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National Oceanic and Atmospheric Administration

Tuesday, July 29, 2025 22:01:25 UTC

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NOAA Scales mini

R1 (Minor) Radio Blackout Impacts
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HF Radio: Weak or minor degradation of HF radio communication on sunlit side, occasional loss of radio contact.
Navigation: Low-frequency navigation signals degraded for brief intervals.
More about the NOAA Space Weather Scales

G1 geomagnetic storm conditions

SDO/AIA composite image
G1 geomagnetic storm conditions
published: Saturday, December 12, 2015 12:41 UTC

A positive polarity coronal hole high speed stream, reaching upwards of 600 km/s, arrived at Earth as forecast. The increased wind speeds combined with a disturbed solar wind environment were enough to enhance the geomagnetic field to G1-Minor storm conditions. G-1 conditions are expected to occur periodically though out the day today as well as into tomorrow (11 Dec). 

Stay tuned here for updates.