[RSM] W3LPL prop forecast thru Tuesday, May 30

[Art Boyars]

(I've missed a few days with QRL and QRT.  I hope to be back on a normal
schedule for a while. -- Art K3KU/VE4VTR)


From: Frank W3LPL <donovanf at starpower.net>
To: PVRC <pvrc at mailman.qth.net>
Cc:
Bcc:
Date: Mon, 29 May 2023 02:04:15 -0400 (EDT)
Subject: [PVRC] Propagation is likely to be normal at low and mid latitudes
and mostly normal at high latitudes with a chance of mildly degraded
intervals at high latitudes during local nighttime hours through midday
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 mildly degraded intervals during local
nighttime hours through midday 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.
Mid-latitude northern hemisphere sunset is 66 minutes later and day length
is 151 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 in the F2
region over Canada above 48 degrees north latitude.

The May 28th Estimated International Sunspot Number was 151. Today's Solar
Flux Index (SFI) is 151 and likely to remain about the same through
Tuesday. The sun’s visible disk has one very large, two large, two medium
and two tiny active regions containing 49 sunspots with a total sunspot
area of 1540 micro-hemispheres (about eight times the surface area of the
Earth). https://www.sidc.be/spaceweatherservices/applications/solarmap

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

The solar wind is lightly enhanced at about 400 km/second, gradually
increasing to moderately enhanced at about 500 km/second or less by late
Monday due to coronal hole high speed stream effects. The solar wind is
likely to be lightly enhanced at about 400 km/second during Tuesday.

Geomagnetic activity is likely to unsettled to active through late Monday
gradually improving to quiet to unsettled by early Tuesday. There is a
chance of isolated active geomagnetic conditions through early Tuesday due
to waning 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 at about
0000Z is likely to be mostly normal through Tuesday. Short path propagation
from North America to east Asia after about 0930Z is likely to be normal on
Monday and mostly normal on Tuesday.

30 meter propagation through the auroral ovals and polar regions is likely
to be mostly normal 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 through Tuesday. 20
meter transpolar propagation within a few hours of sunrise and sunset is
likely to mostly normal through Tuesday.

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

12 and 10 meter long distance propagation is likely to be mostly normal
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
east Asia from about 1200Z to 1400Z is likely to be normal through Tuesday.

6 meter long distance sporadic-E propagation up to 10,000 km or more occurs
daily in the northern hemisphere from early morning through evening hours
until at least mid-July, but its duration and geographic location is highly
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 chance through Tuesday of 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 slight chance through Tuesday of propagation via the
northern equatorial ionization anomaly from the southern tier of US states
to equatorial Africa during mid-afternoon.  There is a slight chance
through Tuesday of oblique-TEP to the south Pacific and VK/ZL during late
afternoon and early evening through Tuesday. There is a slight chance that
stations in the lower 48 U.S. states may briefly couple into TEP and
oblique-TEP via brief geographically focused intervals of mid-latitude
sporadic-E or enhanced F2 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

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
faster than 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