[RSM] W3LPL: OK at high latitudes, better at low and mid- thru Wednesday

[Art Boyars]

From: Frank W3LPL <donovanf at starpower.net>
To: PVRC <pvrc at mailman.qth.net>
Cc:
Bcc:
Date: Tue, 28 Mar 2023 02:27:23 -0400 (EDT)
Subject: [PVRC] Propagation is likely to be above normal at low and
mid-latitudes and mostly normal at high latitudes through 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 and mid-latitudes is likely to be above normal
through Wednesday.

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

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 eight minutes later and day
length is 20 minutes longer than it was on March 20th.

The March 28th daily Estimated International Sunspot Number is 119. Today's
solar flux index (SFI) is 158 and is likely to decline slightly on
Wednesday. The sun’s visible disk has one large, five medium and three tiny
active regions containing 38 sunspots with a total sunspot area of 650
micro-hemispheres (about three times the surface area of the Earth).
https://www.sidc.be/spaceweatherservices/applications/solarmap

Radio blackouts are not likely through Wednesday.

Solar wind parameters are slightly to mildly enhanced at about 350
km/second due to waning coronal hole high speed stream effects improving to
nominal levels on Wednesday.

Geomagnetic activity is likely to be mostly quiet to unsettled on Tuesday
with a slight chance of isolated active geomagnetic activity due to waning
coronal hole high speed stream effects, improving to mostly quiet on
Wednesday. 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 Wednesday.

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

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

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

12 and 10 meter long distance propagation is likely to be mostly normal
through Wednesday. 12 and 10 meter long path propagation from North America
to east Asia from about 1200Z to 1400Z is likely to mostly 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 above
120 and geomagnetic activity is quiet to unsettled (K index of 3 or less).

There is a chance through Wednesday 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
Wednesday 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 couple 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