Propagation News – 06 August 2023

The Sun continued to be very active over the last week with a large number of sunspots, numerous C- and M-class flares, and a coronal mass ejection or two.

A coronal mass ejection is predicted to hit Earth this weekend, which could see the Kp index rise, but this is not expected to be too extensive.

Active region 3380 expanded in both size and magnetic complexity, firing off numerous solar flares. Luckily it is now rotating out of view so is no longer a threat.

The Solar Flux Index remained above 170 all week with a sunspot number of 135 on Thursday. Don’t forget that this doesn’t mean there were 135 sunspots, as each group counts ten towards the total. Three sunspots in three groups equals thirty plus three, or thirty-three.

Geomagnetic conditions were mixed with one period giving a Kp index of four, and many when it was over three.

The main DX being chased this week wasn’t actually too far away. The 1A0C station at the Sovereign Military Order of Malta, which confusingly is actually in Rome, gave amateurs plenty of opportunity to add to their band slot totals. The station was raising money for humanitarian charitable projects and was easy to work from the UK.

Next week NOAA’s Space Weather Prediction Centre thinks the Solar Flux Index will remain in the 165 to 170 region. The Kp index shouldn’t rise above three, although that rather depends on whether we have any coronal mass ejections.

There are also signs that we are starting to leave the Summer HF doldrums. MUFs over a 3,000km path have occasionally gone over 28MHz at times. But we are still a long way from Autumn HF conditions, despite the weather!

VHF and up

The unsettled weather is here for a little longer, but there may be an end in sight as we move through the second half of next week.

To begin, there will be areas of low pressure in control bringing rain or showers and more rain scatter on the GHz bands.

Midweek, the high edges in from the west and remains close to the southeast into the next weekend, but lows and weather fronts will probably return to the western areas by the end of the week. Nonetheless, this should be a period of Tropo for many areas, if only temporarily for western areas.

Meteor scatter could be good with a steady advance towards the peak of the Perseids on the 12 and 13 August. It might even be warm enough to stand outside in the southeast and listen to the pings while watching the evening sky for meteor trails!

Aurora can’t be discounted either should the Kp index show higher values than, say, 5 and there have been a number of auroral contacts reported by Nordic stations over the last week.

In August there is still some Sporadic-E to be had as luckily the jet stream pattern is still quite busy giving ample triggers for Sporadic-E due to the turbulence they create. As often mentioned, a good time to check, if you are a busy person, is around teatime or late afternoon.

Moon declination goes positive on Saturday so Moon visibility windows will lengthen throughout the week. We are past perigee so path losses are rising again. 144MHz sky noise is low but rising, reaching moderate levels next weekend.

Category: GB2RS Propagation News