725
WOXX15 KWNP 162056
ALTK08

Space Weather Message Code: ALTK08
Serial Number: 50
Issue Time: 2025 Apr 16 2054 UTC

ALERT: Geomagnetic K-index of 8, 9-
Synoptic Period: 1800-2100 UTC
Active Warning: Yes
NOAA Scale: G4 - Severe
www.swpc.noaa.gov/noaa-scales-explanation
Potential Impacts: Area of impact primarily poleward of 45 degrees Geomagnetic Latitude.
Induced Currents - Possible widespread voltage control problems and some protective systems may mistakenly trip out key assets from the power grid. Induced pipeline currents intensify.
Spacecraft - Systems may experience surface charging; increased drag on low earth orbit satellites, and tracking and orientation problems may occur.
Navigation - Satellite navigation (GPS) degraded or inoperable for hours.
Radio - HF (high frequency) radio propagation sporadic or blacked out.
Aurora - Aurora may be seen as low as Alabama and northern California.

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