RSGB
RadCom Assistant Editor | August 21, 2026
Compiled by G0KYA, G3YLA and G4BAO on 20 August, 2026
Last week was characterised by geomagnetic disturbances, due to high-speed solar wind streams from coronal holes and a slightly increasing solar flux index.
The Kp index hit 5 on 18-19 August, reducing maximum useable frequencies, or MUFs, and generally being detrimental to HF propagation.
We also had more than 50 C-class solar flares and one M-class event this past week, so nothing too severe. It was coronal holes that did the damage with two large areas on the Sun. A coronal hole is an area of the Sun with open magnetic field lines that allows solar plasma to escape.
HF conditions were relatively poor during International Lighthouse and Lightship Weekend on Sunday, 16 August, with little DX and heavy QSB or fading. The MUF struggled to get to 21MHz, and most activity was on the 40 and 20m bands.
Some transatlantic signals were logged but they were weak and watery. That didn’t stop people from enjoying the event, though!
DX to be worked this week includes 3B8/SQ9UM from Mauritius; RI8KR from Asiatic Russia; RI1FJL operating from Franz Josef Land; V47JA on St Kitts; and V51WH and V55Y active in Namibia.
Good news this week as Propquest is back online, showing near real-time MUFs over various distances. Jim, G3YLA says this is a temporary fix pending further work.
NOAA predicts that we will see a solar flux index around 100 to 120 next week, with relatively poor geomagnetic conditions forecast for today, 23 August. The Kp index is predicted to be around 2 during the coming week.
At the time of writing, there are no coronal holes threatening HF propagation but keep an eye on solarham.com for updates.
We are still analysing the eclipse experiment data, but a video of the 80m WSPR contacts has been produced and can be found at tinyurl.com/80mWSPR
VHF and up propagation news:
Compiled by G3YLA and G4BAO
The return of unsettled weather last week pauses over this weekend, ending today, 23 August as a new high moves across the country from the Atlantic.
This gives a good chance for some tropo and, if the land temperatures pick up again and drift offshore, it could produce some good conditions across sea paths like the North and Irish Seas.
Before midweek, probably during Tuesday, low pressure will return and push a frontal system across the country followed by further fronts and showery periods for the rest of the week.
This could be very good for rain scatter on the GHz bands, especially if the showers turn thundery.
Meteor scatter will be largely random activity for most of the coming week. We will also see the end of the Delta Aquarids today, 23 August and the final trailing off from the Perseids, which end tomorrow, 24 August.
The solar conditions are worth monitoring after recent activity saw the Kp index reach 5 on Tuesday and Wednesday last week. Ideally, we require something a little higher to start considering auroral propagation from the southern UK.
Sporadic-E can last into the first week of September but tends to become harder to find and shorter in duration. There is no reason to stop checking, though – anytime from mid-morning to late afternoon should cover it.
For EME operators, the Moon was at apogee and at minimum declination yesterday, 22 August. With minimum peak elevation and maximum path losses, it’s a good excuse to check out the mechanics of your antenna.
144MHz sky noise is very high today, 23 August, falling back to low as the week progresses.
(Mike Terry, UK/BDXC)
