The Australian Space Weather Forecasting Centre issued the following Geomagnetic Disturbance Warning #23/74 at 2321 UT on November 29, 2023:

“Several coronal mass ejections (CMEs) are expected to impact Earth on November 30 and December 1, 2023. Two CMEs were observed on November 27 that were expected to arrive on November 30, followed shortly by a very mild, glancing blow from a third. One or possibly two halo CMEs were observed on November 29, which are Earth-directed. It is likely that all or some of these CMEs will combine on their trajectory toward Earth, making it difficult to pinpoint an exact arrival time. However, G3-G4 geomagnetic conditions are possible over this period.”

Over the past reporting week, 10 new sunspot groups appeared. There were three on November 23, one each day on November 24 – 26, another on November 28, and three more on November 29.

Solar numbers increased, with the average daily sunspot number rising dramatically from 83.3 to 165.9, doubling from the previous week.

The average daily solar flux rose from 146 to 181.5.

Geomagnetic numbers rose slightly, with the planetary A index changing from 10.1 to 11.6, and the middle latitude number changing from 7.3 to 7.6.

Predicted solar flux is 175 on November 30; 170 on December 1; 165 on December 2 – 3; 160 on December 4; 150 on December 5 – 6; 140 on December 7 – 8; 145 on December 9 – 10; 140 on December 11 – 16; 150 on December 17, and 160 on December 18 – 28.

Predicted planetary A index is 30, 56, and 22 on November 30 through December 2; 10, 10, 12, 10, and 10 on December 3 – 7; 5 on December 8 – 11; 10 and 8 on December 12 – 13; 5 on December 14 – 17; 15, 25, 8, and 5 on December 18 – 21, and 20, 10, 10, 8, and 5 on December 22 – 26.

Watch a new video from Dr. Tamitha Skov, WX6SWW, about solar storms at https://youtu.be/qiHtkXfZnQo. Sunspot numbers for November 23 – 29, 2023, were 176, 184, 179, 169, 159, 130, and 164, with a mean of 83.3. The 10.7-centimeter flux was 194.2, 178, 176.4, 180.2, 187.3, 183.5, and 170.6, with a mean of 146. Estimated planetary A indices were 7, 7, 38, 10, 7, 7, and 5, with a mean of 10.1. Middle latitude A index was 4, 5, 18, 9, 2, 6, and 9, with a mean of 7.3.

Because of the Thanksgiving holiday, this bulletin preview is moved back a day and does not have the full Thursday-through-Wednesday data; that will appear in Friday’s bulletin.

Last weekend, conditions during the ARRL November Phone Sweepstakes were great because geomagnetic activity was so low. Planetary A index was 3 and 4, and even high-latitude indicators were low. Alaska’s college A index was 2 and 1.

Solar activity has been up for the past few days. Starting on November 17, a new sunspot group appeared every day, and on Monday, November 20, six new sunspot groups emerged. Sunspot numbers on Monday and Tuesday were 127 and 138, which is the first time the daily sunspot number has been more than 100 since November 3.

Predicted solar flux is 172, 175, and 177 on November 22 – 24; 180 on November 25 – 27; 185 on November 28 – 29; 155 on November 30 – December 1; 150, 152, 148, and 145 on December 2 – 5; 140 on December 6 – 8; 145 on December 9 – 10, and 140 on December 11 – 17. Predicted planetary A index is 14, 12, and 8 on November 22 – 24; 5 on November 25 – 26; 10 and 8 on November 27 – 28; 5 on November 29 – December 3; 12, 16, 12, and 10 on December 4 – 7; 5 on December 8 – 11; 10 and 8 on December 12 – 13, and 5 on December 14 – 17.

Solar activity was lower this week, November 9 – 15, 2023, with the average daily sunspot numbers dropping from 89.7 to 80.1, and the average daily solar flux from 151.7 to 133.8.

If those numbers seem a little low lately, we should check the bulletin from the same week last year. In the November 18, 2022, bulletin, the average daily sunspot number changed from 79.8 to 72.3, so a year later we are definitely trending higher.

Geomagnetic indicators were also lower, with the planetary A index changing from 22.3 to 10.4, and the middle latitude A index from 14.6 to 8.6.

A single new sunspot group appeared on November 10, another on November 12, one more on November 13, and another on November 14.

