QST de W1AW
Propagation Forecast Bulletin 1 ARLP001
From Tad Cook, K7VVV
Seattle, WA January 7, 2000
To all radio amateurs
SB PROP ARL ARLP001
ARLP001 Propagation de K7VVV
For the first propagation bulletin of the new year, we will review some of the solar numbers for 1999.
Currently we are moving toward the peak of solar cycle 23. Activity is not as high as we had hoped, and current projections place the broad peak of the cycle some time later this year.
We can see a broad progression of the current cycle by reviewing annual solar flux averages. The average daily solar flux in 1996, 1997 and 1998 was 70.8, 80.9 and 117.9, and for 1999 it was 153.7.
The average daily solar flux for the four quarters of this year were 136.7, 145, 157.6 and 175.2 for the quarter just ended. This indicates a steady upward trend. Monthly averages of daily flux values for September through December were 135.7, 164.8, 191.5 and 169.8.
So what does the short term outlook say? Projected solar flux for Friday through Sunday is 150, 155 and 160, and the projected planetary A index is 10, 8 and 12. Beyond the weekend it looks like quiet geomagnetic conditions for January 10-19, moderately unsettled around January 20 and 21, then quiet again until January 26 through the end of the month. The most active days should be around January 27 and 28 due to recurring coronal holes. Solar flux should rise until January 16 and 17, peaking around 205, the drop below 150 by January 25.
If you want to graph data from these bulletins, you should try WA4TTK's graphing program. The solar flux and sunspot database has just been updated, so it now covers 11 whole years, from January 1, 1989 to December 31, 1999. You can download the software and the data from http://edge.net/~scraig/sol.htm. Then starting with this bulletin and for every bulletin after this, you can use the WA4TTK freeware to import the data automatically from the bulletin text and display it graphically.
Sunspot numbers for December 30 through January 5 were 88, 91, 69, 69, 77, 102 and 100 with a mean of 85.1. 10.7 cm flux was 135.6, 130.1, 129.9, 132.9, 133.1, 134.7 and 136.5, with a mean of 133.3, and estimated planetary A indices were 8, 27, 27, 14, 13, 12 and 15, with a mean of 16.6.
Path projections for this weekend are to Japan for the JA International DX CW Contest.