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The K7RA Solar Update

11/11/2016

At 0002 UTC on November 9, this geomagnetic warning was distributed by Australia’s Space Forecast Centre:

SUBJ: SWS GEOMAGNETIC DISTURBANCE WARNING 16/48 ISSUED AT 0002UT/09 NOVEMBER 2016 BY THE AUSTRALIAN SPACE FORECAST CENTRE.

INCREASED GEOMAGNETIC ACTIVITY EXPECTED DUE TO CORONAL HOLE HIGH SPEED WIND STREAM AND POSSIBLE GLANCING BLOW FROM CME ASSOCIATED WITH 05NOV FILAMENT ON 09-10 NOVEMBER 2016

GEOMAGNETIC ACTIVITY FORECAST

09 Nov: Quiet to Minor Storm

10 Nov: Active

 

Later on the same day, the USAF Space Weather operation Ap forecast predicts the disturbance perhaps a few days later. The USAF forecast was issued about 21 hours later than the Australian forecast. Now we have an updated forecast from Thursday, November 10.

 

At 0005 UTC on November 11 a similar warning was issued.

 

INCREASED GEOMAGNETIC ACTIVITY EXPECTED DUE TO CORONAL HOLE HIGH SPEED WIND STREAM FROM 11-12 NOVEMBER 2016.

GEOMAGNETIC ACTIVITY FORECAST

11 Nov: Unsettled with possible Active to Minor Storm periods

12 Nov: Active to Minor Storm

 

Average daily sunspot number over the past week (November 3-9) doubled from 9.1 to 18.7, compared to the previous seven days. Average daily solar flux changed only marginally from 77.5 to 76.9. Geomagnetic indices were lower, with average planetary A index changing from 18.1 to 6.4, and mid-latitude A index (measured at Wallops Island, Virginia) moved from 13.4 to 4.3.

 

Predicted planetary A index is 26, 28, 18 and 12 on November 11-14, then 8, 5, 3 and 5 on November 15-18, then 8, 15, 54, 42 and 24 on November 19-23, then 18, 22, 18, 12 and 10 on November 24-28, 8 on November 29-30, 5 on December 1-3, then 8, 20 and 8 on December 4-6, 10, 12 and 20 on December 7-9, then 18, 10 and 8 on December 10-12, 5 on December 13-15, then 8, 15, 54, 42 and 24 on December 16-20, and 18, 22 and 18 on December 21-23.

 

Predicted solar flux is 80 on November 11-13, 85 on November 14-15, 90 on November 16-17, then 80, 77 and 75 on November 18-20, 78 on November 21-22, 79 on November 23-25, 78 on November 26, 77 on November 27-28, 76 on November 29-30, 77 on December 1-3, 75 on December 4-5, then 78 on December 6-15, 77 and 75 on December 16-17, then 78 on December 18-19 and 79 on December 20-22.

 

 

F.K. Janda, OK1HH, of the Czech Propagation Interest Group sends us this geomagnetic activity forecast for the period November 11-December 7, 2016.

Geomagnetic field will be:

Quiet on November 15-17, December 1-4

Mostly quiet on November 14, 19, 28, December 7

Quiet to unsettled on November 11, 18, 26-27, December 5

Quiet to active on November 12-13, 20, 24, 29-30, December 6

Active to disturbed on November 21-22, (23, 25)

 

Increased solar wind from coronal holes are expected on November 11-13, 18-20

 

Remark:

- Parenthesis means lower probability of activity enhancement.

- Reliability of predictions is reduced at present.

 

 

Jeff Hartley, N8II, of Shepherdstown, West Virginia checked in with observations on November 10:

“Nothing too exciting has happened on the bands until today. SFI has been running around 76-78 most of the week with quiet geomagnetic conditions, but the limited daylight now is really limiting polar path DX with just a few JAs and R0XR in Eastern Asiatic Russia logged on 20 around 2300Z.

 

“Signals are good from Australia most mornings around 1230Z on 20 meters. Fifteen meters is open most days to the Mediterranean area of EU extending up to England with some strong signals from that area. Today, November 10, was pretty typical with signals improving around 1600Z to EU with Peter, MI1ERL, in Northern Ireland being the loudest worked at S9 +20 dB on peaks. I then checked 12 meter CW to find ZD8W on Ascension Island in the south Atlantic with a Spanish station heard calling him. I logged ZD8W, then proceeded to work several Spanish stations with good signals along with two from Portugal including CT1DGE running 5 watts. EA8DO and EA8TL in the Canary Islands were both S9+. But the big surprise of the day was a call from Finland, OH2LZC, at 1639Z, also on 12 meters. There must have been some auroral Es. Niko was only running 200 W to an 80-meter loop antenna and was S5 on peaks with deep, rapid QSB.”

 

 

Ran across this interesting piece today about reconstructing sunspot data from 400 years ago: http://bit.ly/2fpj8EK

 

 

I can’t vouch for the source, but here is an interesting article about cracks in the magnetosphere. It mysteriously arrived from some kind of e-mail anonymizer: http://bit.ly/2eXL6Xt

 

 

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

 

Sunspot numbers for November 3 through 9 were 23, 25, 24, 23, 24, 0, and 12, with a mean of 18.7. 10.7 cm flux was 75.6, 76.7, 76.7, 76.2, 76.5, 76.9, and 79.9, with a mean of 76.9. Estimated planetary A indices were 18, 5, 3, 5, 4, 3, and 7, with a mean of 6.4. Estimated mid-latitude A indices were 12, 3, 2, 4, 2, 2, and 5, with a mean of 4.3.

 



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