Propagation News – 6 October 2019

| October 4, 2019

We had a real mixed bag in terms of HF propagation last week. The middle of the week through to Friday was actually quite good. Peter, G3XJE ran a very comprised 20m WSPR station from the Propagation Studies Committee stand at the National Hamfest and was picked up as far afield as the southern states in the USA. Saturday was a different story though, thanks to a geomagnetic storm that saw the Kp index soar to five. Twenty metres was pretty lousy and WSPR on 30 metres from Newark only returned a few European spots.

The Sun remained spotless last week and HF propagation is again being dominated by geomagnetic disturbances. Next week NOAA has the solar flux stuck at around 68, with zero sunspots.

This Sunday, 6 October, we may see the effects of another coronal hole, with the Kp index predicted to rise to four. Look out for a possible pre-auroral enhancement. This disturbance may be relatively short lived, with the Kp index falling to two for the rest of the week.

There are a number of DXpeditions on at the moment. The A82X and A82Z DXpedition to Liberia may be one of the easier ones to catch, with openings from 06.00 to 08.00 hours on 30m to 15m being favourite. After the slight mid-day D layer absorption lull, openings again occur all afternoon. Keep an eye on the DX Cluster to see where they are operating.

Station A35JT from Tonga may be a little more difficult for average stations, as will ZK3A from the Tokelau Islands, both in the Pacific Ocean. But if you don’t have a beam and a linear amplifier, why not try FT8?

VHF and up

It’s another very unsettled looking set of weather charts for the week to come. They suggest that once again, rain scatter will be the go-to mode on the GHz bands. The hidden message here is that this means low pressure and a general lack of high pressure and temperature inversions for enhanced tropo conditions.

It can sometimes be useful to explore areas of high pressure a bit further away, and in the next week we find a large high resident between the UK and the Azores. A ridge from this high could occasionally just reach out to the south-western corner of the British Isles to give a small chance of tropo paths from southern Ireland, south-west England and South Wales towards Spain and perhaps as far as the Canaries or Azores.

On Saturday, Moon declination reaches minimum so we’ll see an increase in Moon window lengths and peak moon elevation as the week goes on. Apogee is on Thursday, so losses will be high as well. The only plus is that sky noise on VHF is low all week.

There is a flurry of meteor showers this week with the largest, the Draconids, with a zenithal hourly rate of 10, peaking on the 9th. This is followed by the Southern Taurids on the 10th and the delta Aurigids on the 11th, so we should see some better meteor scatter conditions.

Category: GB2RS Propagation News