SB PROP @ ARL $ARLP034
ARLP034 Propagation de K7RA
ZCZC AP34
QST de
W1AW
Propagation Forecast Bulletin 34 ARLP034
From Tad Cook,
K7RA
Seattle, WA August 23, 2019
To all radio amateurs
SB PROP
ARL ARLP034
ARLP034 Propagation de K7RA
Spotless days continue this
week, with consecutive days without
sunspots now at 16 days, according to
spaceweather.com as of August
22.
Average daily solar flux for all
practical purposes was unchanged,
from 67.4 last week to 67.5 this week.
Average daily planetary A
index went slightly lower from 6.3 to
4.4.
Predicted solar flux looks the same as it has been for months
now,
at 67 on August 23 to September 11, 68 on September 12 to 21 and
67
again on September 22 through October 6.
The forecast for
planetary A index stands at 5 on August 23 to 25,
then 12, 12 and 8 on August
26 to 28, 5 on August 29 to 31, then
with a recurring coronal hole, 38 and 14
on September 1 and 2, 5 on
September 3 to 5, 8 on September 6 and 7, then 5
on September 8 to
15, 7 on September 16 and 17, 6 on September 18, 5 on
September 19
to 21, 8 on September 22 to 24, 5 on September 25 to 27, then
with
the return of that coronal hole 38 and 14 on September 28 and 29,
5
on September 30 through October 2, 8 on October 3 and 4 and 5 on
October
5 and 6.
Geomagnetic activity forecast for the period August 23 to
September
18, 2019 from F. K. Janda, OK1HH who has issued weekly
forecasts
since January, 1978.
"Geomagnetic field will
be:
Quiet on: September 4 and 5, 9 to 15
Quiet to unsettled on:
August 29 to 31, September 3, 6 to 8
Quiet to active on: August (23 to 25,)
September 16 to 18
Unsettled to active on: August (26 to 28), September 2
Active to disturbed: September 1
Solar wind will intensify on:
August 27 to 29, (30 and 31,)
September 1 and 2, (4 to 7)
Parenthesis
means lower probability of activity enhancement."
There was an error in
last week's bulletin, in which we
misidentified a call sign from Reunion
Island when it was really St.
Pierre et Miquelon. Because of the proximity
to Nova Scotia, I
always thought it part of Canada, but it is really a
French
possession.
Ken, N4SO reports working XP3A (Greenland) with
FT8 on 18.1 MHz, a
new one for him.
Interesting course from WX6SWW
about indices:
https://www.youtube.com/watch?v=zVgZQqUYemc
And
her latest forecast:
https://youtu.be/GlpdWxXUnAk
Curious
about spotless days?
http://www.sidc.be/silso/spotless
Note
that 1954 had more spotless days than last year, and it was
just prior to the
biggest solar cycle (cycle 19) in recorded
history.
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 August 15 through 21, 2019 were 0, 0, 0, 0, 0,
0, and 0, with a
mean of 0. 10.7 cm flux was 67.6, 67.5, 68, 67.5,
67.7, 67.3, and 66.8, with
a mean of 67.5. Estimated planetary A
indices were 4, 5, 4, 6, 4, 4, and 4,
with a mean of 4.4. Middle
latitude A index was 4, 6, 6, 7, 4, 7, and 5,
with a mean of 5.6.
NNNN
/EX
