[RSM] W3LPL: Forecast thru Tuesday, May 2

Mon May 1 01:26:11 EDT 2023

From: Frank W3LPL <donovanf at starpower.net>
To: PVRC <pvrc at mailman.qth.net>
Cc:
Bcc:
Date: Mon, 1 May 2023 01:16:08 -0400 (EDT)
Subject: [PVRC] Propagation is likely to be normal at low and mid-latitudes
and mostly normal at high latitudes through Tuesday. There is a slight
chance of mild to moderate degradations at high latitudes mostly during
local night time hours through Tuesday

See my May QST article "Experience the Wonder's of Solar Cycle 25's Solar
Maximum"     http://www.arrl.org/qst

 My propagation forecast derived from today's NOAA/SWPC web pages and
twelve other online sources (the URLs are included this forecast)
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 normal through
Tuesday.

Propagation crossing the auroral ovals and polar regions is likely to be
mostly normal through Tuesday. There is a slight chance of mild to moderate
degradations at high latitudes mostly during local night time hours through
Tuesday.

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

NWRA’s Table of Space Weather Indices is updated 40 minutes after every
hour at https://spawx.nwra.com/spawx/env_latest.html SILSO’s Estimated
International Sunspot Number is updated continuously at
https://www.sidc.be/silso/DATA/EISN/EISNcurrent.png

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 41 minutes later and day length
is 102 minutes longer than it was on March 20th. Sunrise is about two hours
earlier and sunset is about two hours later at the 300 km altitude of the
F2 region than it is at ground level.

The May 1st Estimated International Sunspot Number is 89. Today's Solar
Flux Index (SFI) is 154 and likely to be about the same through Tuesday.
The sun’s visible disk has one very large, two medium and three tiny active
regions containing 45 sunspots with a total sunspot area of 850
micro-hemispheres (about four times the surface area of the Earth).
https://www.sidc.be/spaceweatherservices/applications/solarmap

There is a chance of minor to moderate radio blackouts on the daylight side
of the Earth caused by M-class solar flares through Tuesday.

The solar wind is likely to be strongly elevated at about 500
km/second through Tuesday as a result of waning coronal hole high speed
stream effects and possible CME influence.

Geomagnetic activity is likely to be quiet to unsettled through mid-day
Tuesday as a result of waning coronal hole high speed stream effects. There
is a chance of active geomagnetic activity with a slight chance of a brief
minor geomagnetic storm after mid-day Tuesday as a result of coronal hole
high speed stream effects and CME influence.

160 and 80 meter propagation from North America to VK/ZL and
the South Pacific is likely to be normal through Tuesday.

40 meter short path propagation from North America to south Asia at about
0000Z is likely to be mostly normal with a slight chance of moderate
degradations through Tuesday. Short path propagation from North America to
east Asia after about 0930Z is likely to be mostly normal with a slight
chance moderate degradations through Tuesday.

30 meter propagation through the auroral ovals and polar regions is likely
to be mostly normal with a slight chance of moderate degradations through
Tuesday. 30 meter propagation is always mildly to moderately degraded
within a few hours of local noon by E-region blanketing of long distance
low angle F2 propagation.

20 meter daytime and evening propagation through the auroral ovals
and polar regions is likely to be mostly normal with a slight chance of
moderate degradations during local night time hours through Tuesday. 20
meter transpolar propagation within a few hours of sunrise and sunset is
likely to be mostly normal with a slight chance of moderate degradations
during local night time hours through Tuesday.

17 and 15 meter long distance propagation is likely to be mostly normal
through Tuesday. 17 and 15 meter long path propagation from North America
to east Asia from about 1200Z to 1400Z is likely to be mostly normal
through Tuesday.
12 and 10 meter long distance propagation is likely to be mostly normal
through Tuesday. 12 and 10 meter long distance propagation crossing mid and
high latitudes is beginning to experience mild effects of the normal
seasonal decline of F2 region MUFs due to reduced free electron density. 12
and 10 meter long path propagation from North America to east Asia from
about 1200Z to 1400Z is likely to be mostly normal through Tuesday. 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 Tuesday of 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 lesser chance through Tuesday of
oblique-TEP from the southern tier and western U.S. to VK/ZL and the south
Pacific from late afternoon through early evening. There is a slight chance
that stations at mid-latitudes in the U.S. may briefly couple into TEP via
brief geographically focused intervals of mid-latitude sporadic-E
propagation. TEP may be enhanced during strong to severe geomagnetic
storms. See K6MIO’s excellnt 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 CME faster than
500 km/second.

Real time geomagnetic data including Bz orientation, IMF field strength,
solar wind speed and short term k-index forecast are available at
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

<http://www.avg.com/email-signature?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail>
Virus-free.www.avg.com
<http://www.avg.com/email-signature?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail>
<#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>