Compiled by G0KYA, G3YLA and G4BAO on 23 April, 2026 Last week’s HF propagation was dominated by the effects of a high-speed stream from a large coronal hole on the Sun. This pushed the Kp index up to 4 and 5 at times with the result that maximum usable frequencies, or MUFs, were lowered. The […]

Compiled by G0KYA, G3YLA and G4BAO on 16 April, 2026 Last week was characterised by a low Kp index and an equally low solar flux index. The Kp index was predominately below 2 all week thanks to a lack of Earth-directed CMEs, or coronal holes. Unfortunately, that is about to change. The solar index has […]

Compiled by G0KYA, G3YLA and G4BAO on 9 April, 2026. After a pretty stormy run-up to Easter, from a geomagnetic disturbance point of view, the Sun has been quieter. In fact, the Kp index has been below 3 all week. Unfortunately, the solar flux index has also declined, standing at 108 on Thursday, 9 April. The […]

Over the last week we have had a fair sprinkling of sunspots, along with some enormous coronal holes, including one almost rectangular hole. Coronal holes are lower energy areas on the Sun with open magnetic field lines, allowing solar plasma to flow out. Geomagnetic conditions have mainly been settled, with the Kp index hitting a […]