16 March, 2019
Sunspots reemerged for 8 days on March 5-12.
Average daily sunspot numbers rose from 4.4 in last week's bulletin to
9.9 this week (March 7-13). Average daily solar flux barely changed,
from 70.6 to 70.9. Average planetary A index declined from 12.6 to 5.1,
and average middle latitude A index from 9.7 to 3.9.
The Vernal Equinox will occur next Wednesday, March
20 when the southern and northern hemispheres will be bathed in equal
amounts of solar radiation.
Predicted solar flux is 70 on March 15-17, 68 on
March 18-22, 69 on March 23-28, 70 on March 29, 71 on March 30 through
April 8, 70 on April 9, 69 on April 10-24, 70 on April 25 and 71 on
April 26-28.
Predicted planetary A index is 12, 8 and 8 on March
15-17, 5 on March 18-19, 10 on March 20, 5 on March 21-25, then 12, 30,
28, 14 and 8 on March 26-30, 5 on March 31 through April 1, 8 on April
2-3, 5 on April 4-9, then 12, 10 and 8 on April 10-12, 5 on April 13-15,
10 on April 16, 5 on April 17-21, then 10, 26, 24, 12 and 8 on April
22-26 and 5 on April 27-28.
Geomagnetic activity forecast for the period March 15 to April 13, 2019 from F.K. Janda, OK1HH.
"Geomagnetic field will be:
Quiet on March 22-24, 31, April 4-9. 13
Quiet to unsettled on March 16-18, 25, April 1-3,
11-12 Quiet to active on March 19-21, April 10 Unsettled to active on
March 15, 26, 29-30 Active to disturbed on March 27-28
"Solar wind will intensify on March (15,) 21-22, 25-28, April 1, (2, 5)
"Parenthesis means lower probability of activity enhancement."
Australia's Space Weather Services issued a
geomagnetic disturbance warning at 0003 UTC on March 15: "Increased
geomagnetic activity expected due to coronal hole high speed wind stream
on March 15-16, 2019.
"15 March: Unsettled to Active, possible Minor Storm periods for High latitudes. 16 March: Quiet to Unsettled"
Jim DeYoung, N8OQ sent this interesting question on March 13:
"I have been wondering about the fact the north
magnetic pole has been shifting towards Russia significantly and
therefore are there any expected resultant significant shifts in the
auroral oval that would affect propagation to/from North America or to
Asia?
"The reason I ask is I made probably my best QSO of
all time a few weeks ago during the CQ 160m Phone contest. I always run
QRP for that contest as a good test of my operating skills (ears),
noise levels, rigs, and most importantly my antenna. I have used for
many years a 93-meter horizontal loop fed with about 24 meters of window
line up generously about 13 meters. The 'loop' is kind of more like a
trapezoid but actually what is called a scalene.
"For my station I had very good propagation
conditions for the CQ 160m Phone contest. Heard ZF9, ZF2, PJ4 (2x), TO4,
C6, HQ9, OK7 and others I didn't write down. Didn't work any of them as
expected at 5 watts QRP phone.
"However, on February 24 at 0417 UTC I worked UA7K
with 5 watts on 1.838 LSB! At his twilight sunrise on the north-east
side of the Black Sea. Apparently one of those fabled 160m enhancements
at a station sunrise/sunset. Easy! Called once not expecting a thing.
A short pause on his end. I hear N8OQ. I give RR.
He gives me his CQ Zone 16. I report Victor Alpha Virginia. He gives
roger and in the log he goes. LOTW QSL received a few days later! WOW!
"The QSO was so easy I soon began to think I must have been hearing things, got the call sign wrong, something.
"I heard no big guns work him, but I heard at least
one other run-of-the-mill U.S. station work him for the few minutes I
paused to monitor him. When I checked again about 15 minutes later he
was gone but I then heard a Czech station and a Lithuanian but didn't
get them. Both also near their twilight sunrise line. My antenna and low
noise floor allow me to hear these stations that few if any others were
calling. The UA7K clearly also had a very low noise floor but is
apparently one of those super contest stations, Russian Contest Club. My
5 watts not enough to work any others of the good DX stuff--too bad! I
was tempted several times to turn on the amp but resisted! This is
currently my best of all time QSO.
"Was this QSO assisted by the auroral oval shifting away from the transatlantic path?"
I didn't have an answer for Jim but wanted to pass this on to readers.
Interesting article about solar activity from Canada's CBC:
https://www.cbc.ca/news/technology/solar-activity-1.5049337
Thanks, David Moore, for sending this link concerning massive solar storms:
https://www.sciencedaily.com/releases/2019/03/190311152744.htm
The latest video from Dr. Tamitha Skov, WX6SWW, can be found at, https://youtu.be/TSDfL9cwzEU .
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 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 March 7 through 13, 2019 were
14, 11, 11, 11, 11, 11, and 0, with a mean of 9.9. 10.7 cm flux was
70.9, 71.8, 70.7, 71.1, 70.4, 70.7, and 70.8, with a mean of 70.9.
Estimated planetary A indices were 8, 5, 5, 4, 3, 7, and 4, with a mean
of 5.1. Middle latitude A index was 5, 3, 4, 3, 3, 5, and 4, with a mean
of 3.9.
• All propagation reports can be found at:
http://www.southgatearc.org/propagation
