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The K7RA Solar Update

07/02/2021

Tad Cook, K7RA, Seattle, reports: Solar activity is strong! For the June 24 – July 1 reporting week, the average daily sunspot number rose from 14 to 34.7, while the average daily solar flux bumped up from 79.3 to 86.9. Both figures represent a dramatic increase in solar activity. The sunspot number last Thursday, June 24, was 56 — above the average of 34.7 and always a good sign.

The planetary A index went from 5.3 to 6.1 over the reporting week, while the average daily middle latitude A index was steady at 6.1.

The predicted solar flux is 94 on July 2 – 6; 90 on July 7 – 8; 85 on July 9 – 11; 82 on July 12 – 14; 80 on July 15 – 18; 82 on July 19; 85 on July 20 – 24; 88 on July 25; 90 on July 26 – 28; 92 on July 29 – August 1; 90 on August 2, and 85 on August 3 – 7.

Predicted planetary A index is 8, 12, 8, 10, and 8 on July 2 – 6; 5 on July 7 – 8; 8 on July 9 – 10; 5, 15, and 12 on July 11 – 13; 5 on July 14 – 20; 8 on July 21; 5 on July 22 – 26; 10 on July 27; 5 on July 28 – 30; 12 on July 31; 5 on August 1 – 4; 8 on August 5 – 6, and 5, 15, and 12 on August 7 – 9.

Here is the geomagnetic activity forecast for July 2 – 29 from F.K. Janda, OK1HH.

The geomagnetic field will be:

  • quiet on July 16 – 17, 24 – 25

  • quiet to unsettled on July 2 – 3, 6 – 7, 9 – 11, 18, 23, 29

  • quiet to active on July 4 – 5, 12, 14 – 15, (19 – 22), 26

  • unsettled to active July (8), 13, 27 – 28

  • active to disturbed nothing forecast

  • Parenthesis means lower probability of activity enhancement.

Jon Jones, N0JK, reports from Kansas (EM28):

“A sporadic-E opening to Europe on 50 MHz on July 1 to the Heartland (Midwest US) on the afternoon of July 1.

“I decoded many Europeans. F6EXV in with a good signal, but difficult getting takers. Finally worked G4PLZ at 1933 UTC. He was my only PSK flag in Europe.

“Even area ops who run kilowatts and big Yagis were having trouble raising Europe, but saw one work F6EXV and possibly EI4DQ. K0TPP (EM48) to the east was having better luck with Europe.

“Here in northeast Kansas, I decoded EA, EI, F, G, and PA2M. EI3KD, EI4DQ had good signals.”

K4ZOT reported on June 28 from EM73 near Atlanta:

“I thought you might be interested in this 6-meter DX, which totally caught me by surprise today.

“I have been a 6-meter enthusiast since I received my license in 1964, when I operated a Layette HA-460 10 W 6-meter transceiver. In all this time I have never worked or heard an African station on 6. I have worked JA several times and other Pacific locations, but never Africa. Much to my total surprise today, June 28, at 1926 UTC, 5T5PA (Mauritania) suddenly popped on the FT8 JTALert Callsigns screen with an audio alert of new DX. Again, to my utter amazement, I worked him on the first call, a distance of 4,241 miles. Not the longest 6-meter DX by far but surprising, at least from this location. I believe he worked one or two other stations, and then he was gone — perhaps only on for 2 or 3 minutes. A wonderful 6-meter DX contact from my station using a five-element Yagi at only 32 feet.

“Six is indeed the ‘Magic Band,’ as it has been for me for 55 years of operation. Best of all, Johannes confirmed the contact in LoTW just a few minutes after we made contact. Thank you, Johannes, a true ham in the best spirit of the hobby.”

KA3JAW reported:

“On Thursday, July 1, at 10:15 AM EDT (1415 UTC), FM DXer Bryce Foster in Mashpee, Massachusetts, received 87.7 RTP Antena-3 Pico da Barrosa, Azores, via two-way Es. The station runs 30 kW vertical polarization. Distance 2,379 air miles. Reception lasted up to 35 minutes with audio identification along with a stream match. This is the first time I heard of a US to Azores link on the FM broadcast band.”

W9NY reported on June 28:

“The propagation on 20 meters between my Dune Acres, Indiana, station and much of Europe and Asiatic Russia beginning last night at 11 PM and continuing for about 2 hours was absolutely amazing. It reminded me of 10 meters at the peak of prior sunspot cycles.

“Around 14.208 I called CQ and worked one station after another, from Finland in the North to Corsica and Greece in the South and all across Russia to several points in Siberia. Many of the signal reports given and received were 20 to 30 dB over S-9. A couple ‘nearly pinned’ the needle on my Icom IC-7610. In fact, I worked many stations running 100 W to simple antennas like a dipole or vertical that were coming in over S-9 and a few stations that were QRP but still producing S-5 to S-7 signals. I have not heard an opening like that in many years, and it was certainly a lot of fun. I probably should have turned on my QRP rig, but I never got around to it.

“Perhaps a harbinger of things to come.

“I did check out 17, 15, 12, 10, and 6, which were all quiet.

“And today there was a fair amount of activity on 10 meters and 6 meters.”

Frank, W3LPL, wrote:

“Propagation through the auroral ovals and polar regions is likely to be mostly normal through Sunday. There is a slight possibility that isolated below-normal intervals may briefly degrade propagation through the auroral ovals and polar regions from midday Saturday through early Sunday.

