Each of the average solar
and geomagnetic indices rose last week (April 20-26) over the previous seven
days.
Average daily sunspot number rose from
8.6 to 35.7, and solar flux rose from 76.5 to 81.4.
Average daily planetary A index went
from 8 to 26.4, and average daily mid-latitude A index from 6.3 to 18.4.
The day with the most geomagnetic
activity was April 22 when the planetary A index was 54. One the same date,
Alaska’s College A index (near Fairbanks) was 86.
Predicted planetary A index is 8, 5 and
5 on April 28-30, then 14, 10, 8 and 10 on May 1-4, 15 on May 5-6, 8 on May 7-8,
5 on May 9-14, 8 and 15 on May 15-16, and then into a more active period at 30,
25, 45, 50 and 30 on May 17-21. Then 20 on May 22-24, then 15, 8, 5 and 20 on
May 25-28, 10 on May 29-31, 15 on June 1-2, 8 on June 3-4, and 5 on June 5-9.
Predicted solar flux values are 79 on
April 28-29, 78 on April 30 and May 1, 77 on May 2-4, 75 on May 5-14, 80 on May
15-18, 85 on May 19-24, 80 on May 25-28 and 75 on May 29 to June 10.
OK1HH sent us this geomagnetic activity
forecast for the period April 28 til May 24, 2017.
Geomagnetic field will be:
Quiet on May 9-10, 12-13
Mostly quiet on April 30, May 7
Quiet to unsettled April 29, May 2, 4,
14, 21-24
Quiet to active on April
28, May 1, 3, 8, 11, 15-16, 19
Active
to disturbed on May (5-6,) 17-18, 20
Amplifications of the solar wind from
coronal holes are expected on April 28, May (1-5,) 6-8, (9-11,) 18-22