Tad Cook, K7RA, Seattle, reports: Not much change in the numbers since
last week, but all indicators were lower. The average daily sunspot
number moved from 29.4 to 20.3, and average daily solar flux went from
74.6 to 73.6.
The average daily planetary A index dipped from 9.4 to 6.9, and the mid-latitude A index from 8.1 to 7.4.
Predicted solar flux is 72 on June 29-July 2; 70, 71, and 72 on July
3-5; 74 on July 6-7; 75 on July 8-14; 76 on July 15-16; 75 on July
17-19; 74 on July 20-22; 72 on July 23-24; 77 on July 25-28; 74, 73 and,
72 on July 29-31; 73 on August 1; 74 on August 2-3, and 75 on August
4-10.
The predicted planetary A index is 10 on June 29-30; 5 on July 1-12; 20,
12, and 10 on July 13-15; 5 on July 16-20; 10, 12, 10, and 5 on July
21-24; 10 on July 25-26; 5 on July 27-August 8, and 20, 12, and 10 on
August 9-11.
The ARRL website includes monthly propagation charts between four US regions and 12 overseas locations.
Sunspot numbers for June 22 through 28, 2017 were 23, 22, 28, 20, 19,
17, and 13, with a mean of 20.3. The 10.7-centimeter flux was 73.7,
73.7, 74.1, 73.7, 73.7, 74.1, and 72.1, with a mean of 73.6. Estimated
planetary A indices were 6, 5, 9, 11, 7, 5, and 5, with a mean of 6.9.
Estimated mid-latitude A indices were 8, 6, 8, 11, 9, 5, and 5, with a
mean of 7.4.
In Friday’s bulletin look for an updated forecast and reports from
readers, including 6-meter reports from Rich Zwirko, K1HTV, and Scott
Bidstrup, TI3/W7RI. Send me your reports or observations, especially on propagation during ARRL Field Day.
