The K7RA Solar Update

"ASWFC GEOMAGNETIC DISTURBANCE WARNING ISSUED AT 0211UT/09 AUGUST 2024 BY THE AUSTRALIAN SPACE WEATHER FORECASTING CENTRE.

"Recent CME activity is expected to increase geomagnetic activity from mid 09-Aug and on 10-Aug. Further CME activity on 08-Aug is now expected to also increase geomagnetic activity on 11-Aug.

"INCREASED GEOMAGNETIC ACTIVITY EXPECTED DUE TO CORONAL MASS EJECTION FROM 09-12 AUGUST 2024 GEOMAGNETIC ACTIVITY FORECAST

09 Aug: G0, chance of G1 late in UT day

10 Aug: G1-G2

11 Aug: G1-G2

12 Aug: G1 periods early in UT day, then G0

Solar activity jumped over the past reporting week (August 1-7) with average daily sunspot number rising from 208.9 to 222.3 and solar flux from 207.3 to 255.3.

Spaceweather.com reported that sunspot numbers have reached a 23-year high. On August 8 the daily sunspot number climbed to 332. We must be at the peak of cycle 25, but I hope we have more to go.

Geomagnetic numbers were fundamentally unchanged, with average daily planetary A index shifting from 14 to 15.7 and middle latitude index from 13.1 to 13.4.

Seven new sunspot groups emerged. One on August 1, two on August 2, three on August 4 and one on August 7.

Predicted solar flux shows 300 on August 9-10, then 260, 250, 270 and 280 on August 11-14, then 300, 205, 200 and 185 on August 15-18, 180 on August 19-22, 200 and 210 on August 23-24, 220 on August 25-26, 235 on August 27-28, 245 on August 29- 30, and 240 on August 31 through September 7, then 230, 225 and 210 on September 8-10, 205 on September 11-12, then 200 and 185 on September 13-14, and 180 on September 15-18.  

Predicted planetary A index is 34, 52, 36 and 22 on August 9-12, 5 on August 13-21, then 10 and 8 on August 22-23, 5 on August 24 to September 11, 8 on September 12, and 5 on September 13-17.

Weekly Commentary on the Sun, the Magnetosphere, and the Earth's Ionosphere for August 8, 2024 from F.K. Janda, OK1HH.

"Of the five sunspot groups that moved from the southeast quadrant of the solar disk to the southwest during the past seven days, two of them (AR 3774 and AR 3777) are seeing moderate eruptions almost daily.

"There were three such eruptions on August 7 alone, while CMEs were observed in two of them. Their arrival on Earth is scheduled for August 10. It could cause a geomagnetic disturbance in the G2 (moderate) to G3 (strong) level. Which could be good news for the initial stage of development of decameter wave propagation conditions.

"But if the ejected clouds of particles of solar origin are faster and arrive already on the night of August 9-10, this is bad news for subsequent developments. We'll see.

"In a few days, the current largest active region AR 3780 will be located in the southwest quadrant of the solar disk.

"Sunspot activity in July was the highest it has been in 23 years.  The average monthly sunspot number for July 2024 was 196.5. The last time this happened was in 2001. The last smoothed average can be calculated for this January: R12 = 131.1."

Solar Terrestrial Centre of Excellence Newsletter. https://bit.ly/4dfSj1Y

The Worked All Europe CW DX Contest is this weekend. https://www.darc.de/der-club/referate/conteste/wae-dx-contest/en/

Predicting solar max: https://bit.ly/3AafcFu

Flare August 8-9: https://bit.ly/4dDAPg1

Aurora: https://bit.ly/3WWq3f2

From David Moore:  https://www.sciencedaily.com/releases/2024/07/240730134746.htm

Sunspot number hits 23 year high:

https://bit.ly/3LURJej

https://bit.ly/46AGnFL

https://aussiedlerbote.de/en/active-sun-many-sunspots-are-visible/

https://bit.ly/3AdejvP

Send your tips, reports, observations, questions and comments to k7ra@arrl.net .  When reporting observations, don't forget to tell us which mode you were operating.

For more information concerning shortwave radio propagation, see http://www.arrl.org/propagation and the ARRL Technical Information Service web page at, http://arrl.org/propagation-of-rf-signals .

For an explanation of numbers used in this bulletin, see http://arrl.org/the-sun-the-earth-the-ionosphere .

An archive of past propagation bulletins is at http://arrl.org/w1aw-bulletins-archive-propagation . 

More good information and tutorials on propagation are at http://k9la.us/ .

Also, check this: https://bit.ly/3Rc8Njt .

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Sunspot numbers for August 1 through 7, 2024 were 260, 232, 217, 194, 189, 222, and 242, with a mean of 222.3. 10.7 cm flux was 234.4, 247.1, 244.6, 240.8, 247.3, 270, and 303.2, with a mean of 255.3. Estimated planetary A indices were 22, 9, 10, 46, 10, 6, and 7, with a mean of 15.7. Middle latitude A Index was 22, 9, 9, 28, 10, 8, and 8, with a mean of 13.4.