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National Oceanic and Atmospheric Administration

Sunday, April 06, 2025 18:25:30 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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M9 Flare (R2-Moderate) Event on 16 May, 2023

R2 Event on 16 May, 2023
M9 Flare (R2-Moderate) Event on 16 May, 2023
published: Thursday, May 18, 2023 16:19 UTC

A M9.6 flare (R2-Moderate HF Radio Blackout) occurred on 16 May at 12:43 pm EDT (1643 UTC). The flare erupted from a yet to be observed active region just beyond the southeast limb of the visible solar disk. However, the NSO - Gong (National Solar Observatory - Global Oscillation Network Group) helioseismology observation detected a noteworthy signature just about to rotate into Earth-view in another day or so. SWPC forecasters utilize this technology when available to assist in forecast decision-making. Continue to monitor our SWPC website for the latest information and forecasts.