[RSM] W3LPL: Normal Tue, then down at mid-to-hi-latitudes after early Wed

Art Boyars artboyars at gmail.com
Tue Jan 3 02:06:44 EST 2023


From: Frank Donovan <donovanf at starpower.net>
To: PVRC <pvrc at mailman.qth.net>
Cc:
Bcc:
Date: Tue, 3 Jan 2023 02:00:39 -0500 (EST)
Subject: [PVRC] Propagation is likely to be mostly normal on Tuesday then
degrading at mid to high latitudes after early Wednesday

My propagation forecast derived from today's NOAA/SWPC web pages
is published five days a week (M-F) in the Daily DX. All days and times in
this forecast are in UTC (Zulu) time.

Propagation crossing low latitudes is likely to be normal through Wednesday.

Propagation crossing mid-latitudes is likely to be normal on Tuesday
degrading to mostly normal after early Wednesday.

Propagation crossing the auroral ovals and polar regions is likely to be
mostly normal on Tuesday degrading to mostly below normal during local
night time hours after early Wednesday.

Click https://services.swpc.noaa.gov/images/station-k-index.png for today's
latest estimated planetary Kp Index, updated every three hours.

Click http://www.hamqsl.com/solar.html for N0NBH's current HF
Band Conditions, updated regularly.

Today's solar flux index (SFI) is 146 and is likely to remain about the
same through Wednesday. The sun’s visible disk has one large, three medium
and two tiny active regions containing 34 sunspots with a total sunspot
area of 1100 micro-hemispheres (about six times the surface area of the
Earth).
https://www.sidc.be/spaceweatherservices/applications/solarmap

160 and 80 meter propagation from North America to VK/ZL and
the south Pacific is likely to be normal through Wednesday.

40 meter short path propagation from North America to south Asia at about
0000Z is likely to be mostly normal early Wednesday. Short path propagation
from North America to east Asia after about 0800Z is likely to be mostly
normal on Tuesday and mostly below normal on Wednesday. 40 meter long path
propagation from North America to east Asia after about 2130Z is likely to
be normal on Tuesday and mostly normal on Wednesday.

30 meter propagation through the auroral ovals and polar regions is likely
to be mostly normal on Tuesday degrading to mostly below normal during
local night time hours after early Wednesday. 30 meter long path
propagation from North America to east Asia after about 2130Z likely to be
normal on Tuesday and mostly normal on Wednesday. 30 meter propagation is
always significantly degraded within a few hours of local noon by E-region
blanketing of long distance F2 propagation.

20 meter daytime and evening propagation through the auroral ovals
and polar regions is likely to be mostly normal on Tuesday degrading to
mostly below normal during local night time hours after early Wednesday. 20
meter transpolar propagation within a few hours of sunrise and sunset is
likely to be mostly normal through mid-day Wednesday degrading to mostly
below normal during local night time hours after early Wednesday.

17 and 15 meter long distance propagation is likely to be mostly normal on
Tuesday degrading to mostly below normal during local night time hours
after mid-day Wednesday.

12 and 10 meter long distance propagation is likely to be mostly normal on
Tuesday degrading to mostly below normal during local night time hours
after early Wednesday. 12 and 10 meter long path propagation from North
America to east Asia from about 1200Z to 1400Z is likely to be mostly
normal on Tuesday degrading to mostly below normal on Wednesday. 12 and 10
meter F2 propagation crossing northern hemisphere mid-latitudes is likely
to be enhanced when the solar flux index is about 120 or higher and
geomagnetic activity is quiet to unsettled (K index of 3 or less).

Very long distance 6 meter oblique trans-equatorial propagation (TEP) from
North America mostly to CQ Zone 32 is likely to occur infrequently through
early January from the southern tier of U.S. states during mid-afternoon at
the path mid-point (evening hours in the eastern U.S.). More northerly U.S.
locations may infrequently couple into trans-pacific oblique TEP via
occasional sporadic-E paths to W5 and XE. See K6MIO’s excellent article
beginning on page 66 at:
https://k5tra.net/TechFiles/2014%20Central%20States%20whole%20book.pdf

Persistent southward orientation (-Bz) of the north-south component of the
interplanetary magnetic field (IMF) plays a crucial but unpredictable role
in triggering all geomagnetic storms. Brief minor to moderate
geomagnetic storms may be gradually triggered when the IMF persists in a
southward orientation (-Bz) with IMF field strength of about 5 nanoteslas
for several hours coincident with the effects of an Earth directed
coronal hole high speed stream. More frequent, longer duration, minor
to severe geomagnetic storms may be triggered suddenly and
unpredictably when the IMF persists in a southward orientation (-Bz) with
IMF field strength significantly stronger than 5 nanoteslas for several
hours or more coincident with the effects of an Earth directed fast CME
(faster than 1000 km per second). Real time geomagnetic data including Bz
orientation, IMF field strength, solar wind speed and short term K Index
forecast are available here:
www.swpc.noaa.gov/products/geospace-geomagnetic-activity-plot

There is a chance of minor to moderate daytime radio blackouts caused by
unpredictable sudden bursts of X-ray radiation from M-class solar flares
through Wednesday due to the large number of active regions on the visible
disk.

Solar wind speed is likely to decrease to near background levels through
early Wednesday due to waning coronal hole high speed stream effects.  Wind
speed is likely to become enhanced after early Wednesday due to coronal
hole high speed stream and possible weak CME effects.

Geomagnetic activity is likely to be mostly quiet through early Wednesday
due to waning coronal hole high speed stream effects. Active to minor storm
conditions are likely after early Wednesday due to coronal hole high speed
stream and possible weak CME effects. We are in the winter solstice season
when disturbed geomagnetic conditions occur about half as often as during
the spring and fall equinox seasons.

Mid-latitude northern hemisphere sunset is nine minutes later and day
length is five minutes longer than it was on December 21st.

Click
https://www.spaceweather.gc.ca/forecast-prevision/solar-solaire/solarflux/sx-5-flux-en.php
for the Penticton 10.7 cm solar flux index updated daily at 1800, 2000 and
2200Z .

Click
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
https://www.sidc.be/spaceweatherservices/data/ClassicalRWCproducts/meu
for today's SIDC Daily Bulletin on Solar and Geomagnetic Activity updated
at 1230Z daily.

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

Click 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:
http://dx.qsl.net/propagation and http://www.solarham.net


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