Propagation News – 7 January 2018

Last week the solar flux index (SFI) hovered around the 70 mark, reflecting the lack of sunspots. Given that the SFI doesn’t really fall below about 65-66 at sunspot minimum, this shows the distinct lack of solar activity at this time. This meant that the lower bands were the ones to see the most activity, with 80 and 40 metres showing just how well they can work during the winter. There were reports of the US being worked on 80 metres at sunrise and on 40 metres during late afternoon. Japan was also worked on 40 metres. This month will offer very similar propagation to December on the low bands so make sure you don’t miss it.

There were also reports of sporadic E openings into Europe on the HF bands. Winter sporadic E can often bring strong short-skip openings from 40 up to 10 metres, as well as on the 6m band, as you will hear later.

The SFI is predicted to remain around 70 next week, so expect more of the same, propagation-wise.

Unsettled geomagnetic conditions are forecast for around the seventh and eighth, due to a high-speed solar wind stream from a recurrent coronal hole. The 23th and 14th may also be unsettled, with a possible maximum K-index of five, so look for auroral-type noisy conditions, and depressed maximum usable frequencies after a potential short-lived upswing after the enhanced solar wind hits.

VHF and up

The New Year starts with a hint of tropo promise as high pressure drifts across the north of the country this weekend. Conditions in such winter highs may not always deliver good results and this one could be a bringer of shallow surface inversions with only limited tropo lift potential. This high will soon be replaced by the return of low pressure and more unsettled conditions during next week, so look for rain scatter on the microwave bands.

Last week saw some good 50MHz sporadic E into Europe, mainly from western Britain and one reported path within Europe on 70MHz. This is a timely reminder that, although rare, sporadic E is possible outside of the traditional high summer season, so keep looking!

After last week’s short Quadrantids meteor shower we are entering the annual low in sporadic meteor activity that lasts until the Lyrids shower at the end of April, so you’ll need to work hard for meteor scatter contacts for a while.

Moon declination goes negative on Monday and we are just a week away from its apogee, the point at which the Moon is furthest from the Earth, so EME opportunities will be short and path losses will increase as the week progresses.

Category: GB2RS Propagation News