[RSM] W3LPL: Forecast thru Friday/31

[Art Boyars]

From: Frank W3LPL <donovanf at starpower.net>
To: PVRC <pvrc at mailman.qth.net>
Cc:
Bcc:
Date: Thu, 30 Mar 2023 01:20:06 -0400 (EDT)
Subject: [PVRC] Propagation is likely to be normal at low latitudes and
mostly normal at mid-latitudes through Friday. Propagation is likely to be
mostly normal with mildly degraded periods at high latitudes through Friday

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 mostly normal through
Friday.

Propagation crossing the auroral ovals and polar regions is likely to be
mostly normal with mildly degraded periods through Friday.

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 10 minutes later and day length
is 25 minutes longer than it was on March 20th.

The March 30th daily Estimated International Sunspot Number is 120. Today's
solar flux index (SFI) is 148 and is likely to remain about the same on
Friday. The sun’s visible disk has one large, four medium and five tiny
active regions containing 35 sunspots with a total sunspot area of 560
micro-hemispheres (aboutthree times the surface area of the Earth).
https://www.sidc.be/spaceweatherservices/applications/solarmap

There is a chance of moderate radio blackouts on the daylight side of the
earth caused by M-class solar flares through Thursday.

The solar wind is moderately elevated at about 500 km/second continuing
through mid-day Thursday, then increasing to moderate to high levels
through late Friday.

Geomagnetic activity is likely to be mostly unsettled through mid-day
Thursday, mostly active through early Friday, then unsettled to active
through late Friday 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 normal through Friday.

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

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

17 and 15 meter long distance propagation is likely to be mostly
normal with mildly degraded periods through Friday.

12 and 10 meter long distance propagation is likely to be mostly normal
with mildly degraded periods through Friday. 12 and 10 meter long path
propagation from North America to east Asia from about 1200Z to 1400Z is
likely to mostly normal with mildly degraded periods 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 chance through Friday 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 Friday
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/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