QST de W1AW  
Propagation Forecast Bulletin 18  ARLP018
>From Tad Cook, K7RA
Seattle, WA  May 3, 2019
To all radio amateurs 

SB PROP ARL ARLP018
ARLP018 Propagation de K7RA

No sunspots were visible over the recent reporting week (April 25
through May 1), and so the average daily sunspot number dropped to 0
after 8.1 during the previous seven days. Average daily solar flux
declined from 70.6 to 67.5. Geomagnetic indicators were quiet, with
average planetary A index at 5.9, up from 4.7 in the previous week.

The predicted solar flux is 72 on May 3-5, 75 on May 6-9, 78 on May
10-16, then 76, 72 and 70 on May 17-19, 69 on May 20-21, 68 on May
22, 67 on May 23 through June 2, 70 and 75 on June 3-4, 78 on June
5-12, then 76, 72, 70 and 69 on June 13-16.

The predicted planetary A index is 5 on May 4-9, 8 on May 10, 5 on
May 11-19, 8 on May 20, 5 on May 21-26, then 10, 14, 12, 8 and 5 on
May 27-31, then 10, 12 and 14 on June 1-3, 8 on June 4-6, and 5 on
June 7-15, then 8 on June 16.

Interesting article in the New Yorker about Aurora Borealis tourism:

https://bit.ly/2UvvVbN

A video posted last week from Dr. Tamitha Skov, WX6SWW:

https://youtu.be/W9Fp-O3Ddlo

Geomagnetic activity forecast for the period May 3-30, 2019 from
F.K. Janda, OK1HH.

'Geomagnetic field will be:
quiet on May 15, 19, 22-23
quiet to unsettled on May 6, 8-16, 18, 24-27
quiet to active on May 3-5, 17, 21, 28
unsettled to active on May 7, 20, 29-30

'No Active to Disturbed conditions are forecast.

'Solar wind will intensify on May 3-4, 9-13, 15, (20,) 22-23, 30

'Parenthesis means lower probability of activity enhancement.'

Thanks to M0VNG and others for the tip to this article on moving
geomagnetism:

https://bit.ly/2IWoqJA

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 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/.

Monthly propagation charts between four USA regions and twelve
overseas locations are at arrl.org/propagation.

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

Sunspot numbers for April 25 through May 1, 2019 were 0, 0, 0, 0, 0,
0, and 0, with a mean of 0. 10.7 cm flux was 67.5, 67.2, 66.9, 67.9,
66.9, 68.5, and 67.6, with a mean of 67.5. Estimated planetary A
indices were 5, 4, 6, 5, 5, 5, and 11, with a mean of 5.9. Middle
latitude A index was 4, 2, 5, 4, 6, 4, and 8, with a mean of 4.7.