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The K7RA Solar Update

10/02/2020

Tad Cook, K7RA, Seattle, reports: Solar wind disturbed HF conditions over the September 24 – 30 reporting week.

Average daily planetary A index rose from 5.1 to 22, while average middle latitude A index went from 5 to 15.6. Average daily sunspot number declined from 1.9 to 1.6; a weak sunspot appeared on only two days, September 23 and 25, with sunspot numbers of 13 and 11, respectively. Average daily solar flux was on the increase, edging up from 71.1 to 73.4.

Predicted solar flux for the next 45 days is 74 on October 2 – 4; 70 on October 5 – 18; 72 on October 19 – 31; 70 on November 1 – 14, and 72 on November 15.

Predicted planetary A index is 12 and 8 on October 2 – 3; 5 on October 4 – 10; 10 on October 11; 5 on October 12 – 19; 10, 18, and 20 on October 20 – 22; 24, 16, 38, and 38 on October 23 – 26; 26, 15, and 10 on October 27 – 29; 5 on October 30 – November 6; 10 on November 7, and 5 on November 8 – 15.

Here’s the geomagnetic activity forecast for October 1 – 27 from OK1HH.

  • The geomagnetic field will be

  • quiet on October 6 – 7

  • quiet to unsettled on October 5, 13 – 16

  • quiet to active on October 1 – 2, (3 – 4; 8 – 9; 12, 17,) 18 – 19

  • unsettled to active October 10 – 11, 20, 22, (24,) 27

  • active to disturbed October 21, 23, (25 – 26)

  • Solar wind will intensify on October 1 – 3, 13 – 14, (15; 20 – 25,) 26 – 27.

Notes: Parentheses means lower probability of activity enhancement.

Here is an article about the European Space Agency Solar Orbiter.

Southgate Amateur Radio News posted a 10-meter report from Tony, G4CJC.

W6MVT in Southern California was pleasantly surprised on September 28 after erecting a new vertical. His first catch was E51JD in the South Cook Islands at 0022 UTC. This was his first SSB DX on 15 meters in many years, although the opening vanished as quickly as it came.

Jeff, N8II reported last Saturday, September 26:

“Solar storm today, early about 1400 – 1500Z. Skip was shorter than normal (NJ and NC on 40) and W9 – land on 20 along with a few ME/NB stations (Maine QSO Party [was] this weekend), but after a good run of 5s, 6s, 7, and 0s on 20 SSB this afternoon, the condx are very poor as of 2015Z. The storm is in full force.”

Ken, N4SO, shared this report from the Alabama Gulf Coast:

“A wealth of information on the NCDXF beacons is available from the Reverse Beacon Network.

“Also, one more beacon on 21.150 MHZ is heard to add to LU4AA, OA4B, YV5B.

“W6WX is often heard at this location near 2300-0000 UTC. His signals are strong enough to hear 100 W and 10 W.”

Sunspot numbers for September 24 – 30 were 0, 11, 0, 0, 0, 0, and 0, with a mean of 1.6. The 10.7-centimeter flux was 73.6, 73.4, 72.6, 74.1, 73.9, 72.8, and 73.3, with a mean of 73.4. Estimated planetary A indices were 19, 20, 27, 24, 33, 16, and 15, with a mean of 22. Middle latitude A index was 11, 17, 18, 16, 21, 14, and 12, with a mean of 15.6.

For more information concerning radio propagation, visit the ARRL Technical Information Service, read “What the Numbers Mean…,” and check out K9LA’s Propagation Page.

A propagation bulletin archive is available. Monthly charts are no longer be updated on this page. For customizable propagation charts, visit the VOACAP Online for Ham Radio website.

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