Propagation Forecast Bulletin 44 ARLP044
From Tad Cook, K7RA
Seattle, WA October 28, 2016
To all radio amateurs
At 2313 UTC on October 27 Australia’s Space Weather Services released a geomagnetic warning. On October 28-29 expect unsettled to active geomagnetic conditions due to a coronal hole high speed wind stream.
We saw a decline in solar activity over the past reporting week (October 20-26) compared to the previous week. Average daily sunspot numbers were 18.7, down from 31 in the previous seven days.
Average daily solar flux went from 83.4 to 76.9 over the same two periods.
Geomagnetic indicators were up only slightly, with average daily planetary A index changing from 19.1 to 20.3, and average daily mid-latitude A index moving from 14 to 16.7.
One caveat: the mid-latitude A index values for October 22-24 were estimated, by me. Note the values (left column) for the mid-latitude A index:
It appears that for over 60 hours there was a problem with data from the geomagnetic observations from Virginia, and every place on this table that you see a -1 indicated, the data is missing.
The latest forecast (from Thursday, October 27) predicts solar flux at 78, 77 and 76 on October 28-30, then 78, 80, 85 and 90 on October 31 through November 3, 80 on November 4-6, 78 on November 7-10, 75 on November 11-12, 73 on November 13-16, 75 on November 17-19, then 76, 74, and 73 on November 20-22, then 71, 70, 71 and 77 on November 23-26, then 80 on November 27 through December 3, 78 on December 4-7 and 75 on December 8-9.
Predicted planetary A index is 24, 18 and 16 on October 28-30, then 14, 12, 8 and 6 on October 31 through November 3, 5 on November 4-5, 8 on November 6, 5 on November 7-10, then 10, 15, 18, 10 and 8 on November 11-15, 5 on November 16-18, then 10, 32, 44, 40 and 22 on November 19-23, 18 on November 24-25, then 14, 20 and 12 on November 26-28, 5 on November 29 through December 2, 10 on November 3, 5 on November 4-7 and 10 on November 8.
F.K. Janda, OK1HH gives us his weekly geomagnetic forecast.
“Geomagnetic activity forecast for the period October 28-November 21, 2016
“Geomagnetic field will be:
- Quiet on November 6-7, 16-17
- Mostly quiet on November 5, 15, 18
- Quiet to unsettled on November 1-4, 10-11, 14, 19
- Quiet to active on October 29-31, November 8, 12-13
- Active to disturbed on October 28, November 9, 20-21
Amplifications of the solar wind from coronal holes are expected on November 6-12, 18-21.”
On October 25 I received a couple of emails from Jeff Hartley, N8II of Shepherdstown, West Virginia (FM19cj). Here is his report:
“It has been pretty interesting following band conditions vs. SFI and K indexes. Some trends are clear. The bands down to 30 meters are closing pretty early already affected by the low SFI. 20 was open well to CA until about 0100Z for their QSO party Oct 1-2, now some nights the West Coast is nearly gone by 2320Z.
“I worked 20 10-meter CA QSOs then with flux in the 80s; recently only SA has been workable on 10. Sunday Oct. 23, was a very good day for DX on 20-12 meters. 15 meters was wide open to all of EU by 1300Z.
“I worked EU Russians in the 1, 3, and 4 call areas on 15 CW with the loudest, RA3DS S-9, and R3EV over S-9.
“Stations from Norway and south Sweden were loud, Turkey and Ukraine were also logged. Then, I struggled for a while to work EU on 12 meters (SFI only 78 with K2) through my S5 noise level starting with DL1KSB in Germany at 1421Z. DF0WRTC was S9, but most stations were weak until around 1520Z when G3WGV in England called in.
“Then on SSB, Alex, GD6IA on the Isle of Man was logged S9+15dB at 1534Z followed by Torgeir, LA4UOA in Norway peaking over S9. They both have big antennas, big 12 meters signals. Torgeir reported a 12 meters SSB QSO with VP6AH on Pitcairn Island in the eastern Pacific with an S9 signal, but he faded fast to the noise.
“I worked VP6AH on 9-29 (marginal) and 10-12 (flux over 100) on 12 meter phone.
“I went on to log SSB stations in Germany, England, Italy, Switzerland, Greece, Wales, Netherlands, France, Belgium, and Sardinia on 12 meters until 1615Z.
