ZCZC AP47
QST de W1AW
Propagation Forecast Bulletin 47 ARLP047
From Tad Cook, K7VVV
Seattle, WA November 22, 2000
To all radio amateurs
SB PROP ARL ARLP047
ARLP047 Propagation de K7VVV
This bulletin is written a day and a half earlier than usual because of the Thanksgiving holiday. For that reason, the projected solar flux and A indices expected for this weekend will not be quite as up to date as usual. Also, it is too early to include the sunspot number for Wednesday, the end of our normal reporting week, so next week's bulletin will have two week's worth of solar flux, sunspot numbers and planetary A indices.
Geomagnetic indices have been very quiet this week, with both the planetary and Boulder A indices in the single digits. The quietest day was Thursday, November 16, when the Boulder A index was one, and the Boulder K index was zero for most of the day. This indicates a very stable geomagnetic environment. The planetary A index was four on that day and on the next.
Solar flux has been rising after reaching a near term minimum on November 14. It was 173.7 on Monday, 185.4 on Tuesday, and today on Wednesday, the three daily readings were 192.4, 194.9 and 203.5. The noon reading of 194.9 is the official number.
The current projection has the 10.7 cm flux rising above 200 on Thanksgiving, peaking at 210 on Friday, then 205 on Saturday and 200 on Sunday through next Thursday. This looks good for the big DX contest this weekend, although generally the Maximum Usable Frequency is more dependent upon the average solar flux for the previous week or ten days rather than a value on the day of interest. The predicted planetary A index also looks good, which currently is projected to be ten for Thursday through Saturday, and twelve for Sunday and Monday.
There was a full-halo coronal mass ejection last week on November 16, but it was on the back side of the sun, projecting the energy away from earth. It was only partially seen. The region that produced that activity will be rotating into view sometime soon, but not soon enough to affect the contest weekend.
N0AX pointed out that last week's bulletin mention's something called a solar ''flair''. Of course, your author was only demonstrating a flair for erroneous homonyms. That thing coming out of the sun is still a flare, no matter what is written here. After re-reading the above three lines, your author realized that he actually referred to himself as your ''other'', so that homonym problem is only getting worse with age. Your author still thinks of himself as a young ham, but that is because he was first licensed at age 12. Never mind that this was over 35 years ago. Senior moments seem to be increasing weekly. Happy Thanksgiving to all.