ZCZC AP33
QST de W1AW
Propagation Forecast Bulletin 33 ARLP033
From Tad Cook, K7VVV
Seattle, WA August 14, 1998
To all radio amateurs
SB PROP ARL ARLP033
ARLP033 Propagation de K7VVV
Solar activity was up again last week in a big way. Average sunspot numbers were up by 42 points and average solar flux was up over 32 points. The highest solar flux was on August 9 when it was 154.1. The last time the flux was this high was in early 1993.
Over the next few days, Friday through Sunday, look for solar flux to decline to 140, 135, and 130. Solar flux should go under 120 around August 20 and down to 110 around August 22, then increase to over 150 again after the beginning of September. The planetary A index was very high at 69 on August 12, and we should see high A index values indicating geomagnetic disturbances around August 19 and 20.
There is more good news concerning the SOHO satellite, which is used to observe the sun. The satellite has now recovered to the point that it is sending out some data, such as temperature readings.
With solar flux over 150 and the season changing soon to Fall, strong 10 meter openings cannot be too far away. 15 meters should be stronger as well, now that the solar cycle seems to be moving up again.
Sunspot Numbers for August 6 through 12 were 122, 127, 121, 155, 136, 144 and 137 with a mean of 134.6. 10.7 cm flux was 138.3, 145, 146.8, 154.1, 149.2, 150.1 and 147, with a mean of 147.2, and estimated planetary A indices were 69, 28, 12, 4, 14, 9, and 10, with a mean of 20.9.