QST de W1AW
Propagation Forecast Bulletin 2 ARLP002
From Tad Cook, K7RA
Seattle, WA January 8, 2016
To all radio amateurs
SB PROP ARL ARLP002
ARLP002 Propagation de K7RA
Solar indices were down over the past reporting week (December 31,Â 2015 through January 6, 2016) with average daily sunspot numbersÂ down from 49.6 to 41 and average daily solar flux down from 122.3 toÂ 98.2.
Average daily planetary A index declined from 21.7 to 16.6 andÂ average mid-latitude A index from 12.6 to 10.6.
Predicted solar flux is 105 on January 8-10, 100 on January 11-12,Â 95 on January 13-14, then 105, 110 and 115 on January 15-17, 120 onÂ January 18-21, then 115, 110, 105 and 110 on January 22-25, 115 onÂ January 26-27, 110 on January 28, and 105 on January 29 throughÂ February 3. Solar flux then peaks for the near terms at 115 onÂ February 5-6 and again at 120 on February 14-17.
Predicted planetary A index is 8 on January 8, 5 on January 9-11, 12Â on January 12, 8 on January 13, 5 on January 14-20, then 8, 15, 12Â and 8 on January 21-24, 5 on January 25-30, 12 on January 31, 8 onÂ February 1, 20 on February 2-3, 12 on February 4, 8 on February 5Â and 5 on February 6-16.
Petr Kolman, OK1MGW predicts the geomagnetic field will be quiet toÂ unsettled on January 8-9, active to disturbed on January 10, quietÂ to active January 11, quiet to unsettled January 12-14, mostly quietÂ January 15-17, quiet January 18-19, quiet to unsettled JanuaryÂ 20-22, mostly quiet January 23, quiet on January 24-26, quiet toÂ active January 27-28, quiet to unsettled January 29-30, mostly quietÂ January 31, quiet to active February 1-2, and quiet to unsettled
Petr is less certain about his forecast over the period JanuaryÂ 15-19.
He predicts increased solar wind over January 10-11 and 27-28.
At 2302 UTC on January 4, Australia’s Space Weather Services issuedÂ a geomagnetic warning:
“Coronal hole effects are likely to result in periods of activeÂ geomagnetic conditions in the Australian region, with minor stormÂ levels at higher latitudes.
“Increased geomagnetic activity expected due to coronal hole highÂ speed wind stream from 06-07 January 2016.”
You can subscribe to their various alerts atÂ http://listserver.ips.gov.au/mailman/listinfo/
Sure enough, as predicted there was increased geomagnetic activityÂ on January 6-7. The mid-latitude A index on those dates was 12 andÂ 11, the planetary A index was 17 and 14 and the College A indexÂ (Fairbanks, Alaska) values were 27 and 22.
Popular Science this week has a basic article about sunspots:Â http://www.popsci.com/what-is-sunspot
There was a geomagnetic storm last week, just in time for New Year’sÂ and Straight Key Night:Â http://bit.ly/1VPrMei
Participants in Straight Key Night noted the poor propagationÂ overnight, but said that during New Year’s Day conditions improved.
See http://www.arrl.org/contests/soapbox and select 2016 ARRLÂ Straight Key Night in the drop-down.
WB2AWQ noted that he used a keyboard, which was actually a piece ofÂ wood with five telegraph keys attached.
Don’t miss comments from W0AAA about past SKNs as well as hisÂ QRZ.com page.
As usual for SKN, many stations used various vintage gear and keys.
If you would like to make a comment or have a tip for our readers,Â email the author at email@example.com.
- For more information concerning radio propagation, see the ARRLÂ Technical Information Service web page at,
- For an explanation of theÂ numbers used in this bulletin, seeÂ http://arrl.org/the-sun-the-earth-the-ionosphere.
- An archive of pastÂ propagation bulletins is atÂ http://arrl.org/w1aw-bulletins-archive-propagation.
- More goodÂ information and tutorials on propagation are at http://k9la.us/.
My own archives of the NOAA/USAF daily 45 day forecast for solarÂ flux and planetary A index are in downloadable spreadsheet format atÂ http://bit.ly/1VOqf9B and http://bit.ly/1DcpaC5 .
Click on “Download this file” to download the archive, and ignoreÂ the security warning about file format. Pop-up blockers may suppressÂ the download.
Monthly propagation charts between four USA regions and twelveÂ overseas locations are at http://arrl.org/propagation.
Instructions for starting or ending email distribution of ARRLÂ bulletins are at http://arrl.org/bulletins.
Sunspot numbers for December 31 through January 6 were 18, 40, 52,Â 50, 60, 29, and 38, with a mean of 41. 10.7 cm flux was 96.2, 98.4,Â 100, 101.9, 95.3, 95.2, and 100.2, with a mean of 98.2. EstimatedÂ planetary A indices were 43, 27, 10, 7, 5, 7, and 17, with a mean ofÂ 16.6. Estimated mid-latitude A indices were 25, 17, 6, 5, 4, 5, andÂ 12, with a mean of 10.6.