Propagation News – 2 June 2024
Last week was characterised by relatively-quiet geomagnetic conditions and a fairly-high solar flux. But is that all about to change?
Active region 3664 has returned. It is now named 3697 and has already emitted an X1.4-class solar flare. You may recall that it was AR 3664 that caused the aurora that was visible all over the UK around the 10 and 11 May.
As Solarham.com says, “The chances for an Earth-directed eruption will increase with each passing day as the active sunspot region turns into a better geoeffective position.”
Scientists now believe that the coronal mass ejection associated with the long-duration X1.4-class flare on Wednesday 29 May could pass close enough to Earth to generate moderate G2 geomagnetic storming beginning on the 31 May – just in time for this weekend’s National Field Day!
Otherwise, HF propagation has generally been good with decent F2-layer openings up to 21 and even 24MHz at times.
The 17 and 15m bands look to provide the best DX, with paths to the east in the morning, and to the west during late afternoon and early evening.
The 10m band is subject to Sporadic-E openings, with F2-layer openings mainly restricted to paths to South Africa and South America.
Next week, NOAA predicts that the solar flux index will be in the 165 to 200 range, with quiet geomagnetic conditions. However, that is perhaps a little optimistic as active region 3697, or perhaps 3691, could easily throw a spanner in the works, with a flare and associated CME potentially sending the Kp index skywards.
So, as always, keep an eye on the current state of the Sun at solarham.com, and work the bands while they are open!
VHF and up
The close of the current week offers a temporary return of high pressure for this weekend. This should be good for some Tropo conditions for western parts of the UK. The weather turns a bit more unsettled going through the coming week, especially over northern Britain, but also occasionally in the south.
Rain at this time of the year can often be heavy and thundery with good prospects for GHz bands rain scatter, but this may have to wait for the end of next week when a low moves north from France towards the southern UK.
The early part of June is a time of several minor meteor showers. These should offer scope for meteor scatter operators as well as provide some fuel for Sporadic-E propagation which rocket measurements show consists of long-lived meteor ions.
Sporadic-E propagation is often associated with the position of jet streams in the upper troposphere due to the turbulence that these fast-flowing currents of air generate.
In the coming week, the jet stream pattern becomes much weaker, although still with a few options. Daily blogs are available at Propquest.co.uk for those who are interested.
Don’t ignore the prospects for multi-hop transatlantic paths to the United States and particularly the Caribbean, which are usually well supported in the early part of the season before the upper winds over the Caribbean change over to high-summer slacker flow.
Equally, multi-hop Sporadic-E paths to the Far East are worth checking in the early morning following the effects of the now displaced northerly meandering jet stream flow across northern Russia.
Moon declination went positive again on Saturday 1 June, so the coming week will see lengthening Moon windows. EME path loss is falling, reaching a minimum at perigee today, Sunday 2 June. 144MHz sky noise is low apart from Thursday when the Sun and Moon are close in the sky.
Category: GB2RS Propagation News
