QST de W1AW
Propagation Forecast Bulletin 44 ARLP044
From Tad Cook, K7VVV
Seattle, WA October 29, 1999
To all radio amateurs
SB PROP ARL ARLP044
ARLP044 Propagation de K7VVV
Solar flux and sunspot number averages were down a little this week, although the numbers were starting to spike up again around Wednesday. Solar flux reached 197.3, and sunspot numbers were up to 200. Too bad this was accompanied by high geomagnetic activity. The planetary A index was 87 on Friday, with K indices up to 8. This was a raging storm.
There has been a lot of anticipation for the CQ Worldwide DX Phone Contest this weekend, and conditions could be a bit unsettled. The solar flux is expected to decrease over the next few days, with Friday through Sunday values at 175, 165 and 160. There is probably more interest in predicted geomagnetic values, since a geomagnetic storm is not much fun in an HF contest. The Fredericksburg middle latitude A index, which is close to the Boulder A index heard on WWV, is predicted to be 20, 15 and 15, for Friday through Sunday. The planetary A index is predicted to be 20, 20 and 15 for the same period.
After the weekend, solar flux is expected to bottom out around 135 early next week, then rise again to 200 a week later. The period around November 6-10 looks stormy, with A indices as high as 25.
K7CAR wrote to relate some unusual conditions on 10 meters on October 21. He experienced a lot of auroral propagation, and in addition to hearing distant stations quite well, he heard ones that were less than 100 miles away quite strong also. He has some nice pictures of his antennas at http://www.zing.com/cgi-bin/album.cgi?album_id=4294860361.
Sunspot numbers for October 21 through 27 were 154, 153, 114, 130, 179, 200 and 193 with a mean of 160.4. 10.7 cm flux was 158.5, 160.3, 164.5, 158.8, 179.2, 189.4 and 197.3, with a mean of 172.7, and estimated planetary A indices were 15, 87, 26, 23, 18, 9 and 17, with a mean of 27.9.
The path projection for this week is for the contest, and from the center of the United States.