ZCZC AP49
QST de W1AW
Propagation Forecast Bulletin 49 ARLP049
From Tad Cook, K7VVV
Seattle, WA December 3, 1999
To all radio amateurs
SB PROP ARL ARLP049
ARLP049 Propagation de K7VVV
There was an error in the listing of sunspot numbers in last week's Propagation Forecast bulletin ARLP048. For November 24 the sunspot number was 157 instead of 109. This brought the average sunspot number for that week up to 192.3 instead of 185.4 as listed. Average sunspot numbers for the past week were down to 142.4.
Unfortunately, the usual source for the solar flux values resolved to .1 did not have the numbers available this week, so that data will be delayed until the next bulletin.
Sunspot numbers for November 25 through December 1 were 147, 143, 187, 173, 101, 127 and 119 with a mean of 185.4. Estimated planetary A indices for that same period were 18, 4, 3, 7, 4, 8 and 4, with a mean of 6.9. So while sunspot numbers were down, so was geomagnetic activity.
Solar activity is expected to rise over the next few days, with predicted solar flux for Friday through Sunday at 170, 180 and 190 and planetary A index at 5, 15 and 20. This does not look especially good for the 160 Meter contest this weekend.
Solar flux should peak around 230 by December 9, then drop below 200 after December 18.
Next week's bulletin should have a listing for all recent solar flux numbers.