The predicted solar flux is 120, 118, 116, 120, and 122 on November 16 – 20; 125 on November 21 – 22; 135 on November 23 – 25; 140, 148, and 152 November 26 – 28; 155 on November 29 through December 1; 152, 150, 148, and 145 on December 2 – 5; 140 on December 6 – 8; 145, 135, 130, and 125 on December 9 – 12, and 120 on December 13 – 15.

The predicted planetary A index is 10 and 8 on November 16 – 17; 5 on November 18 – 19; 8 on November 20 – 21; 5, 12, 18, 20, and 12 on November 22 – 26; 8 on November 27 – 28; 5 on November 29 through December 3; 10, 16, 12, and 10 on December 4 – 7; 5 on December 8 – 9; 8 on December 10 – 13, and 5 on December 14 – 18.

Check this site for an update of current conditions on various bands: https://dr2w.de/dx-propagation/ Sunspot numbers for November 9 – 15, 2023, were 93, 93, 85, 78, 85, 86, and 41, with a mean of 80.1. The 10.7-centimeter flux was 138.7, 143.9, 141.5, 137.2, 132.7, 123.8, and 118.9, with a mean of 133.8. Estimated planetary A indices were 12, 10, 5, 12, 16, 6, and 12, with a mean of 10.4. The middle latitude A index was 8, 7, 4, 10, 5, and 11, with a mean of 8.6.

This reporting week, ending on November 8, 2023, saw six new emerging sunspot groups; one on each day, except November 6.

Solar activity improved, with the average daily sunspot number increasing from 76.7 to 89.7. The average daily solar flux rose from 137.5 to 151.7.

Geomagnetic activity increased. The average daily planetary A index changed from 15.9 to 22.3 and the middle latitude A index rose from 11.9 to 14.6.

The most active days were Sunday and Monday when the planetary A index was 57 and 40.

Predicted solar flux is 146 on November 9; 145 on November 10 – 13; 150 on November 14 – 16; 123 and 123 on November 17 – 18; 125 on November 19 – 22; 130 on November 23 – 26; 132, 134, and 134 on November 27 – 29; 136 on November 30 through December 2, and 140 and 138 on December 3 – 4.

Predicted planetary A index is 12, 10, and 8 on November 9 – 11; 5, 5, 8, and 10 on November 12 – 15; 5 on November 16 – 21; 15, 10, and 15 on November 22 – 24; 15, 20, 15, and 8 on November 25 – 28, and 5 on November 29 through December 5.

Read about the recent aurora at https://bit.ly/467cs6d. Sunspot numbers for November 2 through 8, 2023, were 113, 106, 95, 81, 67, 74, and 92, with a mean of 89.7. The 10.7-centimeter flux was 158.4, 156.1, 155.3, 154.8, 146.2, 145.1, and 145.7, with a mean of 151.7. Estimated planetary A indices were 7, 4, 14, 57, 40, 18, and 16, with a mean of 22.3. Middle latitude A index was 4, 3, 12, 30, 27, 11, and 15, with a mean of 14.6.

Seven new sunspot groups emerged this reporting week. There were two on October 26, one on October 27, another on October 28, two more on October 31, and another on November 1.

Average daily sunspot numbers rose from 41.9 to 76.7, while the average daily solar flux increased from 123.5 to 137.5.

Predicted solar flux is 160, 162, and 162 on November 2 – 4; 160, 157, 150, 148, 136, 138, 136, and 134 on November 5 – 12; 130 on November 13 – 15; 125, 123, and 120 on November 16 – 18; 125 on November 19 – 22, and 130 on November 23 – 26.

Predicted planetary A index is 8, 5, 8, 12, 8, and 5 on November 2 – 7; 12 on November 8 – 9; 8 on November 10; 5 on November 11 – 13; 8 and 10 on November 14 – 15; 5 on November 16 – 21, and 15, 10, 15, 15, and 20 on November 22 – 26.

There might be an early peak of Solar Cycle 25. Read about it at https://bit.ly/3FF26jh and https://bit.ly/40ndQQN. Sunspot numbers for October 26 through November 1 were 57, 66, 70, 61, 62, 116, and 105, with a mean of 76.7. The 10.7-centimeter flux was 126.4, 127.5, 128, 135.2, 139.7, 147.3, and 158.6, with a mean of 137.5. Estimated planetary A indices were 23, 11, 19, 28, 12, 9, and 9, with a mean of 15.9. Middle latitude A index was 18, 9, 13, 21, 10, 6, and 6, with a mean of 11.9.