[RSM] W3LPL forecast thru Tuesday, June 27

[Art Boyars]

From: Frank W3LPL <donovanf at starpower.net>
To: PVRC <pvrc at mailman.qth.net>
Cc:
Bcc:
Date: Mon, 26 Jun 2023 01:57:29 -0400 (EDT)
Subject: [PVRC] 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 with a chance of mild degradations
primarily during local night time hours through Tuesday

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 with a chance of mild degradations 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.  prop.kc2g.com
<http://www.prop.kc2g.com/> provides
near-real time maps and data about ionospheric conditions.

Mid-latitude northern hemisphere sunset is one minute later and day length
is one minute shorter than it was on June 21st. 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 122 and is likely to be
about the same through Tuesday. The sun’s visible disk has one very large,
one large, two medium and nine tiny active regions containing 50 sunspots
with a total sunspot area of 890 micro-hemispheres (about five times the
surface area of the Earth).
https://www.sidc.be/spaceweatherservices/applications/solarmap

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

The solar wind is likely to decline to mildly enhanced at about 400
km/second during Monday, increasing to moderately enhanced at about 450
km/second or more through Tuesday.

Geomagnetic activity is likely to be mostly quiet with isolated unsettled
intervals during Monday. There is an increasing chance of active
geomagnetic conditions and a slight chance of a minor geomagnetic storm on
Tuesday caused by coronal hole high speed stream effects.

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 after
0000Z is likely to be mostly normal with a chance of mild degradations
primarily during local night time hours through Tuesday. Short path
propagation from North America to east Asia after about 0930Z is likely to
be mostly normal with a chance of mild degradations through Tuesday.

30 meter propagation through the auroral ovals and polar regions is likely
to be mostly normal with a chance of mild degradations primarily during
local night time hours 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 chance of mild
degradations primarily 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 chance of mild degradations primarily
during local night time hours through Tuesday. 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
with a chance of mild degradations primarily during local night time hours
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
with a chance of mild degradations primarily during local night time hours
through Tuesday. 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 Tuesday.

6 meter long distance sporadic-E propagation up to 10,000 km occasionally
occurs 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 Tuesday 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 Tuesday 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 Tuesday of brief
isolated oblique-TEP to the south Pacific and VK/ZL during late afternoon
and early evening through Tuesday. 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 solar
flares and 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