[RSM] W3LPL forecast thru Friday/16

Thu Jun 15 15:21:03 EDT 2023

From: Frank W3LPL <donovanf at starpower.net>
To: PVRC <pvrc at mailman.qth.net>
Cc:
Bcc:
Date: Thu, 15 Jun 2023 03:05:36 -0400 (EDT)
Subject: [PVRC] Propagation is likely to be normal at low and mid latitudes
and mostly normal with possible mild degradations at high latitudes during
local night time hours through Friday

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 Friday.

Propagation crossing auroral ovals and polar regions is likely to be mostly
normal with possible mild degradations during local night time hours at
high latitudes through Friday.

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
76 minutes later and day length is 166 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 sun never sets today on the F2 region above 45 degrees north latitude.

Today’s Estimated International Sunspot Number is 109. Today's Solar Flux
Index (SFI) is 144 and is likely to remain about the same through Friday.
The sun’s visible disk has seven medium sized active regions containing 37
sunspots with a total sunspot area of 690 micro-hemispheres (about four
times the surface area of the Earth).
https://www.sidc.be/spaceweatherservices/applications/solarmap

There is a slight chance of isolated minor to moderate daytime radio
blackouts caused by M-class solar flares through Friday.

The solar wind is lightly enhanced at about 370 km/second through midday
Thursday. The solar wind is likely to gradually become moderately enhanced
at about 450 to 500 km/second by midday Friday due to coronal hole high
speed stream effects.

Geomagnetic activity is likely to be mostly quiet through midday Thursday
with possible unsettled conditions through early Friday. Geomagnetic
activity is likely to degrade to mostly unsettled to active through late
Friday with a slight chance of a minor geomagnetic storm during midday
Friday.

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 through Friday. Short path propagation
from North America to east Asia after about 0930Z is likely to be mostly
normal through Friday.

30 meter propagation through the auroral ovals and polar regions is likely
to be mostly normal through Friday. 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 through Friday. 20
meter transpolar propagation within a few hours of sunrise and sunset is
likely to be mostly normal through Friday. 20 meter long distance
propagation at low and mid latitudes in northern hemisphere is usually
degraded during daylight hours from June through September by E region and
sporadic-E blanketing of long distance F2 propagation.

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

12 and 10 meter long distance propagation is likely to be mostly
normal through Friday. 12 and 10 meter long distance propagation crossing
the north Atlantic and north Pacific is degraded by seasonally lower
daytime MUFs due to reduced daytime free electron density in the F2 region
through mid-September. 12 and 10 meter long path propagation from North
America to western Australia from about 1200Z to 1400Z is likely to be
mostly normal through Friday.

6 meter long distance sporadic-E propagation up to 10,000 km and
occasionally more occurs daily in the northern hemisphere from early
morning through late evening hours through at least mid-July, but its
duration and geographic extent is both sporadic and unpredictable. See
K6MIO’s excellent article about 6 meter long distance sporadic-E:
www.qsl.net/wa3mej/Articles/Propagation/6M%20Prop/K6MIO/Extreme%20Range%2050-MHz%20Es-%20East%E2%80%93West%20(EWEE).pdf
There is a very slight chance through Friday of brief 6 meter F2
trans-equatorial propagation (TEP) from the southern tier of U.S. states to
South America and the south Atlantic (e.g., ZD7) from early afternoon
through late evening. There is a very slight chance through Friday of brief
isolated propagation via the northern equatorial ionization anomaly from
the southern tier of US states to equatorial Africa during
mid-afternoon.  There is a very slight chance through Friday of brief
isolated oblique-TEP to the south Pacific and VK/ZL during late afternoon
and early evening through Friday. There is a very slight chance that
stations in the lower 48 U.S. states may briefly couple into TEP and
oblique-TEP via geographically focused intervals of mid-latitude sporadic-E
propagation. TEP may be enhanced during the onset of strong to severe
geomagnetic storms then significantly degrading after initial enhancement.
See K6MIO’s excellent article on 6 meter TEP, oblique-TEP, TEP-related and
mid-latitude sporadic-E linking to TEP beginning on page 9 at:
http://www.oh3ac.fi/QEX-2016-11.pdf

We are in the summer solstice season when geomagnetic disturbances are less
severe and occur about half as often as during the equinox seasons.

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 and solar wind
exceeding 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