Propagation News – 24 May 2026

Compiled by G0KYA, G3YLA and G4BAO on 21 May.

Last weekend’s geomagnetic disturbance didn’t turn out to be quite as bad as predicted.

A high-speed solar wind stream from a massive coronal hole and a coronal mass ejection caused the Kp index to rise to 6.33 on Friday, 15 May but it subsided and we were soon back to more normal figures in the range of 2 to 4.

The last week has seen more usual Kp figures in the range of 2 to 3 which bodes well for HF propagation.

Unfortunately, the solar flux index has been stuck in the low one hundreds, ranging from 109 on 16 May to 106 on 20 May. It rose to 114 on 21 May, which may continue into the coming week.

Meanwhile, ESA’s Solar Orbiter has been monitoring solar activity on the far side of the Sun, which continues to feature a number of large sunspot groups.

A number of C-class Flares and one low-level M-flare have been detected on the far side.

We will have to wait until next week for that activity to rotate to an Earth-facing position.

Much of the activity on the higher HF bands is currently due to Sporadic-E and Jim, G3YLA reports several multi-hop paths showing up between Europe to the Caribbean and the USA on the 6m band.

A quick check on the 10m band revealed only low power beacons out of Spain and Andorra, unfortunately.

NOAA predicts that the solar flux index may rise to 115 tomorrow, 25 May, and then increase to 135 by the end of the month.

The start of the coming week should see settled geomagnetic conditions but we are predicted to see a rise in the Kp index to 4 on Wednesday, 27 May.

VHF and up propagation news

by G3YLA and G4BAO

The recent lengthy period of indifferent weather has now changed over to a predominantly high-pressure type. This should last through to the end of the coming week when a possible return to unsettled weather edges up from the south.

Starting with the large-scale pressure pattern, it will be a period of improving tropo conditions for the VHF and UHF bands as the high builds over the country.

The conditions should cover a large area across the North Sea and into the near continent.

It is often the case that lift conditions may be improved by nighttime cooling and fade slightly during the day, unless over a sea path, which doesn’t change much from day to night.

The late May and early June period is a reasonable time for meteor activity, although this is mostly minor. Remember that there is still the tail end of the Eta Aquarids to work through this month.

The solar conditions have offered up some reasonable coronal holes recently and, although the light evenings don’t allow visual confirmation, the Kp index going above 7 should make life more interesting for aurora.

Needless to say, rain scatter will not feature in a predominantly high-pressure period of weather.

Lastly, a thought about sporadic-E which is coming into full bloom now and is typically at a peak around early to mid-June.

There have been some successful openings on the 6m band with some multi-hop paths to the Far East and across to the States and Caribbean.

On the basis that jet streams may be useful indicators of where Sporadic-E is more likely, the coming week will see the main jet stream flow being pushed well north to a typical summer position from Iceland to Scandinavia.

This might make paths to Scandinavia and the Baltic a good option, including northern multi-hop paths to the Far East.

EME now and Moon declination is falling again, going negative tomorrow, 25 May.

Combined with increasing path losses, conditions will worsen as the week progresses but there is still plenty of time to make some QSOs, albeit with shorter Moon windows and lower peak elevation.

144MHz sky temperature is low but increasing to moderate by Friday, 29 May.

Category: GB2RS Propagation News