[RSM] W3LPL: Tue, Wed mostly normal; maybe some down

[Art Boyars]

From: Frank W3LPL <donovanf at starpower.net>
To: PVRC <pvrc at mailman.qth.net>
Cc:
Bcc:
Date: Tue, 24 Jan 2023 01:30:47 -0500 (EST)
Subject: [PVRC] Propagation is likely to be mostly normal through Wednesday
but with possible mildly depressed conditions on mid and high latitude
paths from late Tuesday through 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 through Wednesday
but with a chance of mildly depressed conditions from late Tuesday through
early Wednesday.

Propagation crossing the auroral ovals and polar regions is likely to be
mostly normal through Wednesday but with possible moderately depressed
conditions from late Tuesday through early Wednesday.

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. . Today's solar flux index (SFI) is 189 and
is likely to remain about the same through at least Wednesday. The sun’s
visible disk has one very large, four medium and four tiny active
regions containing 54 sunspots with a total sunspot area of 1240
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 through Wednesday with possible
moderately depressed conditions from late Tuesday through early Wednesday.
Short path propagation from North America to east Asia after about 0800Z is
likely to be mostly normal through Wednesday. 40 meter long path
propagation from North America to east and southeast Asia after about 2145Z
is likely to be mostly normal with possible moderate degradation on Tuesday
improving to mostly normal on Wednesday.

30 meter propagation through the auroral ovals and polar regions is likely
to be mostly normal through Wednesday with possible moderately depressed
conditions from late Tuesday through early Wednesday. 30 meter long path
propagation from North America to east and southeast Asia after about 2145Z
is likely to be mostly normal with possible moderate degradation on Tuesday
improving to 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 through Wednesday with
possible moderately depressed conditions from late Tuesday through early
Wednesday. 20 meter transpolar propagation within a few hours of sunrise
and sunset is likely to be mostly normal through Wednesday with possible
moderately depressed conditions from late Tuesday through early Wednesday.

17 and 15 meter long distance propagation is likely to be mostly normal
through Wednesday with possible moderately depressed conditions from late
Tuesday through early Wednesday.

12 and 10 meter long distance propagation is likely to be mostly normal
through Wednesday with possible moderately depressed conditions from late
Tuesday through early Wednesday. 12 and 10 meter long path propagation from
North America to east Asia from about 1200Z to 1400Z is likely to be normal
through 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).

6 meter trans-Atlantic F2 propagation is not likely through at least
Wednesday because of depressed F2 MUFs due to reduced ionizing solar flux.
There is a slight chance of trans-equatorial F2 propagation (TEP) and
oblique-TEP from the southern tier of U.S. states mostly to equatorial
Africa and CQ Zone 32 through at least Wednesday during mid-afternoon and
early evening at the path mid-point. There is a possibility of TEP from the
southern tier of U.S. states to South America and a chance that stations at
mid-latitudes may briefly couple into both TEP and oblique-TEP via possible
intervals of mid-latitude sporadic-E propagation. See K6MIO’s excellent
article on 6 meter TEP, oblique-TEP, TEP-related and mid-latitude
sporadic-E coupling to TEP 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
and a slight chance of isolated strong X-class flares due to two active
regions on the visible disk capable of producing strong flares.

Solar wind parameters are likely to be mildly enhanced through Wednesday
with possible moderately enhanced solar wind from late Tuesday through
early Wednesday due to coronal hole high speed stream effects and possible
CME influence.

Geomagnetic activity is likely to be quiet to unsettled through Wednesday
with possible active intervals and a slight chance of isolated minor
geomagnetic storms from late Tuesday through early Wednesday due to coronal
hole high speed stream effects and possible mild CME influence.

Mid-latitude northern hemisphere sunset is 31 minutes later and day length
is 33 minutes longer than it was on December 21st.

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