Propagation News – 21 June 2026
We had a quiet week geomagnetically, but the solar flux has also declined.
Over the past week, the Kp index never rose above 2 or 3, with only one three-hour excursion to 5 on Thursday 11 June. This bodes well for HF propagation, but the solar flux index has declined from its recent high of 148 on Thursday 4 June to be in the 110 to 120 range over the past week.
As a result, the Sun is looking a little sparse when it comes to sunspots. This, coupled with the summer doldrums, has seen maximum useable frequencies, or MUFs, drop and DX has been limited to 21MHz and below. The 10m band has been mainly open to Sporadic-E, with some multi-hop openings giving the appearance of F2-region propagation at times.
DX to be worked over the coming week includes: D44EC from Cape Verde; PJ2/PH2M from Curacao; 3G0YM on Easter Island; FS/K9EL operating from St Martin; 5R8EC from Madagascar; and OX3LX working from Greenland.
Next week, NOAA predicts that the solar flux index may increase slightly to be in the 130 to 140 range, although this will need some new additional sunspots. Geomagnetic conditions are forecast to be quiet with a maximum Kp index of 2. We may see a slight upturn on Tuesday 23 June, when the Kp index is predicted to rise to 4, mainly due to an enhanced solar wind.
To recap, Summer is a time when paradoxically daytime maximum useable frequencies, or MUFs, tend to be lower than in autumn and winter. However, nighttime MUFs can be higher, with the potential for the 30 and 20m bands to be open all night. ARRL Field Day will run from 1800UTC on Saturday 27 June to 2100UTC on Sunday 28 June. This may be an opportunity to work some US portable stations who will be very pleased to contact you.
VHF and up
The weather models are a bit undecided about how the coming week will evolve. One option is for predominantly high pressure and a chance of some summer tropo, which may persist over the sea, but is limited inland by daytime heating.
Tropo operators should focus on nighttime conditions, unless located right on the coasts. The other weather model suggests that low pressure will probably win out over northern areas and occasionally in the south, so rain scatter may be likely and it would need some heavy thundery showers to get the best results.
High summer is not the best for aurora. The Kp index ideally needs to be at least above 5 before we can get excited.
Meteor scatter operators have been making use of the decaying Arietids from earlier in June. The second shower of interest this month is the June Bootids. The window of activity will be from tomorrow, the 22 June, to Thursday 2 July with the peak on Saturday 27 June.
The Sporadic-E season is progressing with most days offering something from the 10 and 6m bands within Europe. However, there are limited possibilities on the 2m band. As usual, digital modes will be the first to see results, so use the FT8 paths as a guide for the other modes which should follow as the Sporadic-E intensifies.
Multi-hop paths do happen regularly but require beams and a lot of luck for several Sporadic-E patches to align. This means the best policy will be listening at the right time. This is in the morning for the paths to the Far East and in the evening for those to the States and Caribbean.
EME now and Moon declination is decreasing again, going negative today, 21 June, with path losses rising now the Moon is past perigee. This means shortening Moon windows and lower peak Moon elevation as the week progresses. 144MHz sky temperature is low, rising to moderate by Friday 26 June.
Category: GB2RS Propagation News