“We are in the quiet geomagnetic activity season; only about half as many geomagnetically disturbed days occur in June and July compared to the more geomagnetically active equinox seasons.

“Sporadic-E propagation occurs every day during June and July at mid-latitudes in the Northern Hemisphere making long-distance propagation up to 15,000 kilometers (9,300 miles) sporadically available in the 17, 15, 12, 10 and 6 meter bands from sunrise through midnight and occasionally somewhat later.

“The solar flux is likely to be at least 94 through Sunday. Solar active region 2835 has grown to 770 micro-hemispheres (2.3 billion square kilometers, four times the surface area of the Earth), almost as large as the active region that significantly improved HF propagation during late November 2020. Region 2835 is significantly improving HF propagation on 30 and 20 meters during late afternoon, at night, and during the early morning hours, and 17- and 15-meter propagation during the day through early evening. Active regions 2836 and 2837 are slowly and quietly decaying and are having no effect on HF propagation. See this Solar Dynamics Observatory (SDO) image from July 2 @ 1346 UTC.

“160- and 80-meter propagation from North America to VK/ZL and the South Pacific is likely to be seasonably normal through Sunday.

“40-meter short-path propagation to south Asia is likely to be mostly normal at about 0015 UTC through Sunday. 40-meter short path propagation from North America to East Asia after about 0930 UTC is likely to be mostly normal with a slight possibility of isolated below-normal intervals on Saturday.

“30-meter propagation through the auroral ovals and polar regions is likely to be mostly normal, with a slight possibility of isolated below-normal intervals late Saturday. 30 meter propagation is always significantly degraded within a few hours of local noon due to E-region blanketing of long-distance F2 propagation.

“30-meter nighttime, long-distance propagation in the Northern Hemisphere is likely to improve due to increased ionizing solar radiation in the northern high-latitude regions caused by increased sunspot activity, higher solar elevation angles, and much shorter nights with no source of ionizing solar radiation.

“20-meter daytime and evening propagation through the auroral ovals and polar regions is likely to be mostly normal with a slight possibility of isolated below-normal intervals late Saturday.

“20-meter northern transpolar propagation within a few hours of sunrise and sunset is improving with increased solar ionizing radiation on the northern polar region caused by increased sunspot activity and high solar elevation angles 24 hours per day during the midnight sun season. 20 meter long distance propagation is significantly degraded from mid-morning through late afternoon at low and mid-latitudes in the Northern Hemisphere by F1 region midday blanketing of low-angle propagation during the summer.

“20-meter late afternoon, nighttime and early morning long distance propagation in the Northern Hemisphere is likely to improve, due to increased ionizing solar radiation in the northern high-latitude regions, caused by increasing sunspot activity, higher solar elevation angles, and much shorter nights with no source of ionizing solar radiation.

“17- and 15-meter daytime long-distance propagation in the Northern Hemisphere is likely to improve due to increased ionizing solar radiation in the northern high-latitude regions caused by increasing sunspot activity, high solar elevation angles, and long days.

“17-, 15-, 12-, 10-, and 6-meter sporadic-E propagation up to 15,000 km (9,300 miles) is likely to be sporadically available from sunrise through midnight and occasionally later through late July.

“Geomagnetic disturbances caused by coronal hole high-speed stream effects are likely to remain mostly brief, minor, and somewhat less frequent at least through late 2021. The southward-oriented (–Bz) component of the 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 persists in a southward orientation (–Bz) with enhanced IMF field strength for several hours coincident with the effects of an Earth-directed coronal hole high-speed stream. More frequent, longer duration, minor-to-severe geomagnetic storms may be triggered suddenly and unpredictably when the IMF persists in a southward orientation (–Bz) with enhanced IMF field strength for several hours or more coincident with the effects of an Earth-directed fast CME.

“There is a slight possibility that Earth-directed effects of a weak CME and continuing weak coronal hole high-speed stream effects may slightly to moderately enhance IMF field strength, solar wind speed near Earth, and geomagnetic activity. If the weak CME is geo-effective, it may slightly degrade HF propagation through the auroral ovals from midday Saturday through early Sunday. Geomagnetic storms are not likely through Sunday. There is a slight possibility of an M-class solar flare from Friday through Sunday, but its possible effects on HF propagation are likely to be brief and minor.

“Mid-latitude Northern Hemisphere sunset is now 77 minutes later and day length is 163 minutes longer than it was on March 20. Day length and solar elevation angle in the northern polar region are slowly declining through mid-July, due to gradually waning summer solstice effects.”

Sunspot numbers for June 24 – 30 were 11, 25, 16, 32, 50, 56, and 53, with a mean of 34.7. The 10.7-centimeter flux was 80.6, 83.4, 82.4, 87, 88.6, 92.5, and 94.1, with a mean of 86.9.. Estimated planetary A indices were 5, 7, 4, 4, 4, 5, and 14, with a mean of 6.1. Middle latitude A index was 6, 8, 5, 4, 4, 5, and 11, with a mean of 6.1.

For more information concerning radio propagation, visit the ARRL Technical Information Service, read “What the Numbers Mean…,” and check out this propagation page.

A propagation bulletin archive is available. For customizable propagation charts, visit the VOACAP Online for Ham Radio website.

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