A single small sunspot appeared on July 21, then disappeared. Before that, no sunspots appeared since June 26. The daily sunspot number on July 21 was 11, which is the minimum non-zero sunspot number.
Because there were no sunspots over the previous week, average daily sunspot numbers increased from 0 to 1.6, while average daily solar flux for the week declined from 71.8 to 68.4.
Average daily planetary A index changed from 6.4 to 8.1, and average daily mid-latitude A index (measured in Virginia) increased from 6.1 to 8.
Predicted solar flux is much lower than recently expected. Expected flux values (based on the July 26 prediction) are 66 on July 27 through August 2, 67 on August 3, 68 on August 4-10, 70 on August 11-18, 68 on August 19 through September 6, and 70 on September 7-9.
Predicted planetary A index is 5 on July 27-31, 18 and 8 August 1-2, 5 on August 3-11, 8 on August 12-13, 5 on August 14-15, then 7, 12, 5, 10, 25 and 15 on August 16-21, then 10 on August 22-23, 8 on August 24-25, 5 on August 26 through September 7, and 8 on September 8-9.
F.K. Janda, OK1HH, sends us this geomagnetic activity forecast for the period July 27 to August 22, 2018.
"Geomagnetic field will be:
Quiet on July 28-30, August 5, 11, 15
Quiet to unsettled on July 27, 31, August 10, 14, 16
Quiet to active on August 1, 6-9, 12, 19
Unsettled to active on August 3-4, 17, 20, 22
Active to disturbed on August 2, (13, 18,) 21
Solar wind will intensify on July (30-31) and August (16-19,) 20-22
- Parenthesis means lower probability of activity enhancement.
- Configuration of active areas in the Sun is changed, which temporarily reduces the reliability of predictions."
The latest from D. Skov, including her latest video:
“Surprisingly, our Sun continues to stay busy-- perhaps it missed the solar minimum memo? The latest blast of fast solar wind hitting Earth this week has already caused us to reach active conditions and we have a few more days under its influence before things calm back down. Although not at storm level, aurora over the past few days has been reported as far south as Germany in Europe and as far south as Michigan in the USA. Special thanks to Cornelius B and Martin D for these insider field reports!
“Even though we are getting auroral propagation with this storm on Earth's night side, sustained communication via amateur radio continues to suffer on Earth's dayside. We will have to wait nearly another week for a new bright region to rotate into view and boost the solar flux. We might see radio propagation improve slightly at the beginning of next week. At least GPS/GNSS users should continue to enjoy decent reception on Earth's dayside.
“Finally, I want to personally say THANKS for all the wonderful feedback I have gotten on my Patreon rewards tiers. I have been slammed preparing for a trip to Belgium this week and I still have some emails to write in response to your insightful suggestions and encouraging comments. So, if you haven't yet received a response from me, it is coming! By the way, next week I will be doing my forecast remotely. This means I must leave my production camera behind and go ‘low-tech.’ It’s always an adventure!
Click here for her video: https://youtu.be/K_o0TrAhRio
Jeff N8II in West Virginia wrote on July 24: "It has been a thrilling and bit exhausting last 3 days with 10-meter multi-hop sporadic E openings to Europe late Saturday morning, the 21st, and both morning and late afternoon/evening Sunday and Monday! I can’t remember such consistent European openings on Es any year and the odds are even more against it being a month after the summer solstice. I got to the radio late Saturday morning past 1500Z and I suspect the band had been open to Europe for a while already. Over less than 2 hours, I worked 23 Europeans and two stations in Africa. Most of the Europeans were in Mediterranean area countries such as Spain, France, and Italy. I also worked three stations in Germany, England, and the Czech Republic. Besides those contacts, I heard over 10 Spanish stations working each other in a contest on CW. I worked the following new DXCC band slots, IS0 in Sardinia, S01WS in Western Sahara, and probably 7V5D Algeria (weak). In the evening, I made six double-hop contacts with California, and several single hops into Texas and Missouri.
“Sunday, I was on earlier probably about the time the band was opening. There were at least two Spanish stations still working their contest and EA4URE gave me a signal report. I made seven European contacts, most with Germany and most signals were weak. I also found LZ2HR on CW in Bulgaria with a S7 signal for a new band slot. I also worked PJ2Y in Curacao, probably via Es. By 2112Z, the band was open again and I was working Italy, Spain, Switzerland, Hungary (HA9RT loud), and new band slots with Z68M Kosovo, and 9A2EU Croatia. I now have worked Kosovo, our newest DXCC entity, on all bands from 80 through 10 meters on CW, and four bands on SSB this year. I also worked Lauro, IK4GRO (loud), in Italy, as well as Tonno, ES5TV, in Estonia (quite a surprise) – both on SSB.
“Today, Monday, I made it to the radio at 1350Z and notice that there was a good European to European opening and, later, and opening from Europe to the Middle East. After a CW contact with England and a hello to Ian, MM0TFU, who always seems to be there when there is transatlantic Es, I started CQing and had a run of 16 stations from Northern Ireland, England, Wales, Scotland, Austria, Italy, France, and Germany. Then it was off to mostly search for DX on CW, working HB0/PC5A in Liechtenstein, and HA9RT in Hungary (loud as usual). But by far the most amazing event was hearing HZ1TT in Saudi Arabia running European stations, about 1/3 of which I could hear! I didn’t contact HZ1TT, (I have worked 7Z1SJ in past years), but it was amazing to hear his S1-4 solid copy signal for over 10 minutes. In fact, this was a first for me to hear Es into the Arabian Peninsula on 10 meters. At 1946Z, I returned to work Tony, T77C, in San Marino (a new band slot). On SSB, I worked stations in France, Italy (some over S9), Germany, Portugal, Austria, and Spain. At around 21Z on CW, I found E79D in Bosnia and CT3MD in Madeira Islands (S9) for new band slots."
When asked about six meters, on July 24 he wrote: "Oh, yes, quite a few openings to Europe, Texas and the Midwest. When I heard HZ1TT, there was a 9K2 working Europe on 6 meters. Most of my 6-meter DX is worked via FT8 on 50313 kHz, which allows decoding about 18-20 dB BELOW the noise level. There is halfway decent 10-meter SSB and CW activity also when 6 meters is open. I have not worked Europe since Monday on 10 meters, but the reports of Es were very minimal on Wednesday."
For more information concerning radio propagation, see the ARRL Technical Information Service at http://arrl.org/propagation-of-rf-signals. For an explanation of numbers used in this bulletin, see http://arrl.org/the-sun-the-earth-the-ionosphere.
An archive of past propagation bulletins is at http://arrl.org/w1aw-bulletins-archive-propagation. More good information and tutorials on propagation are at http://k9la.us/.
Monthly propagation charts between four USA regions and twelve overseas locations are at http://arrl.org/propagation.
Instructions for starting or ending email distribution of ARRL bulletins are at http://arrl.org/bulletins.
Sunspot numbers for July 19 through 25, 2018 were 0, 0, 11, 0, 0, 0, and 0, with a mean of 1.6. 10.7 cm flux was 70.5, 70.5, 70, 68.2, 67, 66.9, and 65.8, with a mean of 68.4. Estimated planetary A indices were 4, 7, 11, 5, 4, 17, and 9, with a mean of 8.1. Estimated mid-latitude A indices were 4, 7, 10, 5, 4, 16, and 10, with a mean of 8.