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The K7RA Solar Update


On Wednesday, June 20 reported the sudden emergence of sunspot AR2715. The sunspot number on that day shot up to 54, and it was 53 the next day. Average daily sunspot number for the reporting week (June 14-20) was 25.7, up from 4 the previous week. Average daily solar flux rose from 69.4 to 74. Solar flux was 82.1 on June 20.

We have not seen numbers such as this since last September. This is good news just before ARRL Field Day, assuming the activity does not produce any geomagnetic disturbance.

Predicted solar flux is 82 on June 22, 80 on June 23-24, 78 on June 25-28, 75 and 70 on June 29-30, 68 on July 1-6, 70 on July 7, 72 on July 8-13, 74 and 72 on July 14-15, 74 on July 16-20, 70 on July 21-27, 68 on July 28 through August 2, and 72 on August 3-5.

Predicted planetary A index is 5 on June 22-23, then 12, 8, 5, 8, 20, 15 and 10 on June 24-30, 5 on July 1-14, 8 on July 15-16, 5 on July 17-20, 8 on July 21-22, then 5, 15, 28, 18 and 10 on July 23-27, and 5 on July 28 through August 5.

We saw some heightened geomagnetic activity on Monday, June 18 UTC when the planetary K index rose to 5, and later in the day Alaska’s College K index hit 6 over two of the eight 3-hour periods for the day. College A index was 33. 

Jeff Hartley, N8II of Shepherdstown West Virginia sent this report yesterday, June 21: "Today we are finally taking a breather from widespread sporadic E openings to many different areas. The best 10-mter opening I have worked so far was on June 4 when I worked 72 European stations on SSB with best DX into Poland, Slovak Republic, and Greece (the most European stations ever worked by me in single Es opening). Quite a few were running 25 W or less and I worked all the UK countries except Jersey which was self-spotted. Incredible! 

“On the morning of June 17, I heard about 15 Italian stations on 10-meter CW and SSB working the Italian 10-meter contest; none would stop long enough to answer my calls. But, after returning from the W3LPL open house, I started making QSOs for the West Virginia QSO Party on 10-meter SSB and there was IT9ACN at 2207Z calling CQ in his contest and he was thrilled to work me; he and his Sicilian friend IT9BUN were both about S8 with QSB. I went on to work another IT9, IK7, and MM0TFU (weak) in Scotland, along with 19 USA stations to the west and south. After moving to 15 meters, a station from northern Spain called in and quite a few European stations were worked in the 2300 and 2400Z hours on 20-meter SSB along with many Es QSOs into all W4s (except VA/NC), OH, MI, all W9s, all W5s, and NY plus all New England states.

“The party continued on 10-meter SSB on the June 17 working KW2W in Vermont at 1309Z and then, on 15-meter CW, HV0A in the Vatican (my first Vatican contact in over 1-1/2 years) via probable Es. Then, it was back to 10-meter SSB double hop Es at 2333Z with Steve, WB2WIK, in Los Angeles also working two other southern California stations. I also contacted stations in Florida, Kansas, Missouri, Illinois, Alabama, and Mississippi. 

“On the June 18, starting at 2039Z on 10-meter CW, I found and worked F5NBX in France, M0BKL in England, and IK1ZOC in Italy. Then, starting 2215Z on 10-meter SSB, I worked WP4PPV in Puerto Rico, as well as stations in Maine and Florida.

“On June 19, starting 2024Z on 10-meter CW, I found HB9BKL in Switzerland, M0BKL again, and I was called by IU4FJI in Italy. Then, I switched to 10-meter SSB to work 2E0IQD in England and I5KAP in Florence, Italy. 

“June 20 featured very intense sporadic E for many hours, so I returned to 10-meter SSB at 0123Z, working K7CAR at a state park in Utah, and many more stations in Utah, Colorado, Arizona, Kentucky, Michigan and elsewhere. Almost all day long during the daytime into late evening there was widespread Es, but I was too busy until 2350Z to operate. That’s when I worked Minnesota, New York (a station in rare grid FN13), VE3TM in FN25, and a Missouri station on 6 meters. Then it was down to 10-meter SSB again to work many other stations before calling it a day at 0120Z.”

Mike Treister, W9NY, of Chicago wrote: "It is interesting to hear about the increased sunspots. I have heard a lot of skip - few hundred miles - from all directions on 6 and 10 meters the past few days. Signals have been quite strong. It is nice to hear so many new hams being excited with their 10 and 6-meter contacts.”

Here is a new report from Dr. Skov:


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Sunspot numbers for June 14 to 20, 2018 were 16, 13, 13, 15, 28, 41, and 54, with a mean of 25.7. 10.7 cm flux was 72.4, 70.6, 70.5, 72.3, 73.7, 76.6, and 82.1, with a mean of 74. Estimated planetary A indices were 5, 4, 3, 5, 19, 6, and 5, with a mean of 6.7. Estimated mid-latitude A indices were 7, 6, 4, 7, 20, 6, and 7, with a mean of 8.1.