Propagation News – 28 June 2026

Things have been quiet on the solar front but that may be about to change.

The solar flux index has been sitting around the low 120s for a few days and the geomagnetic Kp index has been below 2.

Other than a couple of M-class solar flares, activity has been rather quiet. One of the flares was the source of a faint, easterly-directed coronal mass ejection, or CME, with no Earth-directed component.

But there are a number of solar features that could change all that. Firstly, a coronal hole on the Sun’s surface became geoeffective on Wednesday 24 June meaning a solar wind stream could impact the Earth.

Expect the Kp index to rise, perhaps to 4 as a result, and maximum useable frequencies to drop. Hopefully today, 28 June, this will clear.

Meanwhile, a large sunspot group is due to appear from around the Sun’s eastern limb. The cluster as observed by the ESA solar orbiter spacecraft shows arch-like structures known as coronal loops seen towering over the east limb.

Quite what this will do for HF propagation is hard to say so keep an eye on solarham.com for updates.

DX to be worked next week includes FP/KV1J from St Pierre and Miquelon; JD1BQP from Ogasawara; 5H3DX in Tanzania; CN2NQV from Morocco; FO/F6BCW in French Polynesia; and PJ2/PH2M operating from Curacao.

HF conditions have been relatively poor with many stations complaining that there is not much activity. A quick check revealed little action on 21MHz and higher, other than Sporadic-E openings. So, it looks like 14 and 18MHz are the main DX bands at the moment.

NOAA predicts that the solar flux index may increase to 145 by Wednesday 1 July. Once we get over the effects of the coronal hole’s high-speed solar wind stream the Kp index is predicted to go back down to 2.

VHF and up

The typical high summer patterns of jet streams take a step back in mid-summer. However, any that do crop up can give plenty of value for Sporadic-E since the ionosphere is well primed by meteor debris from the June Bootids.

Multi-hop Sporadic-E paths to the US and Far East are likely to be a surprise at times, often short-lasting for individual stations, but overall it is a good time of the season to be optimistic.

It can be a challenge at this time of year since tropo is also a strong player due to the hot air from the land moving out across the cooler sea water around the UK.

This provides ideal duct conditions that persist over the waters throughout the day but may struggle for stations well inland. It can also cause confusion as to whether you are working Sporadic-E or tropo on occasions. If it is tropo, it will be much longer lasting and particularly good overnight on the high bands. If the path works on the 70cm band it is probably tropo.

Meteor scatter is best around the random period maximum, which is just around dawn. Rain scatter is a good option. Watch for lightning activity as a clue for intense precipitation. If you are fed up with all that, the long-shot option might be aurora, but that is relatively rare in high summer and not visible easily.

EME now, and path losses are high as the Moon is near apogee, its furthest point from Earth. Declination is also at a minimum. Sky noise is currently high but will improve as the week goes on.

Category: GB2RS Propagation News