SB PROP @ ARL $ARLP039
ARLP039 Propagation de K7RA
ZCZC AP39
QST de W1AW
Propagation Forecast Bulletin 39 ARLP039
From Tad Cook, K7RA
Seattle, WA September 27, 2019
To all radio amateurs
SB PROP ARL ARLP039
ARLP039 Propagation de K7RA
Sorry, still no sunspots. Spaceweather.com reported on September 26
there were no sunspots for over 3 weeks, or 24 consecutive days.
Summer transitioned through the Autumnal Equinox last Monday,
September 23, and http://www.spaceweather.com noted that during the
northern Summer more than 89% of the days were spotless.
So far in 2019 the spotless days percentage is 72%, equal to what it
was in the last solar minimum in 2008 and 2009.
Passing the equinox is a good time for HF propagation, even with low
solar activity, and this is true whether you are now in Spring in
the Southern Hemisphere or Autumn in the Northern.
Over the past week (September 19-25) average daily solar flux
shifted marginally from 68.1 to 67.3, while average daily planetary
A index reflected quiet geomagnetic indices changing from 8.3 to 5.4
and mid-latitude indices went from 8 to 4.6.
Predicted solar flux is 67 on September 27 to October 4, and 68 on
October 5 through November 10.
Predicted planetary A index is 28, 45, and 20 on September 27-29, 12
on September 30 and October 1, 8 on October 2-3, 5 on October 4-5,
12 on October 6, 5 on October 7-9, then 8, 5, 8, 10, 8 and 8 on
October 10-15, then 5 on October 16-19, then 12 and 8 on October
20-21, 5 on October 22-24, then 25, 18, 10, 5 and 8 on October
25-29, then 5 on October 30 through November 1, 10 on November 2, 5
on November 3-5, then 8, 5, 8, 10 and 8 on November 6-10.
The planetary A index forecast of 28, 45 and 20 on September 27-29
is due to solar wind spewing from a large coronal hole. This is the
same hole that gave us the planetary A index of 38 and 45 on August
31 and September 1. Look for it again on October 25-26 after yet
another trip around the Sun.
Spaceweather.com reported in an email on September 26:
"GEOMAGNETIC STORM WARNING: A large hole in the Sun's atmosphere is
facing Earth and spewing a stream of solar wind in our direction.
NOAA forecasters say there is a chance of moderately-strong G2-class
geomagnetic storms when the gaseous material arrives on Sept. 28th.
The last such storm in early September produced auroras visible in
many northern-tier US states. Visit today's edition of
Spaceweather.com for more information and forecasts."
Geomagnetic activity forecast for the period September 27 until
October 22, 2019 from F.K. Janda, OK1HH.
"Geomagnetic field will be:
Quiet on: October 8, 16-17
Quiet to unsettled on: October 3-4, 7, 9, 20
Quiet to active on: October 1-2, 6, 10-11, 15, 18-19, 22
Unsettled to active on: September 30, October (5, 12-14,) 21
Active to disturbed: September 27-28, (29)
"Solar wind will intensify on: September 27-30, October 1 (-4, 7-9,)
11 (-14,) 21-23
"- Parenthesis means lower probability of activity enhancement.
- The predictability of changes remains lower."
Thanks to this week's ARRL Letter for these two references to a 1921
disturbance I had never heard of, rivaling the infamous Carrington
Event of 1859:
https://bit.ly/2lyoDZB
https://bit.ly/2lvwpDo
Bil Paul, KD6JUI, who operates ham radio from a kayak (detailed in
November 2016 QST) reported on September 26:
"I was operating from a kayak today (Thursday) running 10 watts into
an end-fed half-wave wire vertical antenna alongside the boat in
Lake Solano near Winters, CA.
"Was surprised to contact two French CW stations on 20 meters around
noon Pacific Time (1900 UTC). They gave me signal reports of 5/3 and
5/5. I gave them S6 and S7 reports. There was a little QSB.
"I did hear one station on 17 meters (CW) but no luck there. No luck either
on 30 meters. Good fishing!"
N4SO in Alabama reports FT8 contacts on 40 and 17 meters on
September 22-24:
"7.074 MHZ FT8 mode,
"Conditions are favorable on 40 meters, FT8 mode for Australia and
New Zealand every night after mid night. Here are examples on
September 24, (local times 1 AM, 2 AM, 3 AM, and 4 AM)
"065715 -13 0.2 1281 - CQ ZL4DC RE54 New Zealand
071915 -14 0.5 1692 - CQ VK2FAD QF56 Australia
080800 -19 0.4 860 - CQ VK7NET QE38 Australia
094830 -17 0.4 599 - CQ SA VK6IR OF77 Australia
"On 18.100 MHZ, FT8 mode, it was earlier noted that Australia is
possible on some days in the early evening hours before sunset. This
one is even earlier than before.
"2140 UTC or 4:40 PM Central time, September 22, calling CQ from
VK2DX with an immediate response.
"214245 -12 -0.1 1776 - N4SO VK2DX 73
(Australia)"
The latest from Dr. Tamitha Skov, WX6SWW:
https://youtu.be/rScJxk44OZE
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 web page 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 September 19 through 25, 2019 were 0, 0, 0, 0,
0, 0, and 0, with a mean of 0. 10.7 cm flux was 67.1, 67.2, 67.7,
68.3, 66.1, 67.1, and 67.5, with a mean of 67.3. Estimated planetary
A indices were 4, 3, 7, 4, 3, 13, and 4, with a mean of 5.4. Middle
latitude A index was 4, 3, 7, 2, 2, 11, and 3, with a mean of 4.6.
NNNN
/EX
