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The K7RA Solar Update

01/01/2021

Tad Cook, K7RA, Seattle, reports: Solar Ccle 25 is progressing normally, and with the new year, my outlook is optimistic. Solar minimum occurred just over a year ago (December 2019), and now we see very few days with no sunspots.

Both of the current sunspot groups (2794 and 2795) are about to slip across the sun’s western horizon.

Average daily sunspot number this past week was 27.1, up from 10.3 the previous week. Average daily solar flux rose from 82.8 to 86.4.

Predicted solar flux over the next 30 days is 81 and 80 on January 1 – 2; 79 on January 3 – 4; 78 on January 5 – 8; 84 on January 9 – 14; 85, 86, and 87 on January 15 – 17; 88 on January 18 – 28; 87 on January 29, and 86 on January 30. It then dips to 84 on February 1 – 10.

Predicted planetary A index is 5 on January 1 – 2; 8 and 5 on January 3 – 4; 8 on January 5 – 7; 5 on January 8 – 17; 10 on January 18 – 20; 8 on January 21; 5 on January 22 – 24; 10 on January 25, and 5 on January 26 – 30.

When I check the STEREO website any possible coming activity, I don’t see anything obvious, but do not be surprised if new activity appears soon — perhaps before mid-January — along with the predicted higher flux values.

Here’s the geomagnetic forecast from J.K. Janda, OK1HH, of the Czech Propagation Interest Group for January 1 – 26, 2021. The geomagnetic field will be:

  • quiet on January 1, 3, 13 – 14

  • quiet to unsettled on January 2, 4, 8, 10, 12, 15 – 16, 21, 25 – 26

  • quiet to active on January 5 – 7, 9, 11, 17, 22 – 23

  • unsettled to active January 20, 24

  • active to disturbed January 18 – 19

  • Solar wind will intensify on January (1-3, 7-9, 19-20,) 21-22, (23, 25-26)

Notes:

Parentheses mean lower probability of activity enhancement.

The predictability of changes is lower again, as there are ambiguous and changing indications.

Wishing a Happy New Year, positive thinking, and negative tests!

(The Czech Propagation Interest Group has been compiling this geomagnetic activity weekly forecasts since January 1978.)

Ted Leaf, K6HI, of Kona, Hawaii, shared another optimistic report on new Solar Cycle 25. Here’s more on the NCAR prediction and the solar clock.

Sunspot numbers for December 24 – 30, 2020, were 25, 30, 31, 26, 26, 26, and 26, with a mean of 27.1. The 10.7-centimeter flux was 87.4, 87.7, 87.9, 87.8, 87.2, 84.2, and 82.8, with a mean of 86.4. Estimated planetary A indices were 10, 5, 4, 6, 7, 7, and 9, with a mean of 6.9. Middle latitude A index was 7, 4, 3, 4, 6, 5, and 6, with a mean of 5.

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. For customizable propagation charts, visit the VOACAP Online for Ham Radio website.

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