British Geological Survey.
We are expecting an increase in geomagnetic activity on Friday and throughout the weekend due to the combined effects of a coronal hole high speed stream (HSS) and the arrival of an Earth-directed Coronal
Mass Ejection (CME).
An M4.5-class solar flare occurred in the centre of the solar disk on 5th August 2025 at 15:53 UT.
This flare produced a CME that is traveling toward Earth at a moderate speed of over 500 km/s.
Additionally, the high speed stream from a recurrent coronal hole (CH69) is due to arrive on Friday.
The combined effect of the CME and the HSS is expected to enhance geomagnetic activity on Friday 8th August 2025 up to minor geomagnetic
storm level or G3 on the NOAA scale.
https://geomag.bgs.ac.uk/data_service/space_weather/alerts/alert_2025-08-06.html
Mike Terry to WOR iog (2025-08-06)