[RSM] W3LPL: Heading down, going into Friday

[Art Boyars]

From: Frank W3LPL <donovanf at starpower.net>
To: PVRC <pvrc at mailman.qth.net>
Cc:
Bcc:
Date: Thu, 16 Feb 2023 04:09:46 -0500 (EST)
Subject: [PVRC] Mostly normal propagation is likely degrading to mostly
below normal by late Friday

FT8WW sunrise is at 0148Z and sunset is at 1544Z.

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 Friday.

Propagation crossing mid-latitudes is likely to be normal degrading to
mostly normal by late Friday.

Propagation crossing the auroral ovals and polar regions is likely to be
normal degrading to mostly below normal by late Friday.

Click *here* <https://services.swpc.noaa.gov/images/station-k-index.png>
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 February 16th daily Estimated International Sunspot Number is 109.
Today's solar flux index (SFI) is 174 and is likely to remain about the
same through Friday. The sun’s visible disk has three large, two medium and
five tiny active regions containing 40 sunspots with a total sunspot area
of 1260 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 Friday.

40 meter short path propagation from North America to south Asia at about
0000Z is likely to be normal degrading to mostly below normal by late
Friday. Short path propagation from North America to east Asia after about
0815Z is likely to be normal through Friday. 40 meter long path propagation
from North America to east and southeast Asia at about 2200Z is likely to
be normal degrading to mostly below normal on Friday.

30 meter propagation through the auroral ovals and polar regions is likely
to be normal degrading to mostly below normal by late Friday. 30 meter long
path propagation from North America to east and southeast Asia at about
2200Z is likely to be normal degrading to mostly below normal on Friday. 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 normal degrading to mostly below normal
by late Friday. 20 meter transpolar propagation within a few hours of
sunrise and sunset is likely to be normal degrading to mostly below normal
by late Friday.

17 and 15 meter long distance propagation is likely to be normal degrading
to mostly below normal by late Friday.

12 and 10 meter long distance propagation is likely to be normal degrading
to mostly below normal by late Friday. 12 and 10 meter long path
propagation from North America to east Asia from about 1200Z to 1400Z is
likely to be normal through Friday. 12 and 10 meter F2 propagation crossing
northern hemisphere mid-latitudes is likely to be enhanced when the solar
flux index is above 120 and geomagnetic activity is quiet to unsettled (K
index of 3 or less).

There is a slight chance through Friday of trans-equatorial F2 propagation
(TEP) from the southern tier of U.S. states to South America from
mid-afternoon through late evening. There is a lesser chance through Friday
of oblique-TEP from the southern tier of U.S. states to CQ Zone 32 and
VK/ZL during mid-afternoon and early evening in the U.S. There is a lesser
chance that U.S. stations at mid-latitudes may briefly couple into both TEP
and oblique-TEP via brief isolated 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 linking 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 mild to moderate daytime radio blackouts caused by
X-ray radiation from strong M-class solar flares through Friday. There is a
slight chance of strong daytime radio blackouts caused by X-ray radiation
from X-class solar flares through Friday.

Solar wind parameters are likely to be mildly elevated degrading to
moderately elevated by late Friday due to possible CME effects.

Geomagnetic activity is likely to be quiet to unsettled with a chance of
isolated active to minor storm levels through late Friday degrading to
active to minor storm levels with a chance on moderate storm levels late
Friday.

Mid-latitude northern hemisphere sunset is 57 minutes later and day length
is 82 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