[RSM] W3LPL prop forecast for Friday/12

[Art Boyars]

W3LPL says it's OK to forward these to RSM Reflector.  There is some delay
between when Frank sends and when I receive (think of e-mail as a sort of
SDR).  Thus, the reports might not be timely.  Also, some days I will not
send at all.

After we do this for a week or so I'll want to know if anybody on the RSM
Reflector finds it useful.  If not, we'll QRT.

73, Art K3KU/VE4VTR


From: donovanf at erols.com
To: pvrc reflector <pvrc at mailman.qth.net>
Cc:
Bcc:
Date: Fri, 12 Mar 2021 01:34:58 -0500 (EST)
Subject: [PVRC] Mostly below normal propagation is likely Saturday

Long distance propagation forecast for Friday through Sunday, March 12-14

My propagation forecast derived from today's NOAA/SWPC web

pages is published five days a week (M-F) in the Daily DX.



Low latitude propagation is likely to be normal through at least

Sunday. Mid-latitude, auroral zone and polar propagation is likely

to be normal until late Friday, then mostly below normal during

Saturday and returning to mostly normal early on Sunday.



Click *here* <https://services.swpc.noaa.gov/images/planetary-k-index.gif>
for today’s
latest planetary Kp Index, updated every three hours.

Click *here* <http://www.hamqsl.com/solar.html> for N0NBH’s current HF Band
Conditions, updated regularly.



The solar flux index (SFI) is likely to remain at about 78 though

at least Sunday. There are two tiny solar regions on the visible disk,

one is growing and may increase the SFI and affect HF propagation

on Sunday if it continues to grow.



We are in the March-April geomagnetic storm season when the earth

passes through the part of the interplanetary magnetic field (IMF)

with more frequent, longer duration southward oriented magnetic

field. Approximately twice as many brief minor and moderate

geomagnetic storms occur during March and April compared to the

quieter IMF during June and July. Brief minor to moderate

geomagnetic storms may be triggered with little warning when the

IMF rotates to a southward orientation and persists for several hours

*coincident with* the effects of earth directed coronal hole high speed

stream enhancements in the solar wind.



160 through 17 meter low latitude propagation is likely to be normal

through at least Sunday.



160 and 80 meter mid-latitude propagation is likely to be normal

until late Friday, then mostly below normal during Saturday and

returning to mostly normal early on Sunday. 160 and 80 meter

short path propagation to south Asia is likely to be mostly below

normal at 0200Z through Sunday. 80 meter short path propagation

from North America to east Asia is likely to be mostly below normal

through early Sunday. 80 meter long path propagation from North

America to southeast Asia at about 2330Z is likely to be mostly

below normal on Friday and Saturday and normal on Sunday.



40 meter mid-latitude propagation is likely to be normal until late

Friday, then mostly below normal during Saturday and returning to

mostly normal early on Sunday. 40 and 30 meter long path

propagation from North America to southeast Asia at about 2330Z

is likely to be mostly below normal on Friday and Saturday and

normal on Sunday.



30 meter mid-latitude, auroral zone and polar propagation is likely

to be normal until late Friday, then mostly below normal during

Saturday and returning to mostly normal early on Sunday. 30 meter

propagation is always significantly degraded within a few hours of

local noon because of E-region blanketing of long distance F2

propagation. 30 meter propagation is unreliable during most of the

night in the northern hemisphere because of insufficient residual

night time F region electron density due to tiny sunspots on the earth

facing solar disk.



20 meter daytime mid-latitude, auroral zone and polar propagation

is likely to be normal until late Friday, then mostly below normal

during Saturday and returning to mostly normal early on Sunday.

Night time 20 meter propagation in the northern hemisphere

continues to be very unreliable because of insufficient residual

F region electron density due to tiny sunspots on the earth facing

solar disk.



17 and 15 meter daytime mid-latitude propagation in the northern

hemisphere continues to be shorter in duration because of

insufficient F2 region electron density due to tiny sunspots on the

visible solar disk. 12 and 10 meter daytime propagation is likely to

be unreliable and mostly limited to propagation from North America

to Southern Africa, South Atlantic, South America and South Pacific regions.



Geomagnetic storms and active geomagnetic conditions *caused by*

*coronal hole high speed streams* are likely to remain mostly brief,

minor and relatively infrequent through at least late 2021. Brief minor

to moderate geomagnetic storms may be triggered when the IMF persists

in a southward orientation (-Bz) with enhanced field strength for several

hours *coincident with* the effects of earth directed coronal hole high
speed

stream enhancements in the solar wind.



IMF field strength, solar wind speed near earth and geomagnetic activity

are likely to be at background levels on Friday. Starting late Friday IMF

field strength, solar wind speed near earth and geomagnetic activity are

likely to be enhanced by coronal hole high speed stream interactions with

the solar wind then gradually diminishing to near nominal levels early

Sunday as the effects of a coronal hole high speed stream gradually wane.

There is a risk of a brief minor geomagnetic storm early Saturday if the

IMF persists in a southward orientation (-Bz) with enhanced field strength

for several hours.



Earth directed CMEs or solar flares strong enough to affect HF

propagation are not likely through at least Sunday.



Northern hemisphere daylength is 143 minutes longer than it was on

December 21st. Sunset is now 87 minutes later than it was on

December 9th. Daylength is increasing by two minutes per day which

is steadily reducing the duration of common darkness between distant

locations in the northern hemisphere.



Click *here* <https://www.spaceweather.gc.ca/solarflux/sx-4-en.php> for today’s
Penticton 10.7 cm solar flux index updated at 1800Z, 2000Z and 2200Z daily.

Click *here*
<https://spaceweather.gfz-potsdam.de/fileadmin/ruggero/Kp_forecast/forecast_figures/KP_FORECAST_CURRENT.png>
for today’s
three-day GFZ Planetary K Index forecast updated every three hours.

Click *here* <http://sidc.oma.be/products/meu/> for today's SIDC Daily
Bulletin on Solar and Geomagnetic Activity updated at 1230Z daily.

Click *here* <https://www.swpc.noaa.gov/products/forecast-discussion>
for today's
SWPC Solar Activity Forecast Discussion updated at 0030Z and 1230Z daily.

Click *here* <https://www.sws.bom.gov.au/Space_Weather/1/1> for today's
Australian Space Forecast Centre Summary and Forecast updated at 2330Z
daily.



Perhaps the most useful HF propagation pages for DXers can be found at:

dx.qsl.net/propagation and www.solarham.net and hamqsl.com/solar.html
<http://www.hamqsl.com/solar.html>