildly to moderately degraded 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 Thursday. Short path propagation between North America and east Asia after about 0930Z is likely to be normal through Thursday.


          30 meter propagation crossing the auroral ovals and polar regions is likely to be mostly normal through at least 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 mostly normal through at least midday Thursday. Midday 20 meter long distance propagation in the northern hemisphere from June through September is always moderately degraded within several hours of local noon 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 mostly normal through at least midday Thursday. 17 and 15 meter long path propagation from North America to southeast and east Asia from about 1200Z to 1400Z is likely to be normal through Thursday .



          12 and 10 meter propagation is likely to be mostly normal through at least midday Thursday.



          Thermally driven high velocity thermospheric winds at the altitude of the F2 region blow from the high temperature dayside hemisphere to the low temperature nightside hemisphere reducing the volume of neutral atomic oxygen available for ionizing the F2 region during daytime hours, lowering the MUF F2 propagation crossing the northern hemisphere to below the 12 meter band through mid-September and lowering the MUF F2 propagation crossing the northern hemisphere to below the 10 meter band through late September.



          There is a slight chance of brief, isolated, geographically focused 6 meter trans-Atlantic sporadic-E propagation from about 1100-2200Z between mid-latitude U.S states and Europe, North Africa and the Middle East. 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 very slight 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 oblique-TEP F2 propagation from the southern tier of US states to the south Pacific (e.g., 3D2, 5W, E5, FK, FO, VK4, VK9, VP6, ZL and ZL7) from about 1900-0300Z. There is a very 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.

          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 eight minutes later and sunset is two minutes later 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 absorbing D region.
          73 Al 4L5A

          Comment

          •  

            Geomagnetic storms and active geomagnetic conditions are about half as likely through mid-July compared to their more frequent occurrence during the equinox seasons.



            Although we are in the prime northern hemisphere 6 meter sporadic-E season through mid-July, solar maximum effects are causing less frequent and shorter duration long distance sporadic-E propagation beyond 2200 km than during solar minimum continuing through 2022.



            The 2300Z Penticton 10.7 cm observed solar flux index was 191 and is likely to remain about the same through Friday.

            SILSO’s latest Estimated International Sunspot Number was 170 and is likely to remain about the same through Friday.

            The visible solar disk has one very large, three small and four very small active regions containing 63 sunspots with a total sunspot area of 570 micro solar hemispheres (about three times the surface area of the Earth).

            Solar wind speed is likely to be near background levels below 400 km/second through midday Thursday, then rising to 400 km/second or more through late Thursday and improving to near background levels below 400 km/second by midday Friday.



            Geomagnetic activity is likely to be mostly quiet through at midday Thursday, tdegrading to mostly unsettled through late Thursday and improving to mostly quiet before midday Friday.


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

            No S-class solar radiation storms 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 Friday . 160 and 80 meter long distance propagation from June through September in the northern hemisphere is always mildly to moderately degraded 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 Friday. Short path propagation between North America and east Asia after about 0930Z 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 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 through Friday. Midday 20 meter long distance propagation in the northern hemisphere from June through September is always moderately degraded within several hours of local noon 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 mostly normal through Friday. 17 and 15 meter long path propagation from North America to southeast and east Asia from about 1200Z to 1400Z is likely to be normal through Friday .



            12 and 10 meter propagation is likely to be mostly normal through Friday.



            Thermally driven high velocity thermospheric winds at the altitude of the F2 region blow from the high temperature dayside hemisphere to the low temperature nightside hemisphere reducing the volume of neutral atomic oxygen available for ionizing the F2 region during daytime hours, lowering the MUF for F2 propagation crossing the northern hemisphere to less than 24 MHz through mid-September and lowering the MUF for F2 propagation crossing the northern hemisphere to less than 28 MHz through late September.



            There is a slight chance of brief, isolated, geographically focused 6 meter trans-Atlantic sporadic-E propagation from about 1100-2200Z between mid-latitude U.S states and Europe, North Africa and the Middle East. 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 very slight 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 oblique-TEP F2 propagation from the southern tier of US states to the south Pacific (e.g., 3D2, 5W, E5, FK, FO, VK4, VK9, VP6, ZL and ZL7) from about 1900-0300Z. There is a very 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.

            73 Al 4L5A

            Comment

            •  

              Geomagnetic storms and active geomagnetic conditions are about half as likely through mid-July compared to their more frequent occurrence during the equinox seasons.



              Although we are in the prime northern hemisphere 6 meter sporadic-E season through mid-July, solar maximum effects are causing less frequent and shorter duration long distance sporadic-E propagation beyond 2200 km than during solar minimum and continuing through 2022.



              The 2300Z Penticton 10.7 cm observed solar flux index was 206 and is likely to remain about the same through Saturday.

              SILSO’s latest Estimated International Sunspot Number was 170 and is likely to remain about the same through Saturday.

              The visible solar disk has one very large, one medium, three small and four very small active regions containing 100 sunspots with a total sunspot area of 1270 micro solar hemispheres (about eight times the surface area of the Earth).

              Solar wind speed is likely to be near background levels of less than 400 km/second through midday Thursday, then briefly elevated above 400 km/second through late Thursday. Solar wind is likely to return to near background levels of less than 400 km/second from early Friday through midday Saturday.



              Geomagnetic activity is likely to be mostly quiet through midday Thursday, degrading to unsettled to active through late Thursday. Geomagnetic activity is likely to return to mostly quiet levels from early Friday through midday Saturday.


