QST de W1AW
Propagation Forecast Bulletin 2 ARLP002
From Tad Cook, K7VVV
Seattle, WA January 10, 2003
To all radio amateurs
SB PROP ARL ARLP002
ARLP002 Propagation de K7VVV
After last week's big drop in activity, sunspots are back. The average sunspot number for this week was over twice what it was last week, and average daily solar flux was up over 32 points. Solar flux is expected to rise over the next few days, to 190 on Saturday, 195 on Sunday, and peaking on Monday around 200. But helioseismic images show no major spots on the sun's far side.
Right now we are inside a weak solar wind, and geomagnetic indices have been quiet since last Friday and Saturday. The planetary A index has been in the single digits, but is expected to rise slightly to 15 on Friday, and then drop back again.
The recent variation in solar activity shows that there is still life in this sunspot cycle, although over time we should expect a downward trend. We have passed the longest night of the year, and this is a good season for low band work on 160 and 80 meters, particularly when K and A index values are low.
As the days get longer, higher bands will improve as we head toward the spring equinox.
Sunspot numbers for January 2 through 8 were 74, 108, 117, 128, 141, 199, and 198, with a mean of 137.9. 10.7 cm flux was 118.3, 137.6, 143, 148.1, 162.1, 163.2, and 173.7, with a mean of 149.4. Estimated planetary A indices were 8, 13, 13, 9, 7, 9 and 7, with a mean of 9.4.