The solar flux index followed the
NOAA prediction this week, declining to 85 by Thursday. Geomagnetic conditions
were regrettably not as settled as we would have liked, with the K-index hitting
three at times thanks to a continued high speed solar wind stream from a coronal
hole. Luckily, no Earth-directed coronal mass ejections were observed and there
were no major solar flares.
This weekend, and early next week,
NOAA predicts geomagnetic conditions will continue to be unsettled, with a
maximum planetary K-index of four at times. Next weekend, the 24th and 25th, may
however be a little more settled.
The Sun is looking fairly spotless
at the moment and the solar flux index is predicted to be a lacklustre 75 to
80.
Band conditions continue to
improve, although maximum usable frequencies are being suppressed by the lack of
sunspots.
The good news is we have the
autumnal equinox this week, and so are at an optimum time for north-south paths
on HF, such as UK to South Africa and South America.
September can also offer some good
opportunities for grey-line propagation on the lower bands around sunrise.
Andy, M0NKR reports 40m has been
good to the Pacific this week. He also worked Ken, T32AZ on East Kiribati on 20
metres, so it is all about being on the right band at the right time.
VHF and up propagation:
Late summer is the classic high
pressure season of the year. Together with early morning mist and fog, there are
plenty of reasons why VHF and UHF tropo should be on your operating
schedule.
At the end of the hot weather last
week, conditions fell off a little, but there were some huge thunderstorms,
which produced rain scatter right down to 1.3 GHz.
This week there will be high
pressure just to the south of Britain and partially over southern areas at
times. This should offer good tropo across the southern half of the country down
to the south over France and Germany overnight as the surface cools.
Daytime heating usually destroys
any surface night-time temperature inversions, which are needed for tropo. The
downside is that there may be a series of lows tracking over the north, which
means winds and rain and no tropo.
It’s the late show for EME
operators in the early part of this week with moonrise in the early evening,
getting later as the week progresses.
Lengthening Moon windows push
moonset out to early afternoon at the end of the week. Lowest losses will occur
early in the week.
The Orionids meteor shower
continues, with no large peak, into November, so continue to look out for
enhanced meteor scatter conditions this coming week.
