Propagation News – 13 March 2022

| March 11, 2022

We may not have had a large number of sunspots this week, but at least the Sun was consistent. We started the week last Sunday with a sunspot number of 116, and by Thursday it was still at 115. This sounds worse than it actually was as there were six sunspot groups active on Thursday, including newly-assigned active region 2965, which is turning into view off the east limb.

As we predicted, last weekend was characterised by unsettled geomagnetic conditions with a maximum Kp index of five across Saturday and Sunday. This affected HF a little, but there were still some good UK scores put in for the ARRL DX International SSB contest, with Andy, M0NKR making 812 contacts in just seven hours on 40, 20 and 15 metres. He also reports working many USA west coast stations on 15 metres, which appeared to be the money band.

NOAA predicts that next week we will have a decline in solar activity with a predicted solar flux index of 110 falling to 100 by the end of the week. From a geomagnetic point of view it may be a repeat of last weekend. NOAA says that it predicts a maximum Kp index of four this weekend, then we may have quieter conditions next week. But then it predicts an elevated Kp index the following weekend (19th to the 21st) of up to four again.

Finally, don’t forget we have the Commonwealth Contest this weekend, which is a great opportunity to work some choice DX stations with no competition from non-Commonwealth entities – this doesn’t happen very often!

VHF and up

This first weekend sees a continuation of the unsettled weather type, especially in western areas, but there is a large area of high pressure just out of reach over central Europe. This looks as though it could edge towards the eastern side of the UK as we move into the new week and may give some Tropo to the east into the Baltic.

The problem is that there is a chance of some much colder air moving in from the east with a chance of some wintry showers, although the main feature is likely to be the strength of the winds, bitterly cold and not really conducive to good Tropo.

The other modes can still play a role, so check the solar data for high K indices, indicating a chance of aurora, as well as the usual early morning random meteor scatter. Perhaps start to dust down your techniques for Sporadic-E as we head into the second half of the month. We are not there yet, but maybe it is worth the occasional look at 10m.

The Moon’s declination is positive until next Saturday, and path losses are falling with perigee still more than a week away. 144MHz sky noise is low all week, creeping to just over 300 Kelvin next weekend.

Category: GB2RS Propagation News