venerdì 2 aprile 2021

Propagation News – 4 April 2021

This last week has certainly been quieter from a geomagnetic disturbance point of view. We have seen the Kp index at one for much of the time, and it even hit zero in the early hours of Tuesday the 30th. We have not been quite so lucky on the sunspot front, with zero spots being recorded on Wednesday.

Nevertheless, 17 metres has provided some good DX paths, especially via FT8, and even 21MHz has opened up at times. The Far East and the Caribbean have been favourites on 17 metres, but a quick scan through 15 metres showed nothing, except for a spike at 21.074MHz where a good sprinkling of European stations, plus Brazil, Saudi Arabia and Israel could be copied.

There have been some North-South paths worked on 10 metres via Trans-Equatorial Propagation or TEP, but these have mainly favoured stations located south of the UK. Coming down to 40 metres, there is always fun to be had contacting Summits on the Air operators, who are always keen to make contacts. SOTA ops in Switzerland, Austria and Germany can usually be worked on CW around 7.032MHz, even with QRP power, no doubt due to their very low noise levels on mountain tops.

Next week NOAA predicts that the solar flux index will remain in the low 70s, with quiet geomagnetic conditions for the first half of the week. From the eighth to the tenth we may expect more disturbed conditions due to the return of another coronal hole. There is also the slim chance of the odd Sporadic-E opening, particularly on 10 metres, but more of that in the next section.

VHF and up:

Conditions in the warm air part of the high pressure have been good with some strong Tropo, especially over England and Wales. The fronts over Scotland and Ireland have prevented any Tropo there, but will weaken by this weekend when we will find the main high centre to the north and west of Britain introducing some chance of temporary Tropo here also. The big change is the development of a dominant low over Scandinavia during this weekend and this will bring strong northerly winds and a return of very cold air with a chance of wintry showers moving south today, Easter Sunday, and Monday. This will potentially be a good time for some rain scatter on the GHz bands. These springtime showers can be sources of hail and thunderstorms, so be ready to track them on the many online radar sites. Conditions remain cold and unsettled for much of the next week.

For Sporadic-E enthusiasts, we are entering the period when the first fleeting openings may make a surprise appearance even for the traditional modes like SSB and CW, so perhaps give 10m a look now and again and possibly 6m too. Obviously, digital modes will potentially be a good early warning sign of activity, or at least the directions of interest.

Moon declination is at minimum today, so peak Moon elevations are at their lowest but will increase as the week progresses. We are past perigee so losses will also increase.

With no significant meteor showers this week, the best time for meteor scatter contacts is the pre-dawn random meteor enhancement. (