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G2 (Moderate) Geomagnetic Storm Watch Issued for October 25

10/24/2017

The NOAA Space Weather Prediction Center (SWPC) said a G1 (minor) geomagnetic storm watch has been issued for October 24, and a G2 (moderate) geomagnetic storm watch has been issued for October 25.

In a G1 storm, weak power-grid fluctuations can occur, minor impact on satellite operations is possible, migratory animals may be affected, and aurora borealis is commonly visible at higher latitudes — e.g., northern Michigan and Maine. I

n a G2 storm, HF radio propagation can fade at higher latitudes, aurora may be seen as far south as New York and Idaho (typically 55°), high-latitude power systems may experience voltage alarms, and long-duration storms may cause transformer damage. Corrective actions to spacecraft orientation may be required by ground controllers, and possible changes in drag can affect orbit predictions.

A minor (R1) radio blackout was observed last Friday, October 20, at 2328 UTC. An R1 radio blackout can cause weak or minor degradation of HF radio communication on Earth’s sunlit side and occasional loss of radio contact. Low-frequency navigation signals may be degraded for brief intervals.



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