Propagation News – 7 April 2019

Last week saw more of the same as we head towards solar minimum, which is now expected to be some time in 2020. There was a slight increase in the solar flux index later in the week as a new embryonic sunspot appeared on the visible disk. A group of three solar coronal holes threatened to cause disturbed conditions this weekend and again on the 12th of April, with NOAA predicting the Kp index could rise to four. Otherwise the geomagnetic conditions will remain settled and the solar flux index is forecast to remain at about 69-70.

This is a good time of year for North-South paths, such as the UK to South Africa and UK to South America. Maximum usable frequencies are expected to be about 14 to 18MHz. But don’t ignore 30 and 40 metres, which could still throw up some surprises, especially around sunset. There is a slight chance of openings to Australia and New Zealand on these lower bands and the HF propagation prediction tool at www.predtest.uk will help show you the best times to attempt a contact. Contacts into North Africa are also a possibility on 20-40m, especially in the early evening.

Do make the most of HF at this time as conditions are likely to get worse as we head into summer, apart from the Sporadic-E season, but more of that later.

VHF and up

It’s looking like a finely balanced weather pattern with high pressure to the north of the British Isles and low pressure near to southern areas. The influence is more from low pressure at first, so there is a continuing chance of heavy April showers bringing some rain scatter to the GHz bands, just as we had last week.

As the northern high becomes stronger, it will introduce an easterly or northeasterly weather pattern, so the North Sea coast will feel very chilly. The strong winds at times will mean that Tropo doesn’t get much of a look-in in the south, although there is a possibility in the north. So, the main theme of the VHF/UHF bands will be a possible occasional bit of weak Tropo in the north, plus some rain scatter in the south. Use the online radars to see where the echo points might be.

We are approaching mid April now, so it’s time to start monitoring the 6 and 10m bands for some Sporadic-E. Last week already saw cluster reports of FT8 QSOs so it will be interesting to note how this new mode is extending the Sporadic-E season.

Moon declination is positive and rising and path losses are falling this week, so it’s a good one for EME. There are no significant meteor showers, but we are only a couple of weeks away from the Lyrids on the 23rd.

Category: GB2RS Propagation News