Tad Cook, K7RA, Seattle, Washington, reports:

Solar activity took a dramatic plunge over the recent reporting week (June 23 – 29), but geomagnetic activity stayed the same. ARRLField Day weekend saw rising geomagnetic numbers, with the planetary A index at 8, 16, and 23, Friday through Sunday.

On Sunday, June 25, 2022, the geomagnetic activity was a problem, although not severe, with many stations on Field Day reporting increased absorption. The planetary K index peaked at 5 (a big number) at the end of the day on Saturday (UTC time) and continued into the early hours of Sunday, which was early Saturday evening on the West Coast.

This happened because of a crack in the Earth’s magnetosphere, detailed here:

https://bit.ly/3ONZdQ9

Compared to the previous 7 days, average daily sunspot numbers declined from 124.6 to 49.1, while average daily solar flux dropped from 140.5 to 105.3.

Planetary and middle latitude A index averages were both the same as the previous week, all numbers around 11.

The prediction from the United States Air Force (USAF) 557th Weather Wing is not very optimistic, with solar flux peaking at 140 on July 11 – 16.

The prediction shows 10.7-centimeter solar flux at 90 on June 30 and July 1; 95 on July 2; 105 on July 3 – 7; 130 on July 8 – 9; 135 on July 10; 140 on July 11 – 16; 135, 130, 125, and 120 on July 17 – 20; 115, 110, 105, and 100 on July 21 – 24; 95 on July 25 – 26; 100 on July 27 – 29, and 105, 110, 115, and 120 on July 30 through August 2.

Predicted planetary A index is 8, 10, and 8 on June 30 through July 2; 5 on July 3 – 7; 8, 8, 12, and 8 on July 8 – 11; 5 on July 12 – 13; 12 on July 14 – 16; 10 on July 17; 8 on July 18 – 21; 12, 15, 15, and 10 on July 22 – 25, and 5 on July 26 through August 4.

In Friday’s bulletin, look for updated forecasts and observations emailed by readers to k7ra@arrl.net.

Sunspot numbers for June 23 through 29 were 69, 60, 31, 33, 32, 71, and 48, with a mean of 49.1. The 10.7-centimeter flux was 121.4, 115.4, 108.1, 102, 98.2, 96.1, and 96.2, with a mean of 105.3. Estimated planetary A indices were 10, 8, 16, 23, 12, 8, and 6, with a mean of 11.9. Middle latitude A index was 12, 8, 14, 15, 15, 11, and 7, with a mean of 11.7.

A comprehensive K7RA Solar Update is posted Fridays on the ARRL website. For more information concerning radio propagation, visit the ARRL Technical Information Service, read “What the Numbers Mean…,” and check out the Propagation Page of Carl Luetzelschwab, K9LA.

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

Share your reports and observations.

Tad Cook, K7RA, Seattle, Washington, reports:

Hard for me to believe, I had to blink to make sure. On Wednesday, June 8, 2022, for the first time this calendar year there were no sunspots, even though two new sunspot regions appeared on June 4.

Average daily sunspot number declined to 44 from 52.9 last week. Average daily solar flux was only 98, down from 104.3 last week and 158.8 the week before.

Predicted solar flux is 100 on June 9; 105 on June 10 – 11; 110 on June 12 – 14; 115 on June 15 – 17; 120 on June 18; 125 on June 19 – 20; 150 on June 21; 110 on June 22; 100 on June 23 through July 3; 105 on July 4 – 5; 110 on July 6 – 10, and 115 on July 11 – 13.

Assuming the above prediction is true, that would mean average daily solar flux rising from 98 to 107.9 over the next week and 123 the next.

Predicted planetary A index is 5 on June 9 – 15; 10 and 8 on June 16 – 17; 5 on June 18 – 22; 12, 18, 10, and 8 on June 23 – 26; 5 on June 27 through July 9, then 12, 8, 12, and 10 on July 10 – 13.

Despite the recent downturn, Solar Cycle 25 activity exceeds the official forecast, which can be seen at helioforecast.space/solarcycle.

According to Spaceweather.com, May sunspot activity was the highest in 8 years.

To see solar images and useful links, visit bit.ly/3xlrB4 and bit.ly/3x9WNna.

In Friday’s bulletin, look for interesting 6-meter observations.

Sunspot numbers for June 2 – 8 were 59, 52, 75, 57, 45, 23, and 0, with a mean of 44.4. The 10.7-centimeter flux was 100.9, 100.7, 100.9, 98.7, 96.4, 98.4, and 99.9, with a mean of 98. Estimated planetary A indices were 5, 4, 4, 4, 10, 8, and 5, with a mean of 5.7. Middle latitude A index was 5, 4, 4, 5, 10, 11, and 5, with a mean of 6.3.

A comprehensive K7RA Solar Update is posted Fridays on the ARRL website. For more information concerning radio propagation, visit the ARRL Technical Information Service, read “What the Numbers Mean…,” and check out the Propagation Page of Carl Luetzelschwab, K9LA.

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

Share your reports and observations.