venerdì 19 luglio 2019

The K7RA Solar Update

Very low solar activity continues. Over the past week, average daily solar flux changed insignificantly from 67.1 to 67. There were no sunspots.

Average daily planetary A index changed from 8.4 to 5.9, while mid-latitude A index changed from 8.6 to 6.7. Conditions remain quiet.

Predicted solar flux is 68 on July 19-26, and 67 on July 27 to September 1.

Predicted planetary A index is 5 on July 19-22, 8 on July 23, 5 on July 24-27, 8 on July 28, 5 on July 29 through August 3, then 8, 15, 15 and 8 on August 4-7, 5 on August 8-10, then 10, 12 and 8 on August 11-13, 5 on August 14-23, 8 on August 24, 5 on August 25-30, then 8 and 15 on August 31 through September 1.

Geomagnetic activity forecast for the period July 19 until August 14, 2019 from F.K. Janda, OK1HH of the Czech Propagation Interest Group.

Geomagnetic field will be:
Quiet on July 19, 24-25, August 2-3, 8, 13-14
Quiet to unsettled on July 26-27, 29-31, August 1, 4, 9
Quiet to active on July 20-23, August 7, 10-12
Unsettled to active on July 28, August 5-6
No active to disturbed days are predicted.

Solar wind will intensify on August (2-3,) 7-8, (9-14)

Parenthesis means lower probability of activity enhancement.

On July 17  reported a coronal hole spewing a stream of solar wind, with arrival expected to cause minor geomagnetic upset around July 19-20.

They also reported that so far in this calendar year 64% of all days were without sunspots. Last year the total number of spotless days was 61%, 28% in 2017, 9% in 2016, and zero days were spotless in 2011-2015, except for 2 days in 2011 and 1 day in 2014.

On Saturday morning, July 13, Charles Brown, N4SO, of Grand Bay, Alabama reported, “I was on 24.915 MHz using the FT8 digital mode. My output power was 15 W and I was testing a new antenna.

“I worked K1HZ (Texas), W6SR (California), K0TW (Arizona), K0COL (Colorado), KF7F (Utah),
TG9AKH (Guatemala), and K0JJ (Oregon). I saw other DX, but no contacts.

“The 12 meter band opened today (Saturday) with only three stations calling CQ: W2SKI (Virginia), XE2YWB (Zacatecas, NW of Mexico City) and VE2GCE (Quebec).”

Richard Zabrodski, VE6GK, wrote, “It has been almost 50 years since my first contact and I still love learning about and following the sunspot cycles.”

Tamitha Skov, WX6SWW, posted this video on July 12:

Also, on July 12, Joe Lewis, KD4SR, reported (in a message titled “Don’t forget Sporadic-E!”), “Yesterday I worked Puerto Rico, Haiti, Canada and many others from Central Florida on 6 meters with 100 W and FT8. Japan was worked by others.  Europe, Africa, and all over North and South America have been heard regularly on 6 almost. I am just using a G5RV and ground plane antennas.  Summer is Es season!”

Jeff Hartley, N8II, wrote, "The day before the IARU HF Championship, 10 meters opened fairly well to Europe; at around 2016Z I turned on the radio to find EA4ZK on 10 CW with a S6-8 signal and I made an easy contact. This was followed by CW contacts with Belgium, Germany, Oliver, France, Bulgaria, the Czech Republic, Italy, Aruba and  Barbados. I switched to SSB and worked EC1KR in Spain and F4FPG. The last European contact was with OK1CF at 2217Z.

“Chores prevented any activity in the contest on the 13th until 1910Z when I found EI7M, Ireland, on 10-meter CW. The band was also wide open to New England, New York and Florida. Thanks to the many IARU member headquarters stations being on all bands whenever open, I managed quite a few European contacts.

“On CW, The IARU HQ stations in France, England, and later Belgium, Poland, Czech Republic, and Slovenia were worked along with stations in Germany, Croatia, Belgium, Hungary, and England.

“On SSB at 1932Z I quickly worked six HQ stations in Croatia, France, Serbia, Italy, and Switzerland, and then later adding Germany. It was disappointing that there was almost no non-HQ activity on SSB.

“The propagation highlight was hearing 4Z7ZZ in Israel with a strong signal calling IO8HQ in Italy; that is huge number of Sporadic E hops! PX2A in Brazil was also logged at 1916Z.

“On 15 meters, the European stations were more numerous as were many USA stations in all parts of the country. There was some propagation to all of South America, and Hawaii was good copy via mostly Sporadic E, I would guess.

“By the time I managed to get some time on 20 meters, the E-skip to Europe was largely gone, but many European HQ stations were still active with good signals. Late in the evening past 0300Z, I was called by ZL2BAQ and ZL4NR in New Zealand, and VK4SP in Queensland, Australia on 20-meter SSB.

“On CW, at around 0300Z, the band was open to ITU zones across Asiatic Russia from Sakhalin Island to the Ural mountains, but activity was low.

“Forty meters was open well to the USA, Canada, and Europe from sunset through 0300Z, but the HQ station count was lower than expected.

“NU1AW, the IARU HQ station in Newington, Connecticut, was very active on all bands. It was easy making CW and SSB contacts 10 and 15 meters, and CW on 20 and 40 meters."

Here is the very latest video from Dr. Tamitha Skov, WX6SWW:

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Sunspot numbers for July 11 through 17, 2019 were 0, 0, 0, 0, 0, 0, and 0, with a mean of 0. 10.7 cm flux was 67.1, 66.8, 66, 67.2, 67.1, 67.2, and 67.8, with a mean of 67. Estimated planetary A indices were 8, 5, 6, 5, 7, 4, and 6, with a mean of 5.9. Middle latitude A index was 9, 5, 6, 6, 8, 5, and 8, with a mean of 6.7.