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National Oceanic and Atmospheric Administration

Thursday, April 10, 2025 16:18:06 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.
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G3 Watch for 6 and 7 September, 2017 due to CME Arrival

G3 Watch for 6-7 Sep CME Arrival
G3 Watch for 6 and 7 September, 2017 due to CME Arrival
published: Thursday, September 07, 2017 00:26 UTC

The geomagnetic storm watch for the 6 and 7 September, 2017 UTC-days has been upgraded to G3 (Strong). The G3 Watch is in anticipation of the expected arrival of a coronal mass ejection (CME) that took place in association with an M5 flare (R2-Moderate radio blackout) observed on 4 September at 2033 UTC (1633 ET). Current analysis and forecasts reflect CME arrival late on 6 September, 2017; with CME effects continuing into 7 September. Keep checking our SWPC website for updates to the forecast.