# Solar activity and geomagnetic storm events

> Live situation record from CLSTR: https://clstr.news/situations/solar-activity-and-geomagnetic-storm-events
> Updated: 2026-08-25T14:50:50.000Z. Sources: 6. Developments: 2.

Solar activity in late August 2026 has triggered various space weather warnings. An M6.9 solar flare from Active Region 4513 caused a moderate (R2) radio blackout affecting high-frequency communications in the Arctic, Europe, and parts of Africa.

Following the detection of Earth-directed coronal mass ejections (CMEs) associated with the M6.9 flare and a subsequent C4.7 flare, NOAA’s Space Weather Prediction Center issued a G2 moderate geomagnetic storm watch for August 28. Additionally, a G1 minor geomagnetic storm watch was issued for August 27 due to an approaching coronal-hole high-speed stream.

While earlier forecasts suggested a 55% probability of moderate radio interference and a 15% risk of stronger events, the specific flare activity has confirmed immediate impacts on radio communications. Potential broader effects include minor power grid fluctuations and satellite system issues.

## Timeline

### 2026-08-25: Solar flare and CME trigger geomagnetic storm watches

A powerful M6.9 solar flare and Earth-directed coronal mass ejections have prompted geomagnetic storm watches for August 27 and 28, potentially affecting radio communications and aurora visibility.

4 sources. https://clstr.news/cluster/solar-flare-and-cme-trigger-geomagnetic-storm-watches

### 2026-08-25: NOAA forecasts solar activity and radio interference for late August 2026

NOAA forecasts suggest a 55% chance of moderate radio interference (R1–R2) on August 28, 2026, despite no immediate prediction of a G1-level geomagnetic storm.

2 sources. https://clstr.news/cluster/noaa-forecasts-solar-activity-and-radio-interference-for-late-august-2026

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Cite as: Solar activity and geomagnetic storm events. CLSTR, https://clstr.news/situations/solar-activity-and-geomagnetic-storm-events