Propagation News – 8 May 2016

The solar flux index held steadfast at 90 for most of the week, but geomagnetic conditions remained unsettled with the K-index hitting five on Bank Holiday Monday. The latter half of the week was a little more settled, bringing better HF conditions with only a few minor C-class solar flares.

At the time of writing, a new large sunspot, number 2542, was just rotating around the sun’s limb. This will join the much smaller sunspot groups that are already visible on the solar disk. As a result, NOAA is predicting the solar flux index could rise to 110 on Sunday, before declining to 95 towards the end of the week.

Geomagnetic conditions will remain unsettled, with the K-index forecast to peak at five on Wednesday 11th.

The Propagation Studies Committee is pleased to announce the next phase of its experimental HF online prediction system is now available for testing. Codenamed Proppy, it can now provide point-to-point predictions as well as area coverage maps. The system uses the new ITURHFProp engine. The site and software is experimental and the ultimate goal is to move the system on to the RSGB website.

VHF and up propagation news

Next week’s weather will be driven by low pressure to the south of Britain and a high over Scandinavia and later near the Faroes. This could mean a little tropo from the east coast to Denmark and southern Sweden, but the rest of the country will be influenced more by low pressure and hence a rather showery type of weather is expected, with the chance of some rain scatter on the GHz bands. Later in the week the low pressure will probably drift east allowing a new high to build from Greenland towards the Faroes.

As a general rule, as we approach summer, rain scatter tends to improve due to more intense rain cells at a more helpful height for propagation.

There have been several separate sporadic-E openings up to 6m within Europe recently, with some reachable from the UK. We are hoping for more this week, but the jet stream pattern is less favourable. More likely areas for the sporadic-E are well south over Iberia and the Mediterranean plus to the north over the Faroes towards Iceland.

For EME operators, the Moon’s declination reaches maximum on Monday and losses are low, so it’s another good week with long afternoon and evening moon windows.

Category: GB2RS Propagation News