Tad Cook, K7RA, of Seattle, Washington, reports for this week’s ARRL Propagation Bulletin:

Sunspot activity seems listless. Average daily sunspot numbers went from 57.3 to 58.4 (see note at the end of the bulletin concerning last week’s averages) while solar flux went from 119.6 to 113.2.

The middle latitude geomagnetic numbers this week seem wrong. See what I mean.

The middle latitude numbers presented here are my own estimates,

trying to correlate with the high latitude and planetary numbers.

Average daily planetary A index went from 18.6 to 10.4, and middle latitude numbers from 8.1 to 9.1.

Predicted solar flux is 120 on October 27; 118 on October 28 – 30; 114 from October 31 through November 2; 112 on November 3 – 5; 118 on November 6 – 9; 115 on November 10 – 12; 112 on November 13 – 14; 110 on November 15; 108 on November 16 – 18; 104 on November 19; 100 on November 20 – 23; 98 on November 24 – 25; 100 on November 26, and 105 on November 27 – 28.

So, the rise in solar flux to 160 in the first week of November presented in the previous two bulletins seems to be gone from the current prediction.

Predicted planetary A index is 10, 14, 18, 22, and 16 on October 27 – 31; 12, 12, and 8 on November 1 – 3; 5 on November 4 – 9; 18, 18, and 15 on November 10 – 12; 5 on November 13 – 17; 25, 18, 17, and 12 on November 18 – 21; 5 on November 22 – 23, and 8, 15, and 20 on November 24 – 26.

Forbes on doomsday flares.

Tabloid news on flares.

In last week’s bulletin, ARLP042, the averages were wrong.

The correct averages for the numbers at the end of the bulletin in ARLP042 were 57.3, 119.6, 10.6, and 8.1 for sunspot number, solar flux, planetary A index, and middle latitude A index, respectively. The wrong numbers were actually from the previous week.

Sunspot numbers for October 20 through 26, 2022, were 33, 60, 55, 65, 46, 72, and 78, with a mean of 58.4. The 10.7-centimeter flux was 115.8, 109.4, 105, 108.4, 114.8, 116.3, and 122.4, with a mean of 113.2. Estimated planetary A indices were 7, 5, 27, 16, 8, 5, and 5, with a mean of 10.4. Middle latitude A index was 5, 4, 24, 15, 7, 5, and 4, with a mean of 9.1.

Send your tips, questions, or comments to k7ra@arrl.net.

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, of Seattle, Washington, reports for this week’s ARRL Propagation Bulletin:

Sunspot activity took quite a plunge over this reporting week (October 13 – 19). Average daily sunspot numbers declined from 114.9 to 57.3, while equivalent solar flux values went from 155.3 to 119.6.

Geomagnetic indicators were slightly lower, with the average planetary A index going from 13.3 to 10.6, and middle latitude A index from 10.4 to 8.1.

I should note that the middle latitude A index for October 18 – 19 are my own estimates. The Fredericksburg, Virginia, magnetometer was offline for a 24-hour period spanning both days.

The Wednesday forecast of solar flux shows a peak at 160 during the first week in November.

Predicted daily flux values are 110 on October 20 – 26; 115 and 150 on October 27 – 28; 155 on October 29 – 30; 152 on October 31; 160 on November 1 – 8; 150, 140, and 135 on November 9 – 11; 130 on November 12 – 13; 135 on November 14; 138 on November 15 – 17, and 140 on November 18 – 21.

Predicted planetary A index is 12 and 10 on October 20 – 21; 5 on October 22 – 23; 10, 5, 8, and 12 on October 24 – 27; 15, 12, and 20 on October 28 – 30; 15 on October 31 through November 1; 18, 15, 12, 20, and 8 on November 2 – 6; 5 on November 7 – 9; 18 on November 10 – 11; 15 and 8 on November 12 – 13; 5 on November 14 – 15; 12 on November 16 – 17; 8 on November 18, and 5 on November 19 – 21.

Despite the lower solar activity, worldwide 10-meter propagation has been very good this week, probably helped by seasonal variations as we head deeper into the fall season.

In Friday’s bulletin, expect reports from readers.

Sunspot numbers for October 13 through 19 were 57, 51, 50, 59, 84, 50, and 50, with a mean of 114.9. The 10.7-centimeter flux was 130, 120.5, 115.1, 119.2, 125.6, 113.9, and 113.2, with a mean of 155.3. Estimated planetary A indices were 5, 18, 18, 16, 6, 6, and 5, with a mean of 13.3. Middle latitude A index was 4, 16, 15, 11, 4, 4, and 3, with a mean of 10.4.

Send your tips, questions, or comments to k7ra@arrl.net.

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, of Seattle, Washington, reports for this week’s ARRL Propagation Bulletin:

Sunspot numbers and solar flux increased this week (September 29 through October 5), as expected, with the solar cycle progressing toward a probable peak in the summer of 2025.

Average daily sunspot number increased from 105.1 to 111.4, and average daily 10.7-centimeter solar flux increased from 138.4 to 149.2.

Compare it to a year ago, when average daily sunspot number was just 59.4 and solar flux was 89.8.

Predicted solar flux is 158 and 156 on October 6 – 7; 154 on October 8 – 9; 152, 150, 148, and 140 on October 10 – 13; 130 on October 14 – 15; 135 on October 16 – 17; 140 on October 18; 145 on October 19 – 21; 150 on October 22 – 23; 145, 140, and 135 on October 24 – 26; 145 on October 27 – 28; 150 on October 29; 155 on October 30 – 31; 145 on November 1, and 135 on November 2 – 4.

Predicted planetary A index is 12, 14, 10, 12, and 8 on October 6 – 10; 5 on October 11 – 12; 8 on October 13 – 14; 10 on October 15 – 16; 8 on October 17 – 19; 12 on October 20 – 21; 8 on October 22 – 29; 20, 12, and 10 on October 30 through November 1, and 8 on November 2 – 10.

On October 2, www.spaceweather.com announced “a big dangerous sunspot,” AR3112, one of the biggest in years, had rotated over the sun’s eastern horizon. They predict this could produce 2 weeks of high solar activity.

For the latest from Space Weather Woman Dr. Tamitha Skov, WX6SWW, visit:

Sunspot numbers for September 29 through October 5, 2022, were 56, 74, 100, 102, 144, 153, and 151, with a mean of 111.4. The 10.7-centimeter flux was 137.2, 137.1, 147.9, 153.9, 155.1, 152.4, and 161, with a mean of 149.2. Estimated planetary A indices were 7, 13, 3, 12, 24, 16, and 14, with a mean of 12.7. Middle latitude A index was 7, 12, 2, 9, 16, 13, and 11, with a mean of 10.

Send your tips, questions, or comments to k7ra@arrl.net.

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.

The proposed date for the startup of the Sunday night informational net will be Sunday November 6, 2022 @ 8:00 pm. Keep checking here on the web site for any additional information that may came up.