During our reporting week (March 21-27) solar activity increased while
geomagnetic indicators were lower, compared to the previous seven days. This is
a nice combination for the first week of spring.
Although sunspots and solar
flux decreased toward the end of the period, average daily sunspot numbers
doubled from 8 to 16, and average daily solar flux increased from 70.7 to
75.2.
Average daily planetary A index decreased from 8.1 to 3.7, and average
daily middle latitude A index decreased from 6.3 to 3.9.
These numbers are
all good, because higher sunspot numbers and solar flux suggest better
enhancement of the ionosphere while the lower geomagnetic numbers correspond to
generally lower absorption or disturbed conditions.
The planetary A index is
a composite from magnetometers around the globe, but the middle latitude A index
is from a single magnetometer in Virginia.
Predicted solar flux from the
March 28 forecast is 68 on March 29 through April 4, 70 on April 5-6, then 71
and 74 on April 7-8, 75 on April 9-18, then 74, 73, 73 and 71 on April 19-22, 70
on April 23 through May 3, 71 and 74 on May 4-5, and 75 on May
6-12.
Predicted planetary A index is 12 on March 29, 8 on March 30 through
April 2, 6 and 8 on April 3-4, 5 on April 5-11, then 15 and 10 on April 12-13, 5
on April 14-21, then 8, 12, 12, 8 and 8 on April 22-26, 5 on April 27-28, 8 on
April 29-30, 5 on May 1-8, then 12, 8, 5 and 5 on May 9-12.
The above
predictions for solar flux and A index are updated daily at
ftp://ftp.swpc.noaa.gov/pub/forecasts/45DF/ .
There have been no sunspots
on March 26-28. Here is an image of sunspot group AR2736 from March 23, a few
days before it disappeared: https://bit.ly/2utHqGj
From F.K. Janda,
OK1HH:
Geomagnetic activity forecast for the period March 29 until April 27,
2019
Geomagnetic field will be:
Quiet on March 31, April 11, 16, 18-21,
27
Quiet to unsettled on March April 1-4, 11-12, 22, 25-26
Quiet to active
on March 30, April 6-10, 15, 23-24
Unsettled to active on March 29, April 5,
13-14, 17
Solar wind will intensify on March 29 (- 30), April (2-6,) 12-13,
15-16. Parenthesis means lower probability of activity enhancement.
NN4X
sent this report: “On March 26 I tried 17 meters and worked into Australia and
New Zealand on a seemingly dead band. I worked E6 on 3/27 at 21:41Z. Additional
countries worked included Spain, France, St Helena, and Yugoslavia. I had to
leave after 5:00 PM local so was not able to look west for any late
afternoon/early evening openings, although I don't see anything posted to DX
Cluster.
“On March 28 I decided to call CQ into a ‘dead’ 12-meter band, and
soon saw PSKReporter.info showing I was heard in Spain. I continued calling and
soon made contacts with Spain, Brazil, Puerto Rico, and Argentina. I was also
heard in France.
“Once again, it pays to make some noise; you never know
who's listening, or where."
The CQ World Wide WPX SSB Contest is this
weekend. See https://www.cqwpx.com/
The latest from Dr. Tamitha Skov,
WX6SWW: “What happened nationwide this past week [the media hyping of a ‘solar
storm’] was a tragedy-- it did not need to happen. It's always personally
painful to me when some members of the media jump on these storms and hype them
beyond recognition. Seduced by the allure of aurora views and a world of
science-fiction adventure, people from all over then embark on a solar storm
crusade. They pack their bags, and their cars, and head hundreds of miles
towards the poles singing victory songs with stars in their eyes. Their trip
begins with enthusiasm, awe, and wonder, but it ends tragically. It leaves many
feeling confused and left out in the dark and cold (literally) as they look
skyward for an aurora show that never comes.
“Events like these are stark
reminders of why it’s so critical we continue to push forward to create a field
of Space Weather broadcasting. When the media runs amok, omitting critical
aspects of Space Weather that make forecasting so difficult and aurora so
elusive, it traps everyone in its web. You, me, and especially the uninitiated.
But there is a bright spark I am beginning to see. Far more than ever before, I
saw this community push back on the hype. What is more-- I watched as
journalists and meteorologists alike, learned from us. As in the picture above,
I saw proof we are winning the battle. We are slowly pushing back against the
media veil that continues to keep Space Weather shrouded in mystery. I know a
huge part of our success is due to you, and I am eternally grateful.
“As for
this week's forecast, our Sun calms down a bit as rogue region 2736 rotates to
the Sun's backside. We won't see it again for another two weeks. This means
emergency, shortwave, and amateur radio propagation tanks again on Earth's day
side, even as GPS reception improves. We also get another chance for a solar
storm from a small pocket of fast wind that is already brightening the aurora
again. So at least that is good news for aurora hopefuls, who missed out on the
show this past week. Too bad no media are reporting on the aurora viewing
chances now. They're better than during the peak of the hype. So much for a
fizzle and a frenzy.”
See Dr. Skov’s latest video here:
https://youtu.be/I4TiyYm1u4s
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 21 through 27, 2019 were
49, 27, 22, 14, 0, 0, and 0, with a mean of 16. 10.7 cm flux was 80.1, 82.4,
79.4, 75.4, 71.2, 69, and 68.9, with a mean of 75.2. Estimated planetary A
indices were 2, 1, 1, 3, 5, 6, and 8, with a mean of 3.7. Middle latitude A
index was 2, 2, 2, 3, 5, 5, and 8, with a mean of 3.9
