venerdì 7 gennaio 2022

Propagation News – 9 January 2022

GB2RS News Team | January 7, 2022
Welcome back to the GB2RS HF Propagation News. And we start the year on a bit of a downer, with the solar flux index back in the 80s. On Thursday the 6th, the SFI was at 84 with two active sunspot regions. This is probably going to be a short-lived lull in solar activity as we know that more active regions are coming back around the Sun in due course.

The Kp index has mainly been low over the past week, reaching a maximum of four on the third, but generally being in the range of zero to three. We may get an elevated Kp index this weekend due to an Earth-facing coronal hole and its associated high-speed solar wind stream.

The big question is what happens next? Will we see a return to those glorious days just before Christmas where the SFI was 140? The likely answer is yes we will, but knowing quite when we will get there is difficult. NOAA predicts that the SFI will climb past 100 on the 12th of January, reaching a maximum of 120 a few days later. Returning active regions 2907 and 2908 should appear at the beginning of the week, but we don’t know just how active they still are.

Meanwhile MUFs over a 3,000km path are reaching 21MHz most days and there are occasional 28MHz openings, especially around lunchtime. So keep an eye on the higher bands, which may spring some surprises, especially with low-signal modes like FT8. And the low bands, such as 160, 80 and 40m are still worth looking at and will continue to be for the next month or so.

Let’s hope we have more positive news next week.

VHF and up:

There have been hints of Sporadic-E recently in digital modes on 10m and 6m, which is quite often seen around this time of the year. There is probably one more week in this window of opportunity before the lean months begin and little activity until well into April. In this case we still have some powerful winter jet streams nearby so that’s one box ticked for Sporadic-E.

Tropo is not likely to feature until after the weekend when we see high pressure building behind a cold front on Sunday. By Tuesday there should be some first signs, initially in the south, but models suggest a more widespread distribution to include northern areas as the high develops during the week.

Keep alert for auroras, and random, non-shower, meteor scatter is always a good banker for some DX. The Quadrantid meteor shower has peaked so we are entering the quiet period for meteor activity until the Lyrids on the 22nd of April.

The Moon has positive declination again, peaking next Sunday, but path losses reach their highest at apogee on Friday. 144MHz sky noise is low but increasing, reaching 500K next Saturday. (rsgb.org)