Register Account

Login Help


The K7RA Solar Update


After no sunspots over the entire month of February, sunspot group 2734 appeared on March 5. So far, the new sunspot numbers are 14, 17, and 14 on March 5-7. I believe this was the longest consecutive period (33 days) with no sunspots on this declining side of Cycle 24. The polarity of the new sunspot group identifies it as being from Cycle 24, not the upcoming Cycle 25.

Frank Donovan, W3LPL sent a link from the Royal Observatory in Belgium showing brief sunspot appearances on February 13 and 21:

But numbers from NOAA do not show these.

It is interesting to note that we are currently seeing the lowest sunspot activity since August 2008 during the last solar minimum, between Cycles 23 and 24.

Frank also sent this link, concerning spotless days:

And a newsletter:

Average daily sunspot numbers for the week increased from 0 to 4.4, compared to the previous seven days. Average daily solar flux was unchanged at 70.6.

Average daily planetary A index rose from 4.9 to 12.6, and average mid-latitude A index increased from 4 to 9.7. These geomagnetic indicators were higher due to effects of a solar wind stream on February 28 and March 1.

Predicted solar flux is 71 on March 8-12, and 70 on March 13 through April 21.

Predicted planetary A index is 12, 10 and 8 on March 8-10, 5 on March 11-13, 10 on March 14-15, 5 on March 16-25, then 12, 30, 28, 14, 8 and 10 on March 26-31, then 8, 5, 10, 15, 12, 12 and 8 on April 1-7, then 5 on April 8-15, 10 on April 16, and 5 on April 17-21.

In reference to the predicted planetary A index, here is the geomagnetic activity forecast for the period March 8 until April 6, 2019 from F.K. Janda, OK1HH.

Geomagnetic field will be:
Quiet on March 14-15, 23-24
Quiet to unsettled on March 9, 17-18, 22, 25
Quiet to active on March 8, 10-13, 19-21, 31, April 1-2
Unsettled to active on March 16, 26, 29-30
Active to disturbed on March 27-28

Solar wind will intensify on March (8-9,) 13-14, (15,) 21-22, 25-28, April 1, (2, 5)

Parenthesis means lower probability of activity enhancement.

Dr. Tamitha Skov, WX6SWW sent this: “We have been enjoying an unusual increase in activity over the past week. First, the Sun launched a solar storm that grazed Earth. Nice to see our solar minimum Sun can still launch storms every now and again! This solar storm enhanced a relatively weak period of fast solar wind and caused aurora to drop down to mid-latitudes, lasting for nearly two days. We haven't seen a storm that engaging since 2018!

“As if that wasn't enough fun, two new hot spots have emerged in Earth view alongside a third bright region that was already visible. Three active regions on the Earth-facing Sun? We haven't seen that since 2017!

“Additionally, the biggest and brightest of these hotspots has now grown into a "rogue" sunspot. This means it clearly shows an influence from the coming Solar Cycle 25! Although we cannot officially designate this region, numbered 2734, as a sunspot from the new cycle, its magnetic signature is very peculiar. Its magnetic poles sit one on top of the other instead of side by side. This is unusual and point to the region being a bit confused as to which cycle it belongs. I will be sure to report on it in more detail during my Solar Storm forecast that I'll finish late this week.

“As for the current forecast, expect solar flux to remain in the low to mid 70's due to the new active regions. This will give radio propagation a nice boost on Earth's day side. Also, as the solar storm continues to wane, GPS reception should continue to improve on Earth's night side and at high latitudes. However, satellite operators and users should be aware of an increase in anomalies over the next few days due to the enhanced near-Earth radiation environment right now. This is especially true for those satellites in geosynchronous orbits (GEO) like Direct TV and SIRIUS-XM Radio. So if your satellite radio glitches while you're listening to your favorite song, you'll know why.”

See her latest video here:

In last week’s bulletin ARLP009 I expressed my confusion over the numbers in FT8 reports. Thanks to N6KW, N5UWY and others for clearing this up. Here is N6KW’s missive: “The FT8 QSO, left to right, is Zulu time, signal/noise ratio in dB, time deviation in seconds, audio frequency in the passband. So, JA4FKX's signal was 13 dB below the noise at the time of copy.”

N5UWY wrote: "That's a cut/paste from WSJT-X (K1JT's software package for all the modes he and his colleagues have developed). Fields are ‘UTC, signal strength in dB relative to the noise level in a 2500-Hz bandwidth, delta in seconds between received station's clock and UTC, the number of Hertz above the dial frequency, then the message from the other station Japan (or JA) is tacked on after the message by the software to indicate the DXCC entity by name or prefix.

"’343’ here means that JA4FKX was transmitting on 10136.343 kHz. Further, his clock was 0.3 s off UTC (according to the receiving station's clock which could be off itself!) and the JAs signal was 13 dB down from the noise level that the software was seeing at the receiver.

“I am totally an expert now on FT8. I started using it on January 28 and by February 27 or so, I had WAS on 30 m and FT8! Made about 350 QSOs. Got some DX, too. 30 meters is an interesting band and I'm glad I stuck it out there as I'd never really operated on the band before. I'm kidding - I am in no way an expert. I didn't even stay at a Holiday Inn.

“FT8 is kind of addicting, but it’s fun. I even worked an all-time new one on 30 meters - Reunion Island my second-best DX ever. I think I'm running about 50 W to a trap dipole at about 25 to 30 feet."

On March 6, Steve Sacco, NN4X, wrote: “Due to dreadful conditions, I seriously did not want to suffer through the ARRL DX contest last week, but I did want to play on the radio. I've only been on 12 meters since December 2018, so I have been making a point to check it frequently.

“Just to show that there is propagation, here's a selection of what I've worked from Florida recently.
VK3BDX Feb 28
LU, PY, YV, T31EU, YN, FY, EA8/DL9XJ, CE, CX, EA7DT, HK, HD8M (HC8) Mar 2, 3
CE0YHO Mar 3, T31EU Mar 2, 3, EA8AXT, EA8AKN, EA9ACD Mar 5

“So, the moral of the story is ‘Never Give Up Hope’".

On March 7 Steve wrote again: “FT8 is a fantastic tool for monitoring prop. It allowed me to document a fascinating but short 30-minute opening to Africa from Florida, resulting in RF being expended from my side, but no QSOs. My antenna: JK Antennas JK-WARC 121730 (3 elements on 17 meters) at 113 feet.
EA9AK 1502Z
5X2S  1516Z
Z81D  1530Z”

If you would like to make a comment or have a tip for our readers, email the author at,

For more information concerning radio propagation, see the ARRL Technical Information Service at For an explanation of numbers used in this bulletin, see

An archive of past propagation bulletins is at More good information and tutorials on propagation are at

Monthly propagation charts between four USA regions and twelve overseas locations are at

Instructions for starting or ending email distribution of ARRL bulletins are at

Sunspot numbers for February 28 through March 6, 2019 were 0, 0, 0, 0, 0, 14, and 17, with a mean of 4.4. 10.7 cm flux was 70.1, 69.9, 69.4, 69.5, 70.9, 72, and 72.5, with a mean of 70.6. Estimated planetary A indices were 26, 24, 12, 6, 7, 5, and 8, with a mean of 12.6. Estimated mid-latitude A indices were 17, 18, 9, 6, 7, 4, and 7, with a mean of 9.7.




Instragram     Facebook     Twitter     YouTube     LinkedIn