Propagation News – 17 April 2016

| April 15, 2016

No sooner did we say that it was beginning to look like the start of a solar minimum than an enormous sunspot appeared around the sun’s limb. Sunspot 2529 has produced a number of B and C-class solar flares. And despite NOAA predicting a solar flux index of around 80 last week, it rocketed to 111.

Geomagnetic conditions remained unsettled all week thanks to coronal hole activity and associated high-speed solar wind streams. The K-index hit five on Wednesday and Friday, and hovered around three and four all week. Next week the solar flux index is predicted to remain around 90-100. Geomagnetic conditions are predicted to be more settled, with perhaps Tuesday the 19th and Saturday the 23rd more unsettled.

Speaking of which, Saturday the 23rd is International Marconi Day, when more than 60 special event stations around the world join in on HF to celebrate the inventor’s birthday. You can get a nice certificate by working 15 of these stations and Steve G0KYA has a set of propagation conditions for UK stations on his Blogspot pageā€”just Google G0KYA.

Eighty and forty metres will be best for working the UK stations, while 20m may be optimum for the Europeans. The East Coast of the USA is more problematic, with 20 or 17m likely to be the best bands.

VHF and up propagation news

This weekend we still have the leftovers of the low pressure and April showers in south-eastern Britain, but high pressure is building in from the west to affect much of the country early next week. This could bring some slightly-enhanced tropo conditions, but only briefly since unsettled showery weather will return after midweek. We therefore have some chance of tropo, mostly west-east paths into northern Europe during the first half of the week, and either side. April showers could give some rain scatter on the gigahertz bands.

There have been a few sporadic-E openings on 10m. One on Wednesday, 13 April, from Austria to Scotland was crossed by a jet stream over the mountains of southern Germany. It is worth checking the RSGB propagation forum for the daily jet stream forecast charts to see which direction the sporadic-E might appear from. Look for jet streams crossing mountain ranges like the Alps or Pyrenees.

The 2016 Lyrids meteor shower peaks on 21 and 22 April so by now we should be seeing a noticeable increase in meteor rates. For EME operators, the Moon is up in the evening and overnight this coming week, but losses are highest as we approach apogee on Thursday.

Category: GB2RS Propagation News