[RSM] W3LPL: Prop forecast thru Thursday, March 30

[Art Boyars]

From: Frank W3LPL <donovanf at starpower.net>
To: PVRC <pvrc at mailman.qth.net>
Cc:
Bcc:
Date: Wed, 29 Mar 2023 02:22:11 -0400 (EDT)
Subject: [PVRC] Propagation is likely to be above normal at low and
mid-latitudes through mid-day Thursday, then normal through late Thursday.
Propagation is likely to be mostly normal at high latitudes through Thursday

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 and mid-latitudes is likely to be above normal at
low and mid-latitudes through mid-day Thursday, then normal through late
Thursday.

Propagation crossing the auroral ovals and polar regions is likely to be
mostly normal through Thursday.

VE3EN’s End-of-Day Solar Report is published daily at 0045Z at:
https://www.solarham.net

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.
Mid-latitude northern hemisphere sunset is nine minutes later and day
length is 23 minutes longer than it was on March 20th.

The March 29th daily Estimated International Sunspot Number is 131. Today's
solar flux index (SFI) is 159 and is likely to remain about the same on
Thursday. The sun’s visible disk has one large, six medium and one tiny
active regions containing 34 sunspots with a total sunspot area of 860
micro-hemispheres (about four times the surface area of the Earth).
https://www.sidc.be/spaceweatherservices/applications/solarmap

Radio blackouts are not likely through Thursday.

The solar wind is at nominal levels at about 350 km/second through mid-day
Thursday, then degrading to moderately elevated levels through late
Thursday.

Geomagnetic activity is likely to be mostly quiet through mid-day Thursday,
then mostly active through late Thursday due to coronal hole high speed
stream effects. We are in the vernal equinox season when geomagnetic
disturbances are about 50% more likely than during most of the year.

160 and 80 meter propagation from North America to VK/ZL and the
south Pacific is likely to be above normal through mid-day Thursday, then
normal through late Thursday.

40 meter short path propagation from North America to south Asia at about
0000Z is likely to be mostly normal through Thursday. Short path
propagation from North America to east Asia after about 0830Z is likely to
be mostly normal through Thursday. 40 meter long path propagation from
North America to southeast Asia at about 2330Z is likely to be mostly
normal through Thursday.

30 meter propagation through the auroral ovals and polar regions is likely
to be mostly normal through Thursday. 30 meter long path propagation from
North America to southeast Asia at about 2300Z is likely to be mostly
normal through Thursday. 30 meter propagation is always mildly 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 Thursday. 20
meter transpolar propagation within a few hours of sunrise and sunset is
likely to be mostly normal through Thursday.

17 and 15 meter long distance propagation is likely to be mostly normal
through Thursday.

12 and 10 meter long distance propagation is likely to be mostly normal
through Thursday. 12 and 10 meter long path propagation from North America
to east Asia from about 1200Z to 1400Z is likely to normal through
Thursday. 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 chance through Thursday of trans-equatorial F2 trans-equatorial
propagation (TEP) from the southern tier of U.S. states to South America
from early afternoon through late evening. There is a chance through
Thursday of oblique-TEP from the southern tier and western U.S. states to
VK/ZL and the south Pacific during late afternoon and early evening. There
is a lesser chance that U.S. stations at mid-latitudes may coupl into both
TEP and oblique-TEP via brief isolated intervals of mid-latitude sporadic-E
propagation. TEP and oblique-TEP may be enhanced during strong geomagnetic
storms that occur more frequently through late April during the vernal
equinox season. 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 mildly stronger than 5 nanoteslas for several hours
or more coincident with the effects of an Earth directed fast CME (faster
than 700 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:
https://www.swpc.noaa.gov/products/geospace-geomagnetic-activity-plot

Click *here* <https://www.spaceweather.gc.ca/solarflux/sx-4-en.php> for today’s
Penticton 10.7 cm solar flux index updated at 1700Z, 2000Z and 2300Z 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 https://www.solarham.net