[RSM] W3LPL forecast thru Friday, July 14

[Art Boyars]

From: Frank Donovan <donovanf at starpower.net>
To: PVRC <pvrc at mailman.qth.net>
Cc:
Bcc:
Date: Thu, 13 Jul 2023 03:12:14 -0400 (EDT)
Subject: [PVRC] Propagation is likely to be normal through midday Friday
then mildly degrading through late 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 latitudes is likely to be normal through Friday.
Propagation crossing mid-latitudes is likely to be normal through midday
Friday then mildly degrading through late Friday.   Propagation crossing
the auroral ovals and polar regions is likely to be normal through midday
Friday then degrading to mostly normal through late Friday.
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  Near real time maps and data
about ionospheric conditions are available at prop.kc2g.com
<http://www.prop.kc2g.com/>

Mid-latitude northern hemisphere sunrise is 11 minutes later and sunset is
three minutes earlier 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 north of 45 degrees north latitude.

Today’s Estimated International Sunspot Number is 147 and is likely to
remain about the same through Friday. The sun’s visible disk has two very
large, one large, three medium and six tiny active regions containing 99
sunspots with a total sunspot area of 2140 micro-hemispheres (about 12
times the surface area of the Earth).
https://www.sidc.be/spaceweatherservices/applications/solarmap

Minor to moderate daytime radio blackouts caused by M-class solar flares
are likely through Friday. There is a slight chance of strong daytime radio
blackouts caused by X-class solar flares through Friday.

The solar wind is likely to remain at background levels of about 350
km/second or less through midday Friday, possibly increasing to moderately
elevated levels of about 450 km/second by midday Friday due to weak coronal
hole high speed stream effects and a chance of a glancing blow by a CME.

Geomagnetic activity is likely to be mostly quiet through midday Friday
degrading to unsettled to active with a slight chance of an isolated minor
geomagnetic storm through late Friday due to weak coronal hole high speed
stream effects and a chance of a glancing blow by a CME.
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 after
0000Z is likely to be normal early Friday. Short path propagation from
North America to east Asia after about 0930Z is likely to be normal through
Friday.
30 meter propagation through the auroral ovals and polar regions is likely
to be normal through midday Friday degrading to mostly normal through late
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 normal through midday Friday degrading to
mostly normal through late Friday. 20 meter transpolar propagation within a
few hours of sunrise and sunset is likely to be normal through midday
Friday degrading to mostly normal through late Friday. 20 meter long
distance propagation at low and mid latitudes in the northern hemisphere is
usually degraded from a few hours after sunrise until a few hours before
sunset from June through August by E region and sporadic-E blanketing of
long distance low angle F2 propagation.

17 and 15 meter long distance propagation is likely to be normal through
midday Friday degrading to mostly normal through late Friday. 17 and 15
meter long path propagation from North America to east Asia from about
1200Z to 1400Z is likely to be normal through Friday.

12 and 10 meter long distance propagation is likely to be normal through
midday Friday degrading to mostly normal through late 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 late September. 12 and 10
meter long path propagation from North America to western Australia from
about 1200Z to 1400Z is likely to be normal through Friday.

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 but its duration and geographic extent will become more sporadic and
unpredictable after mid July. 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 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

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