[RSM] W3LPL: Mostly normal, but CMEs Wed/Thur

[Art Boyars]

From: donovanf at erols.com

To: PVRC <pvrc at mailman.qth.net>
Cc:
Bcc:
Date: Wed, 3 Nov 2021 01:57:33 -0400 (EDT)
Subject: [PVRC] Mostly normal propagation until of arrival of multiple CMEs
late Wednesday or early 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 normal through
late Wednesday. Coronal hole high speed stream effects combined with
multiple Earth directed CMEs are then likely to result in mostly below
normal propagation through late Thursday.

Propagation crossing the auroral ovals and polar regions is likely to be
mostly normal through late Wednesday. Coronal hole high speed stream
effects combined with multiple Earth directed CMEs are then likely to
result in below normal propagation through late Thursday.

There is a chance that continuing M-class solar flare activity may cause
minor to moderate radio blackouts on the sunlit side of the Earth through
Thursday.

Click *here* <https://services.swpc.noaa.gov/images/planetary-k-index.gif>
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 solar flux index (SFI) is likely to be about 95 through Thursday. There
are three active regions on the visible disk with 12 mostly small and a few
moderate sized sunspots.
https://sdo.gsfc.nasa.gov/assets/img/latest/latest_1024_0171.jpg

160 and 80 meter propagation from North America to VK/ZL and the south
Pacific is likely to be normal on Wednesday and mostly below normal on
Thursday.

40 meter short path propagation from North America to south Asia until
about 0100Z is likely to be below normal through Thursday. 40 meter short
path propagation from North America to east Asia after about 0800Z is
likely to be mostly normal on Wednesday and below normal on Thursday.

30 meter propagation through the auroral ovals and polar regions is likely
to be mostly normal through late Wednesday, then mostly below normal
through late Thursday. 30 meter propagation is always significantly
degraded within a few hours of local noon because of 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 late Wednesday, then
mostly below normal through late Thursday. 20 meter transpolar propagation
within a few hours of sunrise and sunset is likely to be below normal from
late Wednesday through late Thursday.

 17, 15, 12 and 10 meter long distance propagation is likely to be mostly
normal through late Wednesday, then mostly below normal through late
Thursday. Long path propagation is likely starting a few hours after
sunrise on Wednesday and persisting for several hours but is less likely to
occur on Thursday.

Geomagnetic disturbances *caused by CME and coronal hole* *high speed
stream* effects are likely to remain mostly brief, minor and somewhat less
frequent through at least late 2021. 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
enhanced IMF field strength 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 enhanced IMF field strength for several hours or
more *coincident with* the effects of an Earth directed fast CME.

Real time geomagnetic data including Bz orientation are available here:
www.swpc.noaa.gov/products/geospace-geomagnetic-activity-plot

The solar wind is likely to be enhanced through Thursday but with moderately
disturbed intervals from late Wednesday through late Thursday.

The geomagnetic field is likely to be quiet with possible unsettled intervals
through late Wednesday after which coronal hole high speed stream effects
combined with multiple Earth directed CMEs are likely to result in minor
geomagnetic storm activity with a chance of isolated moderate geomagnetic
storm intervals through mid day Thursday.

Mid-latitude northern hemisphere sunset is 59 minutes earlier and daylength
is 101 minutes shorter than it was on September 22nd. Daytime ionization
and residual nighttime ionization in the northern polar region is rapidly
declining due to steadily increasing polar night effects.

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 http://www.solarham.net