Warning!

Javascript is disabled on this browser.
Javascript must be enabled for this website to display and function correctly.

BGS Global Geomagnetic Activity Forecast

Forecast period
(noon-to-noon GMT) 		Forecast Global Activity level
Average Max
18 MAY-19 MAY QUIET STORM G1
19 MAY-20 MAY QUIET STORM G2
20 MAY-21 MAY QUIET STORM G1

For more information about the forecast and activity categories see
geomag.bgs.ac.uk/education/activitylevels.html

Activity during last 72 hours

Global   Local (UK)
Date Average Max At time (UTC) Average Max At time (UTC)
15 MAY-16 MAY STORM G1 STORM G2 21:00-00:00 STORM G1 STORM G2 21:00-00:00
16 MAY-17 MAY QUIET STORM G1 15:00-18:00 ACTIVE STORM G1 15:00-18:00
17 MAY-18 MAY QUIET QUIET 12:00-15:00 QUIET QUIET 03:00-06:00
QUIET 03:00-06:00

Additional Comments

The influence of a coronal hole high speed stream (HSS) led to elevated geomagnetic activity over the weekend, reaching STORM G2 levels. The effects are now waning, with solar wind speed decreasing, but some further ACTIVE periods may be possible before it reaches background levels.
On 15th and 16th May there were three coronal mass ejections (CMEs) that left the Sun. All three were mostly directed northwards, so the bulk of the ejecta is likely to miss the Earth, but there may be a chance for glancing blows. The first CME is likely to miss the Earth, but may have a slight chance for a glancing impact during the first forecast interval. The second two CMEs have a chance of a glancing impact during the second and third forecast intervals, which could lead to periods of up to STORM G2 geomagnetic conditions.
Time of forecast: 18 May 2026
© UKRI