418 WOXX15 KWNP 110851 ALTK08 Space Weather Message Code: ALTK08 Serial Number: 48 Issue Time: 2024 Oct 11 0848 UTC ALERT: Geomagnetic K-index of 8, 9- Synoptic Period: 0600-0900 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. # Issued by the US Dept. of Commerce, NOAA, Space Weather Prediction Center # Recent messages, data, and help at http://swpc.noaa.gov/alerts/ # Send questions to SWPC.Webmaster@noaa.gov