[RSM] W3LPL forecast thru Wed/21

Tue Jun 20 17:20:41 EDT 2023

(Busy day.  Did not get a chance to post this until now. -- Art)

From: Frank W3LPL <donovanf at starpower.net>
To: PVRC <pvrc at mailman.qth.net>
Cc:
Bcc:
Date: Tue, 20 Jun 2023 02:24:25 -0400 (EDT)
Subject: [PVRC] Propagation is likely to be normal at low latitudes and
mostly normal at mid and high latitudes with a chance of moderate
degradations primarily during local night time hours through Wednesday

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 latitudes is likely to be normal through Wednesday.

Propagation crossing mid-latitudes, the auroral ovals and polar regions is
likely to be mostly normal with a possibility of mild degradations during
local night time hours through early Wednesday.

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

SWPC’s estimated planetary Kp Index is updated every three hours at
https://services.swpc.noaa.gov/images/station-k-index.png

N0NBH’s current HF Band Conditions report is updated regularly at
https://www.hamqsl.com/solar.html   prop.kc2g.com
<http://www.prop.kc2g.com/> provides near-real time maps and data about
ionospheric conditions.

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 151 and is likely to be
about the same through Wednesday. The sun’s visible disk has two large,
five medium and four tiny active regions containing 71 sunspots with a
total sunspot area of 850 micro-hemispheres (about five times the surface
area of the Earth).
https://www.sidc.be/spaceweatherservices/applications/solarmap

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

The solar wind is likely to be enhanced at about 400 km/second through
Wednesday.

Geomagnetic activity is likely to be mostly unsettled with to active
intervals through Wednesday.  There is a slight chance of moderately
degraded intervals due to minor geomagnetic storms through Wednesday.

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

40 meter short path propagation from North America to south Asia after
0000Z is likely to be mostly normal during local night time hours through
late Wednesday. Short path propagation from North America to east Asia
after about 0930Z is likely to be mostly normal with a slight chance of
moderately degraded intervals due to a chance of minor geomagnetic storms
through Wednesday.

30 meter propagation through the auroral ovals and polar regions is likely
to be mostly normal with a possible moderately degraded intervals primarily
during local night time hours through early Wednesday. 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 nd polar
regions is likely to be mostly normal with a chance of moderately degraded
intervals primarily during local night time hours due to possible minor
geomagnetic storms through Wednesday. 20 meter transpolar propagation
within a few hours of sunrise and sunset is likely to be mostly normal with
a chance of moderately degraded intervals primarily during local night time
hours due to possible minor geomagnetic storms through Wednesday. 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 moderately degraded intervals primarily during local night
time hours due to possible minor geomagnetic storms through Wednesday. 17
and 15 meter long path propagation from North America to east Asia from
about 1200Z to 1400Z is likely to be mostly normal with a chance of mildly
degraded intervals primarily during night time hours due to possible minor
geomagnetic storms through Wednesday.

12 and 10 meter long distance propagation is likely to be mostly normal
with a chance of moderately degraded intervals primarily during night time
hours due to possible minor geomagnetic storms through Wednesday. 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 with a chance of
moderately degraded intervals primarily during night time hours due to
possible minor geomagnetic storms through Wednesday.

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 Wednesday 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 Wednesday 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 Wednesday of brief
isolated oblique-TEP to the south Pacific and VK/ZL during late afternoon
and early evening through Wednesday. 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

The Penticton 10.7 cm solar flux index is updated daily at 1700, 2000 and
2300Z at
https://www.spaceweather.gc.ca/forecast-prevision/solar-solaire/solarflux/sx-5-flux-en.php

Today's three-day GFZ Planetary K Index forecast is updated every three
hours at
https://spaceweather.gfz-potsdam.de/fileadmin/ruggero/Kp_forecast/forecast_figures/KP_FORECAST_CURRENT.png

Today's SIDC Daily Bulletin on Solar and Geomagnetic Activity is updated
daily at 1230Z at
https://www.sidc.be/spaceweatherservices/data/ClassicalRWCproducts/meu

Today's SWPC Solar Activity Forecast Discussion is updated daily at 0030Z
and 1230Z at https://www.swpc.noaa.gov/products/forecast-discussion

Today's Australian Space Forecast Centre Summary and Forecast is updated
daily at 2330Z at https://www.sws.bom.gov.au/Space_Weather/1/1

Perhaps the most useful HF propagation pages for DXers can be found at:
http://dx.qsl.net/propagation and https://www.solarham.net