Geomagnetic storm forecast - 8^th December 2025

We are expecting an increase in geomagnetic activity tonight, the 8^th-9^th of December, due to an anticipated coronal mass ejection (CME) arrival.

An Earth-directed CME left the Sun at approximately 20:39 UT on the 6^th of December. It was associated with an M-class solar flare originating from an active region AR14299, close to the centre of the solar disc.

The CME is expected to arrive either late on the 8^th or early on the 9^th of December likely to lead to a significant enhancement in geomagnetic activity, with chances of prolonged STORM periods.

Assuming clear dark skies, there is an increased chance of seeing the aurora tonight, the 8^th-9^th of December. Those in Scotland, northern England and Northern Ireland have the best chance if the weather is favourable.

Sign-up to receive Geomagnetic Storm Forecast emails.

Follow us on Twitter:

Follow @BGSauroraAlert for more occasional aurora alerts.

Follow @BGSspaceWeather for daily space weather forecasts.

Glossary

BGS

The British Geological Survey is a geoscience research centre that is part of UK Research and Innovation (UKRI) and affiliated to the Natural Environment Research Council (NERC).

CME or Coronal Mass Ejection

The eruption of a portion of the outer atmosphere of the Sun into space, caused by rapid changes in its magnetic field. Often occurs along with a solar flare.

Solar Flare

Energy released by the explosive reorganisation of magnetic fields within the Sun's atmosphere.

Sunspot/Active Region

A region of intense magnetic field in the Sun's visible outer atmosphere often associated with flares and CMEs.