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 25, 2017
To all radio amateurs

SB PROP ARL ARLP034
ARLP034 Propagation de K7RA

All solar indicators rose over the past week (August 17 to 23), with average
daily sunspot number increasing from 15.3 to 39.9, and average daily solar flux
 from 72 to 84.6, compared to the previous seven days.

Predicted solar flux is 79 on August 25, 80 on August 26, 78 on August 27 to
30, 75 on August 31, 78 on September 1 and 2, 75 on September 3 to 7, 80 on
September 8, 85 on September 9 to 14, 88 on
September 15 and 16, 90 on September 17 to 22, 85 and 80 on September 23 and
24, 78 on September 25 to 29, 75 on September 30 through October 4, 80 on
October 5, and 85 on October 6 to 8.

Predicted planetary A index is 8 on August 25, 5 on August 26 and 27, 8 on
August 28 and 29, 10 on August 30, 18 on August 31 to September 1, 14 on
September 2, 5 on September 3 to 7, then 10 and 8 on September 8 and 9, then 5
on September 10 to 12, 25 on September 13, 30 on September 14 and 15, then 25,
8, 10 and 6 on September 16 to 19, 5 on September 20 to 25, then 12, 24, 18 and
 14 on September 26 to 29, 5 on September 30 through October 4, and 10 and 8 on
 October 5 and 6 and 5 October 7 and 8.


And now from our correspondents in Eastern Europe:

"Solar activity forecast for the period August 25 to August 31, 2017

Activity level: mostly low
X-ray background flux (1.0 to 8.0 A): in the range A8.0 to B4.5
Radio flux (10.7 cm): a fluctuation in the range 75 to 95 f.u.
Events: class C (0 to 5/day), class M (0 to 4/period), class X (0/period),
proton (0/period)
Relative sunspot number (Ri): in the range 11 to 80

Martina Exnerova
RWC Prague, Astronomical Institute, Solar Dept., Ondrejov, Czech Republic


Geomagnetic activity forecast for the period August 24 to August 31, 2017

Quiet: Aug 26 to 29
Unsettled: Aug 24 and 25, 30 and 31
Active:    Aug possible Aug 31
Minor storm: 0
Major storm: 0
Severe storm: 0

Geomagnetic activity summary:
Currently, an active episode has been recorded.  At the Budkov observatory, the
 local K-index did not exceed level 4.

Thursday, August 24, we expect at most unsettled conditions.  Next day, Friday,
 August 25, we expect geomagnetic activity decrease to quiet to unsettled
level.

Quiet to unsettled conditions are predicted for the rest of forecast period. 
At the end of August, active episode is possible about August 31.

Tomas Bayer
RWC Prague
Institute of Geophysics of the ASCR, Prague
Department of Geomagnetism
Budkov observatory (BDV)"


Did you witness the eclipse on Monday?  I found a group of my neighbors
gathered on the street corner after 1700 UTC, and they had one of those
taped-together box arrangements for projecting the image.  We were in Seattle,
north of the band of darkness that spread over northern Oregon.  Someone drove
by with a box of those special safe eclipse glasses, and they worked very well.

Reports from friends who travelled to Madras, in Eastern Oregon's Jefferson
County reported that in the middle of the totality band they saw the sky go
totally dark, and stars illuminated the sky.


Scott Craig, WA4TTK of Nashville, Tennessee sent this, along with a link to
eclipse photos he took:

"Thought you might like these.  They are photos of Monday's eclipse taken here
in Nashville.  I took them and keep looking at them because I find them
fascinating."

http://sc-photo-tn.com/?page_id=2389



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-ionosph...

An archive of past propagation bulletins is at
http://arrl.org/w1aw-bulletins-archive-propag...  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 17 to 23, 2017 were 30, 41, 33, 44, 43, 48, and 40,
with a mean of 39.9. 10.7 cm flux was 76.7, 80, 86.8, 86, 87.1, 90.2, and 85.1,
 with a mean of 84.6.  Estimated planetary A indices were 29, 21, 31, 22, 11,
23, and 25, with a mean of 23.1. Estimated mid-latitude A indices were 20, 20,
23, 21, 13, 16, and 17, with a mean of 18.6.

NNNN
/EX

)\/(ark

Always Mount a Scratch Monkey
Do you manage your own servers? If you are not running an IDS/IPS yer doin' it
wrong...
... "Vesele Vianoce. A stastlivy Novy Rok." - Slavak Christmas
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