QST de W1AW  
Propagation Forecast Bulletin 27  ARLP027
>From Tad Cook, K7RA
Seattle, WA  July 6, 2018
To all radio amateurs 

SB PROP ARL ARLP027
ARLP027 Propagation de K7RA

No sunspots have appeared since June 26. If we use predicted solar
flux as a proxy, flux is expected to be less than 70 until July 8,
this Sunday, so I would not expect sunspot activity to resume
perhaps until July 13 to 23 when solar flux is expected to rise
above 70.

Predicted solar flux is 68 on July 6 and 7, 70 on July 8 to 12, 72
on July 13, 75 on July 14 and 15, 77 on July 16, 80 on July 17 to
19, 77 on July 20 and 21, 73 and 71 on July 22 and 23, 70 on July 24
and 25, 69 on July 26 and 27, 68 on July 28 to August 5, 69 on
August 6, 72 on August 7 to 9, 75 on August 10 and 11, 77 on August
12, 80 on August 13 to 15, 77 on August 16 and 17, then 73 and 71 on
August 18 and 19.

Predicted planetary A index is 10 on July 6, 5 on July 7 to 14, then
15 on July 15, 5 on July 16 to 19, then 15, 8, 10, 18 and 7 on July
20 to 24, 5 on July 25 to 28, 8 on July 29, 5 on July 30 through
August 10, 15 on August 11, 5 on August 12 to 15, then 15, 8, 10 and
18 on August 16 to 19.

Chip Margelli, K7JA had a comment on the coverage of Field Day
conditions last week:

'Hi Tad.

Saw your propagation report re Field Day. Still trying to figure out
which planet that represented.

Conditions on FD were generally awful. The K index rising to 4
Saturday morning really tore up the bands, and blew out the E layer
out west. Neither six nor 10 opened up at all on Saturday, and there
were only a few pop-up paths that emerged on Sunday on ten. On six,
while much of the eastern part of the country had a big band, in
southern California we worked five whole stations in South Dakota.
That was it.

Twenty was 'fair,' but it closed early Saturday night. Fifteen was a
huge bust, and 40 was very disturbed, with heavy QSB and east coast
signals generally huddling right at the edge of being audible.
Forty never really took off to the east, causing us to be at least
30% off of our anticipated numbers.

Not a good weekend for prop at all. And very disappointing, because
six had been wide open all week before FD, and here a week after FD
it is again open across the country. Just not the Saturday and
Sunday of FD.

Sigh.

73 de Chip K7JA'

For more information concerning radio propagation, see the ARRL
Technical Information Service 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 June 28 to July 4, 2018 were 0, 0, 0, 0, 0, 0,
and 0, with a mean of 0. 10.7 cm flux was 69.5, 68.6, 68.8, 68.1,
66.6, 68.2, and 67.9, with a mean of 68.2. Estimated planetary A
indices were 5, 4, 4, 3, 3, 4, and 5, with a mean of 4. Estimated
mid-latitude A indices were 5, 3, 3, 4, 4, 5, and 4, with a mean of
4.