Propagation was a mixed bag last week with occasional Kp index rises but a solid solar flux index which hit 141 on Thursday 12 June. We also had some Sporadic-E short-skip conditions on the HF bands which brought some surprises. We are now in June so the summer HF doldrums are well under way. But […]

Last week’s HF propagation was heavily influenced by unsettled geomagnetic conditions. This was caused by a combination of coronal mass ejections and a strong solar wind from a coronal hole. The coronal mass ejection, or CME for short, followed a solar flare from sunspot 4100 on the 31 May at 0005UTC. The explosion lasted more […]

Last week’s high-speed solar wind, from a massive coronal hole on the Sun, took its toll on the HF bands. However, this week has been little better. Another coronal hole running diagonally across the Sun has been emitting particles that have pushed the Kp index up to a maximum of 6.67 which puts us into […]

A high-speed solar wind, originating from a massive coronal hole, took its toll on HF this past week. During the weekend of the 17th and 18th, the Kp index was above four for nine of the three-hourly recording periods. Unfortunately, the feed from the Dourbes Digisonde failed over this period, so we can’t comment on […]