SB PROP @ ARL $ARLP005
ARLP005 Propagation de K7RAZCZC AP05
QST de W1AW
Propagation Forecast Bulletin 5 ARLP005
From Tad Cook, K7RA
Seattle, WA February 1, 2019
To all radio amateurs
SB PROP ARL ARLP005
ARLP005 Propagation de K7RA
The past week saw increased solar activity, with average daily
sunspot numbers rising from 5.3 to 19.6 and average daily solar flux
from 69.8 to 74.5. We haven’t seen such strong activity since the
beginning of last Summer, when Propagation Forecast Bulletin ARLP016
in 2018 reported average daily sunspot number at 22.6 and average
daily solar flux at 75.3.
But sunspots only persisted from January 22 through January 30, and
on January 31 they were gone.
Predicted solar flux is 72 on February 1-8, 69 on February 9-12, 72
on February 13-27, 70 on February 28 through March 3, 69 on March
4-11, and 72 on March 12-17.
Predicted planetary A index is 18, 12, 10, 8, 12 and 8 on February
1-6, 5 on February 7-18, then 12, 20, 12 and 8 on February 19-22, 5
on February 23-26, then 8, 18, 10 and 8 on February 27 through March
2, and 5 on March 3-17.
At 2314 UTC on February 31 the Australian Space Forecast Centre
issued a geomagnetic disturbance warning for the following day due
to a high speed solar wind stream from a recurrent coronal hole.
There is a chance of minor storm on Friday.
Geomagnetic activity forecast for the period February 1-27, 2019
from F.K. Janda, OK1HH.
“Geomagnetic field will be:
“Quiet on February 4-6, 8-9, 14, 24-26
Quiet to unsettled on February 7, 10, 17, 23, 27
Quiet to active on February 2-3, 13, 16, 18, 21-22
Unsettled to active on February 1, 11-12, 15, 20
Active to disturbed on February 19
“Solar wind will intensify on February (1,) 2-3, (4, 7, 19,) 20-21,
(22).
“Parenthesis means lower probability of activity enhancement.”
Report received from N0JK regarding FT8 activity on January 27:
“6 meter sporadic-E continued through the last week of January. Most
of the paths favored the Gulf Coast states and Mexico. Winter
sporadic-E tends to occur more frequently in these parts of North
America.
“I received a -21 report (21 dB below noise) from W4TAA EL87 at
0035z.
“I copied many decodes from XE2JS operating portable in rare grid
DL78, but no luck getting a reply. I copied XE2JS working N8JX and
KF8MY.”
The latest from Dr. Skov can be found at:
https://www.youtube.com/watch?v=bDPdyxfNWdA
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 January 24 through 30, 2019 were 19, 27, 26, 22,
16, 15, and 12, with a mean of 19.6. 10.7 cm flux was 73.5, 73.1,
75.8, 75.1, 76.6, 75, and 72.4, with a mean of 74.5. Estimated
planetary A indices were 19, 13, 7, 5, 1, 2, and 2, with a mean of
7. Estimated mid-latitude A indices were 13, 10, 5, 3, 0, 0, and 0,
with a mean of 4.4.
NNNN
/EX
