Tad "My Sun sets to rise again" Cook, K7RA, this week reports:
Recent days graced by sunspots were short lived. June 10-June 13 saw a single sunspot group, followed by two days with no spots then a week of spots from June 16-22. During that week, the sunspot number was 11 every day, the lowest non-zero sunspot number. The four days since have had no spots at all.
This weekend is ARRL Field Day, and while there are no sunspots, E skip (Sporadic E) is a possibility and conditions should be quiet, meaning no geomagnetic disturbance is expected.
Predicted planetary A index for June 27-July 3 is predicted at 10, 8, 5, 5, 5, 5 and 5. Geophysical Institute Prague expects unsettled conditions June 27-28, quiet to unsettled June 29 and quiet June 30 to July 3.
Sunspot numbers for June 19 through 25 were 11, 11, 11, 11, 0, 0 and 0 with a mean of 6.3. The 10.7 cm flux was 64.9, 65.2, 64.8, 65.4, 65.3, 65.8 and 65.9 with a mean of 65.3. Estimated planetary A indices were 6, 11, 5, 4, 3, 4 and 12 with a mean of 6.4. Estimated mid-latitude A indices were 5, 8, 4, 2, 2, 3 and 10 with a mean of 4.9.
For more information concerning radio propagation, visit the ARRL Technical Information Service Propagation page <http://www.arrl.org/tis/info/propagation.html>. To read this week's Solar Report in its entirety, check out the W1AW Propagation Bulletin page <http://www.arrl.org/w1aw/prop/>.
| Notes | This solar update is brought to you courtesy of the American Radio Relay League's ARRL Letter. |