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HF News
Last week went pretty much as predicted. The solar wind from a large coronal hole impacted the Earth on Saturday, February the 1st, pushing the Kp index to four. The hole was so large that the geomagnetic disturbance lasted through until early evening on Sunday.
Once the solar wind speed had dropped things got back to normal and the Kp index has been in the range of one to two ever since.
The event appeared to have little effect on HF propagation, with MUFs over 3000km remaining above 28MHz during the daylight hours, so it looks like we dodged a bullet.
At the time of writing, we have had 21 M-class flares in three days.
A solar flare measuring M8.8 was detected around active region 3981, peaking at 03:58hrs UTC on February 3. This was the strongest flare yet from this region in terms of peak X-Ray flux. However, the flare itself was impulsive and was not the source of a coronal mass ejection.
Over the next week, NOAA predicts that the solar flux index could fall slightly to be in the range 180-200. Make the most of the good conditions as we may be entering a period of unsettled geomagnetic conditions again from February 10 to 17. NOAA predicts that the Kp index could rise to a maximum of five on the 13th, but is likely to be in the range of three to five over the seven-day period.
Part of this may be down to another coronal hole, which will become Earth-facing on February 6. There is also a good chance that we could get an X-class eruptive flare from active region 3981 or 3978, which could result in a CME.
We recommend you keep an eye on solarham.com for daily updates.
VHF and up
High pressure during the second half of last week brought some useful Tropo conditions. As this last week closed, there were some wintry showers along North Sea coasts, which possibly produced some snow/rain scatter but this was probably weakened by the nearby high pressure.
By the end of this first weekend, there will be a change of weather pattern as the high, having now migrated to Scandinavia, leaves room for Atlantic weather systems to encroach from the west during the coming week. This could bring the western side of the country into rain scatter possibilities and these should be more useful than the eastern coast ones at the end of last week since the rain will probably be heavier and the fronts slow-moving.
This time of year is something of a desert for Sporadic-E although look out for lesser events as a result of jet streams, which you can track on the Propquest website.
Keep a look out for auroras the week beginning the 10th. The likelihood of M-class flares is around 85 per cent, while the chance of X-class flares is approximately 20 per cent, so keep an eye on the Kp index for any potential solar events that could cause auroras.
During the upcoming week, there are no major meteor showers. The next significant meteor shower, the Lyrids, will become active in April. Keep checking the pre-dawn period for random meteors.
Moon declination reaches a maximum on Saturday the 8th. Path losses are still low, but increase throughout the coming week. This means that this first weekend, the 8th and 9th, should produce good activity for EME, especially on the GHz bands with long Moon windows and high peak Moon elevation.
144MHz sky noise starts this first weekend moderate, but falls to low, for the rest of the week.