              M-class solar flares are likely to cause isolated minor to moderate radio blackouts of HF propagation paths crossing the sunlit side of the Earth through Saturday.

              There is a slight chance of S1-class minor solar radiation storms through Saturday with minimal impact on propagation crossing polar regions.

              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 from June through September in the northern hemisphere is always mildly to moderately degraded 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 Saturday. Short path propagation between North America and east Asia after about 0930Z is likely to be mostly normal through Saturday.


              30 meter propagation crossing the auroral ovals and polar regions is likely to be mostly normal through midday 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 F2 propagation.

              20 meter propagation crossing the auroral ovals and polar regions is likely to be mostly normal through midday Saturday. 20 meter long distance propagation in the northern hemisphere from June through September is always moderately degraded within several hours of local noon 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 mostly normal through midday Saturday. 17 and 15 meter long path propagation from North America to southeast and east Asia from about 1200Z to 1400Z is likely to be normal through Saturday .



              12 and 10 meter propagation is likely to be mostly normal through midday Saturday.



              Thermally driven high velocity thermospheric winds at the altitude of the F2 region blow from the high temperature dayside hemisphere to the low temperature nightside hemisphere reducing the volume of neutral atomic oxygen available for ionizing the F2 region during daytime hours, lowering the MUF for F2 propagation crossing the northern hemisphere to less than 24 MHz through mid-September and lowering the MUF for F2 propagation crossing the northern hemisphere to less than 28 MHz through late September.



              There is a slight chance of brief, isolated, geographically focused 6 meter trans-Atlantic sporadic-E propagation from about 1100-2200Z between mid-latitude U.S states and Europe, North Africa and the Middle East. 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 very slight 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 oblique-TEP F2 propagation from the southern tier of US states to the south Pacific (e.g., 3D2, 5W, E5, FK, FO, VK4, VK9, VP6, ZL and ZL7) from about 1900-0300Z. There is a very 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.

              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 nine minutes later and sunset is three minutes later 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 absorbing D region.
              73 Al 4L5A

              Comment

              •  

                Geomagnetic storms and active geomagnetic conditions are about half as likely through mid-July compared to their more frequent occurrence during the equinox seasons.



                Although we are in the prime northern hemisphere 6 meter sporadic-E season through mid-July, solar maximum effects are causing less frequent and shorter duration long distance sporadic-E propagation beyond 2200 km than occurred during solar minimum and continuing through 2022.



                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 129 and is likely to remain about the same through Sunday.

                The visible solar disk has one very large, three medium, one small and four very small active regions containing 98 sunspots with a total sunspot area of 1440 micro solar hemispheres (about nine times the surface area of the Earth).

                Solar wind speed is likely to be near background levels of less than 400 km/second through midday Saturday, then elevated above 400 km/second through midday Sunday due to coronal hole high speed stream effects. Solar wind speed is likely to return to near background levels of about 400 km/second after midday Sunday.



                Geomagnetic activity is likely to be mostly quiet through midday Saturday, degrading to unsettled to active through midday Sunday. There is a chance of a minor to moderate geomagnetic storm from late Saturday through early Sunday. Geomagnetic activity is likely to return to quiet to unsettled levels after midday Sunday.

                M-class solar flares are likely to cause a few minutes minor to moderate radio blackouts of propagation paths crossing the sunlit side of the Earth through Sunday. There is a slight chance that an X-class solar flare 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 minor solar radiation storms through Sunday with minimal impact on propagation crossing polar regions.

                160 and 80 meter propagation from North America to VK/ZL and the South Pacific is likely to be normal through Sunday . 160 and 80 meter long distance propagation from June through September in the northern hemisphere is always mildly to moderately degraded 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 Saturday and mostly below normal on Sunday. Short path propagation between North America and east Asia after about 0930Z is likely to be mostly normal through Sunday.


                30 meter propagation crossing the auroral ovals and polar regions is likely to be mostly normal through Sunday with possible below normal intervals from late Saturday through early 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 mostly normal through Sunday with possible below normal intervals from late Saturday through early Sunday. 20 meter long distance propagation in the northern hemisphere from June through September is always moderately degraded within several hours of local noon 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 mostly normal through Sunday with possible below normal intervals from late Saturday through early Sunday. 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 through Sunday .



                12 and 10 meter propagation is likely to be mostly normal through Sunday with possible below normal intervals from late Saturday through early Sunday.



                Thermally driven high velocity thermospheric winds at the F2 region altitude blow from the high temperature dayside hemisphere to the low temperature nightside hemisphere reducing the volume of neutral atomic oxygen available for ionizing the F2 region during daytime hours, lowering the MUF for F2 propagation crossing the northern hemisphere to less than 24 MHz through mid-September and less than 28 MHz through late September.



                There is a slight chance of brief, isolated, geographically focused 6 meter trans-Atlantic sporadic-E propagation from about 1100-2200Z between mid-latitude U.S states and Europe, North Africa and the Middle East. 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 very slight 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 oblique-TEP F2 propagation from the southern tier of US states to the south Pacific (e.g., 3D2, 5W, E5, FK, FO, VK4, VK9, VP6, ZL and ZL7) from about 1900-0300Z. There is a very 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.

                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 ten minutes later and sunset is four minutes later 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 absorbing D region.

                73 Al 4L5A

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