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The K7RA Solar Update

01/27/2017

Average daily sunspot number rose from 22.6 to 52.7 (from zero two weeks ago) and solar flux from 77.1 to 83.9, for the January 19-25 reporting week.

In addition to this recent uptick, the first sunspot group of Cycle 25 (12620) appeared on December 18. Carl Luetzelschwab, K9LA, has an excellent article about this in the next (February) issue of the Northwest Indiana DX Club newsletter (see http://nwidxclub.weebly.com/newsletters in early February).

 

Tamitha Skov mentioned the new Cycle 25 spot in a recent video: https://www.youtube.com/watch?v=RMEJEwlm4gw


Sunspot 12620 was expected to return (if still active) around January 4-6, but did not show again. It appeared in these alerts on December 21-24:

http://bit.ly/2jZ04Q0


Here is an image from December 22: http://bit.ly/2kt1UbM

 


Predicted solar flux is 82 on January 27, 80 on January 28, 78 on January 29 through February 3, 75 on February 4-7, 76 on February 8, 77 on February 9-12, then 78, 79, and 81 on February 13-15, 83 on February 16-18, then 85, 83 and 82 on February 19-21, 80 on February 22-24, 78 on February 25, 77 on February 26-27, 76 on February 29 through March 1, 75 on March 2-6, and 76 on March 7.


Predicted planetary A index is 15 on January 27-28, 8 on January 29, 12 on January 30-31, then 18, 15, 20 and 16 on February 1-4, 12, 10 and 8 on February 5-7, 5 on February 8-13, 15 on February 14, 10 on February 15-16, 8 on February 17-19, 5 on February 20-22, then 12, 15, 8, 10, 12 and 16 on February 23-28, and 18, 20, 16 and 12 on March 1-4.

 

F.K Janda, OK1HH, sent us this:


“Geomagnetic activity forecast for the period January 27-February 22, 2017


Geomagnetic field will be:

Quiet on January 27, February 1, 11-12, 14, 22

Mostly quiet on January 30, February 9-10, 20-21

Quiet to unsettled on January 31, February 13, 19

Quiet to active on January 28-29, February 3-5, 15, 17

Active to disturbed on February 2, 6-7 (8, 16, 18)


Amplifications of the solar wind from coronal holes are expected on January 26, (31,) February (1-5,) 9, (15)


Remark:

- Parenthesis means lower probability of activity enhancement.”


 

For more information concerning radio propagation, see the ARRL Technical Information Service 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/.


Monthly propagation charts between four USA regions and twelve overseas locations are at http://arrl.org/propagation. Instructions for starting or ending email distribution of ARRL bulletins are at http://arrl.org/bulletins.


Sunspot numbers for January 19 through 25, 2017 were 26, 61, 67, 61, 53, 55, and 46, with a mean of 52.7. 10.7 cm flux was 79.5, 83.2, 86.1, 86.8, 84.1, 82.3, and 85.1, with a mean of 83.9. Estimated planetary A indices were 11, 11, 11, 9, 5, 3, and 6, with a mean of 8. Estimated mid-latitude A indices were 10, 9, 9, 8, 2, 3, and 4, with a mean of 6.4.

 

 



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