Propagation News – 30 October 2022

| October 28, 2022

Good conditions on HF have continued with only a short geomagnetic disturbance to dull things a little. The planetary Kp index got up to five on the 25th, due to plasma from a geo-effective coronal hole, but luckily it recovered quite quickly. Two days later it was back to one and the upper HF bands came alive again.

The ionosphere was disturbed on 23 and 24 October, with the MUF over a 3,000km path dipping in and out of the 10m band. But by 25 October things were pretty much back to normal.

The solar flux index dropped down to 105 on 22 October but recovered a little to end at 122 on Thursday.

It has once again been a good week for 10m with openings to the US being commonplace. This is a good opportunity to up your Worked All States score with the 14, 18 and 21MHz bands remaining open long after sunset. 28MHz is also shining during daylight hours.

Other notable contacts were AH7C Hawaii on 10m FT8 long path by Darren, G0TSM. Darren also worked P29RO, the German DXpedition to Papua New Guinea, on all bands from 18 to 28MHz.

Next week NOAA predicts that the solar flux index will remain in the 100-118 range. Unfortunately, the Kp index is expected to rise to five on Saturday 29 October due to an enhanced solar wind stream from a trio of coronal holes on the Sun’s equator. This may no doubt impact conditions for the CQ Worldwide Phone Contest this weekend.

NOAA thinks the unsettled conditions could linger until Thursday 3 November when the Kp index may return to two.

And finally, please note that the data feed from the Chilton Digisonde has not been reliable this week. To circumvent this, on Propquest.co.uk/ we recommend selecting FF051 Fairford to maintain the graphs.

VHF and up

The autumnal weather remains in control and the basic pattern changes very little over the coming week.

This places low pressure to the southwest of the British Isles and a mild south-westerly wind bringing periods of rain as fronts cross the country with intervening spells of showery weather in between.

The result of all this for VHF and UHF propagation is that rain scatter continues to have a look-in on the GHz bands.  But this is very little comfort for tropo operators since high pressure does not really feature at all in the coming week, other than occasional weak transient events alongside weather fronts.

The ever-present chances of aurora are always a possibility, so keep up to date with VHF cluster reports of current activity levels to ensure you don’t miss out on any openings.

The Propquest.co.uk graphs have shown isolated occasions with Sporadic-E recorded on the foEs plots, so always worth a check on 10m and 6m for strong short skip European signals, especially on digital modes.

Random meteor scatter in the hours around dawn is always a banker for propagation and we are still in the tail end of the Orionid and Leonis Minoris showers to add to the mix. Next Sunday, the 6 November, marks the onset of the big Leonids shower, peaking around 16 November.

With the Moon at minimum declination this weekend, Moon windows will be short but lengthening as the week progresses. Perigee was yesterday, Saturday, so path losses are at their lowest. 144MHz sky noise is low in the coming week.

Category: GB2RS Propagation News