Last week, the solar flux index remained in the mid to high 70s, but HF
propagation was once again dominated by variable geomagnetic conditions. The
first half of the week, which included the CQ Worldwide contest, was very
unsettled with the K index at high latitudes peaking at seven. This drove down
maximum useable frequencies and impacted a lot of potential DX
contacts.
The second half of the week was a little more settled as a
large coronal hole on the sun rotated away, but the K index was still four at
times.
We should now see more settled geomagnetic conditions, at least
until around the 8th or perhaps the 11th, depending upon which model you
believe, when the K index will climb once again.
This is not expected to
have much effect on LF, MF and HF over 2,000 to 3,000km paths, but may cause a
reduction in signal levels particularly on longer, more northerly, paths that
may persist for two or three days.
Otherwise, this is now a prime time
for HF propagation, with worldwide contacts possible on all bands up to around
21MHz, with occasional openings on 12 and even 10 metres.
If you want a
challenge, you still have a few days left to work the Six-Gs groups on Chatham
Island who are operating as ZL7G.
After some welcome Tropo last week, we
start this week with a low pressure system over the North Sea and a showery
northerly across much of the country. Apart from a chance of some rain scatter
on the Gigahertz bands, the VHF/UHF prospects seem likely to be uninspiring at
first.
Soon after the weekend, we should find high pressure building back
in across north-west Britain and this will gradually migrate to southern areas,
leaving space for low pressure and a brisk westerly wind to reach the north
again by the end of the week. During this period, as the high moves south, there
is a prospect of some limited Tropo, especially in the south and across the near
continent.
For meteor scatter enthusiasts, start preparing for the major
shower for this month – the Leonids. It peaks on Thursday, the 17th, at around
1030UTC. Otherwise, it’s back to early mornings for random contacts on the low
VHF bands.
Moon declination is at a minimum today and losses are high,
but reduce as the week progresses, dropping to a minimum next
Sunday.
Moon windows continue to lengthen as declination becomes
positive again.
