ZCZC AP47
QST de W1AW
Propagation Forecast Bulletin 47 ARLP047
From Tad Cook, K7VVV
Seattle, WA November 15, 2002
To all radio amateurs
SB PROP ARL ARLP047
ARLP047 Propagation de K7VVV
Solar flux and the sunspot count increased this week by a modest amount. Geomagnetic indices were still somewhat unsettled, but the average daily A index for the week dropped from 19.3 to 12.
This quieting of geomagnetic activity is nice for HF operators, but it looks like we could be in for more upset this weekend. Currently the predicted planetary A index for Friday through Monday is 20, 30, 25 and 15.
It would be nice to predict better conditions for the ARRL Phone Sweepstakes this weekend, but at least it is a domestic contest. It's not like trying to work DX over a polar route, which becomes difficult during high geomagnetic activity.
Why is geomagnetic activity likely to rise? There is a coronal hole rotating into a position favorable for affecting the earth, plus sunspot regions 191 and 192 are potential sources of flares. Region 197 also has flare potential, and it is rotating into view.
But not everyone dreads the solar wind and high geomagnetic activity. Jon, N0JK writes from Wichita, Kansas that he has been enjoying the high K and A indices on 6 meters. He reports that on November 3 and 5 there were strong F2 openings on 6 meters from most of the United States to the Caribbean and South America. On November 3 when John was mobile he worked TI5KD, J3/K6MYC and 8R1RPN, and K5CM in Oklahoma worked 3XY7C. On November 5 Jon was again mobile and worked VP2MJD, and W0EKT in Kansas worked ZD7MY.
Sunspot numbers for November 7 through 13 were 259, 252, 174, 219, 197, 155, and 182, with a mean of 205.4. 10.7 cm flux was 189.8, 189, 190.6, 191.4, 184.7, 178.2, and 182.4, with a mean of 186.6. Estimated planetary A indices were 14, 8, 9, 15, 12, 14, and 12, with a mean of 12.