Friday, November 29, 2024

Propagation update from the U.K.

 

RSGB
GB2RS News Team
November 29, 2024

Last weekend’s CQWW CW contest was a reminder of just how good HF
propagation can be near sunspot maximum.

The whole world was workable on the contest bands up to 10 metres,
including the Far East, Australasia, the Caribbean and South America. It
was a great opportunity to increase your DXCC total and have fun at the
same time.

This week’s solar flux index crept back above 200 again, peaking at 225
as this report was being prepared. Geomagnetic conditions have been
surprisingly good over the past seven days with a peak Kp index of 3.67
on the 24 November.

There have been no X-class solar flares, but there has been a total of
13 M-class and 54 minor C-class flares over the past seven days. There
have been coronal mass ejections, notably on the 25 November, but they
have not been Earth-directed as of the 28 November.

So, to summarise, HF conditions have been pretty good.

We are now entering the Winter period for HF propagation, which tends to
favour the low bands. So 160m, 80m and 40m come into their own and
night-time DXing becomes the norm. Look for greyline openings to the
west at sunrise on 80m and 160m, and also short, but good, openings on
40m in the late afternoon.

Night-time may bring good DX on 80m and 40m, including the Caribbean and
South America.

NOAA predicts that the SFI will remain in the low 200s next week, and
while geomagnetic conditions are forecast to be good at first, the Kp
index may rise to four on the 4 to 6 December. This could result in
reduced MUFs until the Kp index recovers.

VHF and up :

The unsettled theme continues through most of the next week or two. The
only signs of slightly enhanced prospects for Tropo are as we close this
week, and even that is restricted to some eastern areas for paths across
the North Sea.

A second option may temporarily appear around the middle of the coming
week as a weak high crosses southern areas, but this one looks to be a
cold high and probably not so good as a vehicle for Tropo.

The meteor scatter prospects are aided by the last throes of the Leonids
which fade away by this weekend, and the Orionids which peaked on
Thursday 28 November, but last through the coming week.

The unsettled weather should offer some useful GHz bands rain or snow
scatter, since there will be several active weather systems around. This
early in the winter is a great time for strong shower activity around
the still relatively warmer seas.

The auroral prospects are worth checking after recent activity. Look for
watery-sounding signals on the LF bands as a good clue along with Kp
index values greater than four.

Last week saw some fleeting signs of Sporadic E on the Dourbes ionosonde
graphs on propquest.co.uk, especially on Monday 25 November. This
occurred typically around the middle of the day and was probably driven
by the very strong jet stream and the current meteor activity.

The Moon’s declination is negative, reaching minus 28 degrees on Monday
and we are close to eclipse on Sunday. That’s followed by two days of
high 144MHz sky noise, so with path losses still high, EME operators
should probably take the opportunity to check their antennas after last
week’s gale.

(Mike Terry/BDXC)