Space Weather Presentation: SWPC warns geomagnetic storms can disrupt power, GPS and communications

At the Dane County Local Emergency Planning Committee meeting on June 9, a Space Weather Prediction Center (SWPC) service coordinator briefed committee members on how solar activity can affect power systems, satellite operations, GPS precision, aviation communications and emergency radio systems.

Sean (last name not specified), service coordinator and senior space weather forecaster at the SWPC, National Weather Service, told the committee that space weather originates on the sun and can reach Earth in minutes (for electromagnetic radiation) to hours or days (for particles and coronal mass ejections). He said SWPC’s mission is “safeguarding society with actionable space weather information.”

Sean emphasized three phenomena emergency managers should understand: solar radiation storms (S scale), high‑frequency (HF) radio blackouts caused by solar flares (R scale) and geomagnetic storms driven by coronal mass ejections (G scale). He explained that solar flares can immediately degrade HF radio on the sunlit side of Earth, sometimes within minutes; energetic radio bursts can temporarily jam VHF/UHF air‑traffic communications; and coronal mass ejections (CMEs) can drive geomagnetic storms that induce currents on long high‑voltage transmission lines.

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