Propagation News – 6 February 2022

We had another topsy-turvy week, with lots of good sunspots, but coronal mass ejections or CMEs taking their toll on the ionosphere as well. While the solar flux index did a little better than predicted, with numbers in the 120-130 range, there was bad news on the solar-terrestrial front.

The Kp index was regularly hitting four and even five on Thursday, thanks to CMEs, which depressed MUFs considerably. But things could have been a lot worse. NASA issued a major storm warning after the CME on the 29th of January, with newspapers predicting that visible aurora would be seen across the UK. But, in the end, this amounted to very little and the warning was cancelled.

Despite all this geomagnetic activity there were pearls to be found. Contacts with Hong Kong, China and Australia were all reported by members of the 10 metre UK Net Facebook group. As Jack, G8DX wrote on the group: “What an end to the month. ZL, JA, XV, BY, BV, HS, YB on FT8 and 30-plus VKs on phone and a few on CW.”

And bear in mind that this solar cycle has got a lot further to go, with a predicted sunspot number of more than 100 at its peak in 2025/2026. To give you some idea of what that means, this week it was 65.

Next week there may be some good news. NOAA predicts that the solar flux index could rise to 125, and perhaps even higher. As always, we can probably expect unsettled geomagnetic conditions, with the Kp index predicted to hit four on the 10th.

As always, keep an eye on solarham.com for a more accurate day-to-day update as things can change very quickly.

In terms of propagation highlights, look for openings to Sydney, Australia on 10 metres around 8-10am. Short-path openings to Perth may peak a little later.

VHF and up

The present spell of unsettled weather is likely to continue for a while, into the first part of next week, but before that, there are signs of the next high building over southern areas. This will bring a return of Tropo conditions to many areas, although a further low will track across northern Britain towards the end of the week.

As we hinted last week, the high pressure produced some good Tropo DX down across Biscay to Spain and France on 2m through to 23cm. The situation next week is looking similar, so a good week to get some CW and SSB onto 70cm for the UK Activity Contest on Tuesday and see what happens on Thursday for the 6m UKAC.

The other modes to check are, like last week, the pre-dawn random meteor scatter options plus a chance aurora in view of the unsettled solar-terrestrial conditions at the moment.

Moon declination is positive and rising all week, so Moon windows are long and peak Moon elevation high. Path losses are also high as we approach apogee on Friday.

For VHF EMEers, 144MHz sky noise is low to moderate throughout the week, peaking at 500 Kelvin on Friday.

Category: GB2RS Propagation News