QST de W1AW  
Propagation Forecast Bulletin 40  ARLP040
>From Tad Cook, K7RA
Seattle, WA  October 2, 2020
To all radio amateurs 

SB PROP ARL ARLP040
ARLP040 Propagation de K7RA

Solar wind disturbed HF conditions this past week, September 24-30.

Average daily planetary A index rose from 5.1 to 22, while average
middle latitude A index went from 5 to 15.6. Average daily sunspot
number declined from 1.9 to 1.6; a weak sunspot only appeared on two
dates, September 23 and 25, with sunspot numbers of 13 and 11,
respectively.

Average daily solar flux was on the increase, edging up from 71.1 to
73.4.

Predicted solar flux for the next 45 days is 73 on October 2-4, 70
on October 5-18, 72 on October 19-31, 70 on November 1-14 and 72 on
November 15.

Predicted planetary A index is 12 and 8 on October 2-3, 5 on October
4-10, 10 on October 11, 5 on October 12-19, then 10, 18 and 20 on
October 20-22, then 24, 16, 38 and 38 on October 23-26, then 26, 15
and 10 on October 27-29, 5 on October 30 thru November 6, 10 on
November 7, and 5 on November 8-15.

Geomagnetic activity forecast for the period October 1-27, 2020 from
OK1HH.
 
'Geomagnetic field will be 
quiet on: October 6-7 
quiet to unsettled on: October 5, 13-16 
quiet to active on: October 1-2, (3-4, 8- 9, 12, 17,) 18-19 
unsettled to active: October 10-11, 20, 22, (24,) 27 
active to disturbed: October 21, 23, (25-26) 
 
'Solar wind will intensify on: October 1-3, 13-14, (15, 20-25,)
26-27.

'Parenthesis means lower probability of activity enhancement.'

Here is an article about the European Space Agency Solar Orbiter:

https://bit.ly/2GxUX8P

Southgate Amateur Radio has a 10 meter report:

https://bit.ly/34gkTOK

W6MVT in Southern California was pleasantly surprised after erecting
a new vertical. His first catch was E51JD from the South Cook
Islands on 28 September at 0022 UTC. This was his first SSB DX on 15
meters in many years, though the opening vanished as quickly as it
came.

Jeff, N8II reported last Saturday, September 26:

'Solar storm today, early about 1400-1500Z skip was shorter than
normal (NJ and NC on 40) and W9-land on 20 along with a few ME/NB
stations (Maine QSO Party this weekend), but after a good run of 5s,
6s, 7s, and 0s on 20 SSB this afternoon the condx are very poor as
of 2015Z. The storm is in full force.'

Ken, N4SO shared this from the Alabama Gulf Coast:

'A wealth of information is available from the following:

'www.reversebeacon.net/beacons/beacons_ncdxf.php

'Also, one more Beacon on 21.150 MHZ is heard to add to LU4AA, OA4B,
YV5B.

'W6WX is often heard at this location near 2300-0000 UTC. His
signals are strong enough to hear at 100 watts and 10 watts.'

If you would like to make a comment or have a tip for our readers,
email the author at, [email protected] .

For more information concerning radio propagation, see
www.arrl.org/propagation and the ARRL Technical Information
Service web page at, arrl.org/propagation-of-rf-signals. For an
explanation of numbers used in this bulletin, see
arrl.org/the-sun-the-earth-the-ionosphere.

An archive of past propagation bulletins is at
arrl.org/w1aw-bulletins-archive-propagation. More good
information and tutorials on propagation are at k9la.us/.

Instructions for starting or ending email distribution of ARRL
bulletins are at arrl.org/bulletins.

Sunspot numbers for September 24 through 30, 2020 were 0, 11, 0, 0,
0, 0, and 0, with a mean of 1.6. 10.7 cm flux was 73.6, 73.4, 72.6,
74.1, 73.9, 72.8, and 73.3, with a mean of 73.4. Estimated planetary
A indices were 19, 20, 27, 24, 33, 16, and 15, with a mean of 22.
Middle latitude A index was 11, 17, 18, 16, 21, 14, and 12, with a
mean of 15.6.