QST de W1AW
Propagation Forecast Bulletin 15 ARLP015
From Tad Cook, KT7H
Seattle, WA April 12, 1996
To all radio amateurs
SB PROP ARL ARLP015
ARLP015 Propagation de KT7H
The Sun is spotless. There have been no visible sunspots for six of the past seven days, and the average solar flux is a point lower than last week. As mentioned in ARLP014, we should be at the beginning of the sunspot minimum, and the solar flux minimum should occur later this year.
The last propagation bulletin had a confusing error which mentioned both 158 and 192 as the solar flux for April, 1999. Actually 192 is the projected average solar flux for April, 2000.
This month the geomagnetic field should stay stable, but April 17 and 18 could bring a recurring moderate disturbance. The solar flux should rise above 70 by April 18 through 24, and go back below 70 after May 3.
Sunspot Numbers for April 4 through 10 were 11, 0, 0, 0, 0, 0 and 0, with a mean of 1.6. 10.7 cm flux was 70.2, 69.9, 68.7, 68.4, 68.4, 69 and 68.8, with a mean of 69.1.