Propagation News – 14 June 2015

HF propagation during last weekend’s field day was pretty much as predicted. Conditions were settled, but there wasn’t an awful lot of DX to be had, with F2 layer openings topping out at 21MHz at times. This was mainly due to summer HF conditions with lower daytime MUFs.

The beginning of the week saw the very unsettled geomagnetic conditions we warned you about, with the Kp index hitting five due to the effects of a solar wind stream from a coronal hole. What no-one really predicted was the sharp increase in the solar flux index, due to some new sunspots.

Next week should see the solar flux index sitting around the 120 mark and reasonably settled geomagnetic conditions with a Kp index of about two. Nevertheless, the optimum working frequency on paths around 3,000km may remain at about 14MHz. Forty metres may also be poor during the day due to high levels of absorption and lower critical frequencies.

The only bright spot will be the continued seasonal Sporadic-E openings on 10m. But, as always in the summer, do check the HF bands after dark as you may find 20m remaining open all night and 15m offering openings to South America in the late evening.

The 5th of June saw 5.7 and 10GHz rain scatter propagation into the continent for those in the Southeast of England, with QSOs well into Germany.

The main weather feature this coming week will be a new area of high pressure to the West of Britain. Later in the week, the models suggest it will be more centrally placed over the UK. Initially, Tropo paths are more likely down the western side of Britain and across Biscay to the Azores, Canaries and western Spain, with a weaker Tropo event closer to home with possible paths into the near Continent from Monday.

The Sporadic-E season is now well under way, with almost daily openings on 50MHz and extensions up to 70 and 144. There was a widespread opening on 144MHz on the 9th of June that allowed a few UK stations to work as far as the Balkans, Italy and Portugal.

At this season peak, expect openings outside the traditional late morning and late afternoon periods and look on 6 and 4m in the late evening for northerly paths to OY, TF, OX and beyond.

Also don’t rule out Es occurring when the K index is higher than three. While not be so secure, there have been some quite acceptable Es openings recently with a K index of 4.

And that’s all from the propagation team for this week.

Category: GB2RS Propagation News