= NOW 18 WPM transition file follows =

With the big increase in sunspot numbers and solar flux reported in
last weeks Propagation Forecast Bulletin ARLP013, I hoped the trend
would continue, but numbers this week were lower.  Five new sunspot
groups emerged, one each day from March 30 through April 3.  Average
daily sunspot numbers went from 147 to 60, and average daily solar
flux declined from 191.9 to 136.9.  Geomagnetic numbers were much
quieter. Average daily planetary A index softened to 7.6 from 25.4.
Predicted solar flux is 115 on April 5 to 8, 120 on April 9 and 10,
125 on April 11, 140 on April 12 and 13, 150 on April 14 to 16, 160
on April 17 and 18, 170 on April 19 to 24, then 160, 150 and 140 on
April 25 to 27, then 130 on April 28 through May 4 then 160, 150,
and 140 on May 5 to 10, then 150 on May 11 to 13.  The predicted
flux values this week are much lower than in last weeks forecast for
the same period.  Predicted planetary A index is 16 and 10 on April
5 and 6, 5 on April 7 and 8, 8 on April 9 and 10, 5 on April 11 to
18, 8 and 10 on April 19 and 20, 8 on April 21 to 23, 5 on April 24
to 26, 10 on April 27 and 28, 8 on April 29, and 12 on April 30
through May 2, then 8, 5 and 5 on May 3 to 5, 8 on May 6 to 8, and 5
on May 9 to 15.  The Weekly Commentary on the Sun, the
Magnetosphere, and the Earths Ionosphere, April 4, 2024 from OK1HH.
The two large and very active sunspot groups, AR3614 and AR3615,
bade us farewell last week by going beyond the western limb of the
solar disk. AR3615 still unleashed two powerful M class flares and
an X1 flare that ionized the upper part of the Earths atmosphere and
caused the Dellinger effect, or shortwave fade, over the Pacific
Ocean on March 28, with a maximum at 2053 UTC.  AR3615 still managed
to produce an M9.4 class solar flare on March 30, which was only one
percent weaker than an X class flare. After that, we expected
particles originating from solar radiation to arrive in the vicinity
of Earth, but this did not happen. The development in the following
days was therefore relatively quiet.  Due to the calming of the
geomagnetic field, we expected an improvement in shortwave
propagation. This occurred from 2 April onwards but was only very
slight due to the rapid decrease in solar activity. After the return
of active regions to the solar disk, we expect an improvement in
propagation, especially in the third decade of April.  I think he
refers to a decade as a ten day period, so this would be the last
ten days of April.  Angel Santana, WP3GW, sent an email about last
weeks contest, WPX for me was pretty good even though I did not
reach my goal.  There were openings toward Europe during Saturday
midnight on 20 meters.  Now on Sunday at midday, I noticed a
reduction of stations on 10 meters, just like 2 weeks ago, but there
were many strong stations from South America and an hour later back
to normal. My friend Jose, KP4JRS, who operated as NP3YL, noticed
this over the two days on 10 meters.  Also noticed when a big
contest is on the air, the bands tend to be almost noiseless.  Not
sure if because the SFI has gone down but today Thursday at 1500 UTC
there is much noise on the bands. Hope the weekend fares better.
WX2R reminds us that coming up on Monday, April 8 is the HamSCI
Solar Eclipse QSO Party, Join with thousands of your fellow amateurs
as part of the largest crowd sourced event for ham radio scientific
exploration ever.  The SEQP is part of The Festivals of Eclipse
Ionospheric Science and is for learning more about how the
ionosphere works. Use any mode, any band for all or part of the day.
Participation can be from everywhere, you need not be near the path
of the eclipse to contribute valuable data by participating.  Or
just get on the air and help provide the data to better understand
the ionosphere.  Monday, 8 April 2024. Get on the air.  1400 to 2400
UTC.  Do it for science. Any band/any mode except 60, 30, 17, and 12
meters.  The links to articles on the Solar Eclipse QSO Party,
spaceweather, YO DX Cluster, flares, ARRL informational pages, solar
indices, and the recent video from Dr. Tamitha Skov, WX6SWW can be
found in teleprinter, packet, and Internet versions of Propagation
Forecast Bulletin ARLP014.  Sunspot numbers were 101, 79, 60, 50,
50, 35, and 45, with a mean of 60. 10.7 cm flux was 172.7, 167.3,
139.6, 133.6, 120.4, 112.8, and 111.7, with a mean of 136.9.
Estimated planetary A indices were 7, 6, 5, 9, 11, 8, and 7, with a
mean of 7.6. Middle latitude A index was 6, 4, 4, 8, 9, 7, and 10,
with a mean of 6.9.
= END OF 18 WPM transition file <