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The K7RA Solar Update

04/03/2020

A new sunspot appeared on the last day in March and the first days of April, with daily sunspot numbers of 12, 13 and 12. Total sunspot area increased on each day from 10 to 20 to 30 millionths of a solar hemisphere.

Fortunately, this was a Cycle 25 spot, according to the magnetic signature.

Prior to this no sunspots were seen since earlier in March, when daily sunspot numbers were 13 and 12 on March 8-9.

Average daily solar flux this week (March 26 through April 1) declined from 71.1 to 69.4. Average daily geomagnetic indicators were identical to the previous week, with planetary A index at 7.7 and middle latitude A index at 5.9.

Predicted solar flux for the next 45 days is 70 on April 3-22, then 68 on April 23 to May 7, and 70 on May 8-17.

Predicted planetary A index is 8 on April 3, 5 on April 4-14, 10 on April 15, 8 on April 16-19, 5 on April 20-25, 12 on April 26-27, 8 on April 28-29, 5 on April 30 through May 11, 10 on May 12, 8 on May 13-16 and 5 on May 17.

Geomagnetic activity forecast for the period April 3-29, 2020 from OK1HH.

Geomagnetic field will be
quiet on: April 6-7, 10, 20-21
quiet to unsettled on: April 3-5, 11-13, 24, 28-29
quiet to active on: April (8-9, 25)
unsettled to active on: (April 14-19, 22-23,) 26-27
active to disturbed: none predicted

Solar wind will intensify on April 9, 12-13, (15-16,) 17-19, (20,) 26-28

- Parenthesis means lower probability of activity enhancement.
- The predictability of changes remains lower as there are no indications.


Chip, K7JA, reports, "The late afternoon of March 31, 2020 brought a 6-meter opening to the southern half of California, as well as states to the east. Here in DM03, south of Los Angeles, I worked Dale, CE2SV, on FT8 at 2325 UTC, followed by CE3BN, XQ3MCC, and XQ3SK/4. I worked CE2SV on CW at 0002 UTC (1 April), and several other CE and LU stations were heard but not worked, along with HC2GR. Flags from PSKReporter indicate that I was heard by a total of seven CE stations, plus LU9FVS.

“Because we are so far north (geomagnetically), I suspect this may well have been an E-to-TEP path. Stations as far north as the San Francisco Bay area got in on the opening, as well.

“There was no activity on the afternoon of April 1, but you can bet the entire West Coast is watching.

“I run about 180 W from a Kenwood TS-990 transceiver to a 7-element LFA (Loop Fed Array) about 72 feet high."

Jon Jones, N0JK, commented. “Remarkable results with a solar flux of only 69.”

Here is some information about the LFA Yagi:
https://www.innovantennas.com/en/lfa-benefits

N0JK also reported, "Sporadic-E propagation appeared on 50 MHz on  the afternoon of March 28 from Kansas to Florida. I worked NØRW in grid EL87 on 6-meter FT8 at 2242z. I decoded WB4JPG (EM71) but no contact.

“KFØM in Wichita, Kansas (EM17) also made several 6-meter Es contacts with Florida stations including K3VN. He copied W5LDA (EM15) working CO3JR (EL83) at 2355z on FT8.

“Sporadic-E is rare in March. The month of March has the lowest occurrence of sporadic-E of any month for the northern hemisphere."

WB5AGZ reported from Stillwater, Oklahoma: "I have been hearing what I believe to be Sporadic E almost every afternoon since about last Sunday, March 29. It is weak but certainly present with long slow fades.

“The first evidence was a few seconds during the afternoon of March 29 with a repeater system in North Carolina. The opening was never long enough to pick out a complete call sign, but one could hear parts of the repeater's voice ID.

“The exact time is not known because this is a recording made over many hours from a scanner connected to a computer running software that makes a VOX-style sound recording without individual time stamps.

“It is now Thursday, April 2, and a playback from Wednesday picked up a long conversation between two amateurs using the KQ2H system in the New York City area.

“Signals were just strong enough to mostly copy with very long periods in which it sounded like a system in a town almost out of range coming via ground wave propagation. The signal would then fade and return.

“A recorded female voice announced the time as 7:15, which is as close to a time stamp as I have. In the Central Daylight time zone, this would have been 18:15 or 23:15 UTC. My antenna is a discone about 50 feet above ground, feeding a Uniden BCD996XT scanner monitoring 6 and 10 meters.”


Space.com offers a solar cycle observation:
https://www.space.com/new-solar-cycle-starting-any-day-now.html

Ken, N4SO, reports from Alabama, "This late night propagation is now setting a pattern.

Mode: FT8, Frequency 21.074 MHZ

March 31    12:27 AM local start time, ending 12:30 AM local
(the four digits on the left are UTC)

The stations are in Australia and New Zealand

052730 -14  0.2 1196 ~  VR2XYL ZM3SSB RE66
052800 -16  0.2 1196 ~  VR2XYL ZM3SSB RE66
052830 -16  0.2 1195 ~  VR2XYL ZM3SSB RE66
053000 -16  0.2 1196 ~  VR2XYL ZM3SSB RE66
The radio is often left on to monitor the frequency 21.074 MHz”

You can use PSKReporter to see what Ken is currently hearing. Go to https://www.pskreporter.info/pskmap.html and select 15 meters and signals received by N4SO using FT8.

KA3JAW monitors 11 meters and made this report of a sporadic-E opening: "On Tuesday, March 31, 2020, eleven days after the passing of the spring equinox (March 20), unexpected visitors waved their hands on the 11 meter band for attention for six straight hours.

“At 4:37 pm local (ET) Mid-Atlantic states noticed sporadic-e signals originating from the southeastern states of Louisiana, Mississippi, Alabama, Florida, and Georgia.

“One hour later, I heard signals from Tennessee, Arkansas, and Texas. By the 9 o’clock hour, the propagation was slowly degenerating and by 10:30, it had disappeared.

The last time an event like this took place, was on February 24 from 9:58 am to 12:49 pm local time (ET)."

Thanks to Don Wright, AA2F, for catching an error in the earlier version of this bulletin in the ARRL Letter, in which I neglected to update the solar flux and sunspot number averages from last week’s numbers. One thing that contributed to the confusion was the fact that the averages for the geomagnetic indices were exactly the same as the previous week’s data.

If you would like to make a comment or have a tip for our readers, email the author at 
k7ra@arrl.net.

For more information, see http://www.arrl.org/propagation and 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.

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 March 26 through April 1, 2020 were 0, 0, 0, 0, 0, 12, and 13, with a mean of 3.6. 10.7 cm flux was 70.2, 69.4, 69.2, 68.8, 69.3, 69.9, and 69.2, with a mean of 69.4. Estimated planetary A indices were 5, 5, 5, 7, 11, 15, and 6, with a mean of 7.7. Middle latitude A index was 5, 4, 4, 6, 8, 10, and 4, with a mean of 5.9.

 



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