Propagation News – 6 December 2015

Last weekend saw reasonably settled conditions for the CQ Worldwide contest, with DX to be had on all the upper HF bands. However, 10 metres was a little lacklustre this year due to the lower solar flux index compared with 2014.

Twenty and 15 metres proved to be the ‘money bands’ as the flux dipped below 100. Both bands managed to remain open, even giving DX contacts on 14MHz after sunset to countries like Costa Rica, with Mark, M0DXR’s activity at TI5W.

This week has seen more unsettled geomagnetic conditions with the K-index hitting five on Monday due to an elevated solar wind stream. This had a southward-facing Bz component that more easily coupled to the Earth’s magnetic field. We should see the solar flux index in the 90-115 range and we also expect to experience continued unsettled geomagnetic conditions, with the K-index hitting three or four at times. This may impact the higher HF bands, but as we are heading towards the winter solstice our advice is to concentrate on the lower bands, meaning 40, 80 and 160 metres, where you may get some surprises. Forty metres in particular may start to open to DX before sunset, tending towards longer skip as night progresses.

VHF and up propagation news

There was good tropospheric conditions for the 2m UKAC last week, and there is still a chance of improved tropo conditions in time for the 70cm UKAC on Tuesday evening.

The majority of the Continent will be under a large area of high pressure, with good tropo prospects, especially across the Mediterranean and across Biscay down past Spain and Portugal to the Canaries.

Southern Britain, to the south of the weather front, may be able to tap into these better conditions, especially in the first part of the week.

For this tropo action remember to keep to paths south of the weather front. Beaming into northern Europe may be good. Once the front moves away to the south and the weather turns brighter and colder again, you will no longer be in the tropo ducting region. It’s worth checking the forecast maps during the week for signs of the high rebuilding towards southern areas.

The Geminids meteor shower peaks next Sunday, the 13th, so be prepared for some good meteor scatter QSOs next weekend.

Moon declination is negative all this week, so there are short moon windows and low elevation paths. The Moon is very close to the sun next Friday, meaning high noise levels and losses are at maximum on Saturday due to it reaching its apogee, the furthest point from Earth.

Category: GB2RS Propagation News