“I also caught Jeff, TZ4AM in Mali on 12 meter CW at 1637Z who was very weak at first, but built up to about S6 on peaks. During the afternoon I worked Dxpeditions TL0A in Central African Republic on 15 and 17 meter CW, 7P8EUDXF in Lesotho on 20 CW, and V6Z on Truk Island, Micronesia long path on 30 meters CW at 2018Z after a QSO Saturday afternoon on 20 meters long path.
“After some horribly long skip zones on 40 meters this summer, some days there is no skip zone now and others a mere 100-150 miles except during solar storms. When the flux drops from the 90/100s range to the 70s, the skip zone gets longer on 20 meters and signal levels so go down with the path to EU closing much earlier. Also, the backscatter signals from the Eastern USA are down about 10dB which can easily put the weaker ones into the noise.
“I have been chasing National Park units for the 100th anniversary ARRL award and New England, PA, NY, and NJ have been very challenging on 20 meters, but I have made quite a few backscatter QSOs with park stations using very simple low antennas (many just mobile short verticals). I think I have a park in every state now
after a QSO with KL7XK in Glacier Bay NP, AK on 20 phone Oct. 22. AK has been tough to work/find since April.
“The K index went from 5 at 1200Z to 7 at 15Z (strong/G3) today 10/25, and I am still working people (in parks) on 40 mostly to the south. I contacted Algeria, Madagascar, and Central African Republic on 15 phone and there are a few Europeans on 20, but signals are down. EU is working the Far East with big signals on 20.
“73, Jeff N8II Shepherdstown, WV FM19cj.”
Tomas Hood, NW7US the editor of the CQ Magazine Propagation column, sent this late Thursday night:
“Space Weather is now the focus of a new executive order issued on 13 October 2016, as U.S. President Obama takes aim at preparing the nation’s infrastructure for ‘extreme space weather events.’
“Space weather, which covers the Sun-Earth connection and includes the conditions with which radio amateur shortwave communications occur, is a hot area of research and development, and funding. Space weather has the potential to not only affect radio communications but also to affect and disrupt health and safety across the world.
“Issuing an executive order is one way to ensure funding, but it also serves as a reminder that we amateurs are positioned in several ways to participate in the national readiness in the space weather arena: firstly, we are emergency communicators, many of whom are passionate about being prepared to offer their communities with selfless radio communications service, but additionally, being well-educated on space weather science and applications of space weather and radio propagation knowledge. (By the way, for those interested readers, I am still offering a comprehensive space weather and radio propagation course that includes material on forecasting; see http://sunspotwatch.com/swc ) and http://bit.ly/2e5odRP
“Speaking of space weather: this weekend is the 2016 CQ WW SSB contest. I expect some improvement of geomagnetic conditions by the end of the contest period. I don’t think conditions will improve more than offering fair propagation: the sunspot count is low, and the ionosphere needs time to recover from the degradation caused by the constant bombardment of the solar wind over the last few days. Looking further out, I expect better conditions next month for the CQ WW CW contest weekend.
“See you on the air – 73 de NW7US https://fb.me/spacewx.hfradio .”
As mentioned above, this weekend is the CQ World-Wide SSB DX Contest. Check out the rules at http://www.cqww.com/ .
And don’t ignore this: http://bit.ly/2eTxmOy
Page all the way to the bottom for latest readings. The .pdf files are the ones you want.
Note you can use this to see hourly changes in fo F2 values. This shows MUF (Maximum Usable Frequency) for the ionosphere directly above the points on the map.
See a couple of articles about HF intruders:
If you would like to make a comment or have a tip for our readers, email the author at email@example.com.
For more information concerning radio propagation, see the ARRL
- Technical Information Service web page at, http://arrl.org/propagation-of-rf-signals. For an explanation of the 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 October 20 through 26 were 16, 29, 27, 14, 13, 17, and 15, with a mean of 18.7. 10.7 cm flux was 74.7, 77.8, 77.5, 76.9, 75.3, 77.8, and 78, with a mean of 76.9.
Estimated planetary A indices were 3, 2, 6, 9, 16, 60, and 46, with a mean of 20.3. Estimated mid-latitude A indices were 5, 2, 5, 18, 17, 39, and 31, with a mean of 16.7.