Space weather forecast predicts potential minor geomagnetic storm for September 15, 2026

Space weather forecasts for September 15, 2026, indicate a period of moderate geomagnetic activity. Data from the NOAA Space Weather Prediction Center suggests a potential for a brief G1-class minor geomagnetic storm. This possibility is driven by an expected high-speed stream from a coronal hole that may position itself favorably toward Earth, increasing solar wind activity.

The predicted Kp index for the period is expected to reach a peak of 3.67 between 03:00 and 06:00 UTC. While the overall forecast remains relatively calm, NOAA estimates a 30% probability of a minor G1 geomagnetic storm on this date. The likelihood of more intense events, such as moderate storms or significant solar radiation storms, remains very low at 5% and 1% respectively.

Regarding radio activity, there is a 10% chance of R1 to R2 class radio blackouts, while the probability of stronger R3 class events is only 1%. Such solar activity can result in phenomena such as auroras, satellite interference, and potential disruptions to power grids or radio communications.