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Monday, August 18, 2025 17:07:56 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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R2-Moderate Radio Blackout Observed 17 April 8:29 pm EDT

R2 Radio Blackout and 30MhZ D-Region Absorption Graphic
R2-Moderate Radio Blackout Observed 17 April 8:29 pm EDT
published: Wednesday, April 20, 2016 19:03 UTC

R2 (Moderate) radio blackouts were observed at 18/0029 UTC (April 17, 2016 at 8:29 pm EDT) due to an impulsive M6 flare from NOAA Region 2529. A coronal mass ejection occurred in relation to this event, however forecaster analysis suggests an Earth-directed component is unlikely.