ZCZC AP23
QST de W1AW
Propagation Forecast Bulletin 23 ARLP023
From Tad Cook, K7VVV
Seattle, WA June 5, 1998
To all radio amateurs
SB PROP ARL ARLP023
ARLP023 Propagation de K7VVV
Solar activity was up over the past week. Sunspot numbers averaged 16 points higher than the previous week and solar flux was up by almost 9 points. The average solar flux for May was 106.7, which followed 108.3 for April, 109.2 for March, 93.3 for February and 93.4 for January. Average flux values jumped from February to March, and have remained at about the same level since then. The outlook for June calls for an average solar flux possibly 10 points higher than May.
Over Friday through Sunday this week the predicted solar flux is 113, 114 and 112, with the Planetary A index around 14, 12 and 10. Solar flux is predicted to rise above 115 around June 11, and peak around 120 from June 16-19. It may fall to 110 by June 27, and unsettled geomagnetic conditions may return around June 8, 17, and 19-21.
With a rising solar flux and longer days, look for improved 15 meter conditions during daylight hours.
On the VHF front, N7DB reports good six meter openings recently, with regular contacts between the Pacific Northwest and the rest of the United States, with propagation across the continent nearly every day. Reports were also received concerning six meter contacts between Europe and the Caribbean.
NASA reported this week that two comets were observed plunging into the sun, followed by a mass ejection of solar gas. The solar event was thought not to be related to the comets passing into the sun.
Check http://umbra.nascom.nasa.gov/comets/SOHO_sungrazers.html on the web for pictures.
Sunspot Numbers for May 28 through June 3 were 47, 44, 62, 62, 59, 71 and 65 with a mean of 58.6. 10.7 cm flux was 98.4, 95, 96.1, 94.2, 100.1, 104.7 and 113.1, with a mean of 100.2, and estimated planetary A indices were 7, 19, 25, 7, 6, 7, and 12, with a mean of 11.9.