[RSM] W3LPL forecast thru Friday, June 23

[Art Boyars]

From: Frank W3LPL <donovanf at starpower.net>
To: PVRC <pvrc at mailman.qth.net>
Cc:
Bcc:
Date: Thu, 22 Jun 2023 02:05:30 -0400 (EDT)
Subject: [PVRC] Propagation is likely to be normal at low and mid and
latitudes. Propagation crossing the auroral ovals and polar regions is
likely to be mostly normal with a chance of moderate degradations primarily
during local night time hours after midday 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 the auroral ovals and polar regions is likely to be
mostly normal with a chance of mild degradations during local night time
hours through early 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.  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 the same as 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.

The June 21st Estimated International Sunspot Number was 219 and is likely
to be about the same through Friday. The sun’s visible disk has three
large, seven medium and one tiny active region containing 80 sunspots with
a total sunspot area of 1290 micro-hemispheres (about seven 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 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 be mildly enhanced at less than 400 km/second
through midday Friday, increasing to moderately enhanced at 450 km/second
or more after midday Friday.

Geomagnetic activity is likely to be quiet to unsettled with a slight
chance of isolated active intervals through midday Friday. There is an
increasing chance of active geomagnetic conditions and a slight chance of a
minor geomagnetic storm after midday Friday caused by potential CME effects
associated with Tuesday’s X-class solar flare.

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 mostly normal with a chance of moderate degradations
primarily during local night time hours after midday 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 with a chance of moderate degradations primarily during
local night time hours after midday 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 with a chance of moderate
degradations primarily during local night time hours after midday Friday.
20 meter transpolar propagation within a few hours of sunrise and sunset is
likely to be mostly normal with a chance of moderate degradations primarily
during local night time hours after midday 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
with a chance of moderate degradations primarily during local night time
hours after midday 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.

12 and 10 meter long distance propagation is likely to be mostly normal
with a chance of moderate degradations primarily during local night time
hours after midday 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 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 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

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