Local 3/21/2026, 1:54:56 AM
UTC 2026-03-21T01:54:56.203Z
Space Weather Message Code: ALTK07Serial Number: 213Issue Time: 2026 Mar 21 0154 UTCALERT: Geomagnetic K-index of 7Threshold Reached: 2026 Mar 21 0154 UTCSynoptic Period: 0000-0300 UTCActive Warning: YesNOAA Scale: G3 - StrongNOAA Space Weather Scale descriptions can be found atwww.swpc.noaa.gov/noaa-scales-explanationPotential Impacts: Area of impact primarily poleward of 50 degrees Geomagnetic Latitude.Induced Currents - Power system voltage irregularities possible, false alarms may be triggered on some protection devices.Spacecraft - Systems may experience surface charging; increased drag on low Earth-orbit satellites and orientation problems may occur.Navigation - Intermittent satellite navigation (GPS) problems, including loss-of-lock and increased range error may occur.Radio - HF (high frequency) radio may be intermittent.Aurora - Aurora may be seen as low as Pennsylvania to Iowa to Oregon.
Local 3/21/2026, 1:41:52 AM
UTC 2026-03-21T01:41:52.367Z
Space Weather Message Code: ALTK06Serial Number: 702Issue Time: 2026 Mar 21 0141 UTCALERT: Geomagnetic K-index of 6Threshold Reached: 2026 Mar 21 0141 UTCSynoptic Period: 0000-0300 UTCActive Warning: YesNOAA Scale: G2 - ModerateNOAA Space Weather Scale descriptions can be found atwww.swpc.noaa.gov/noaa-scales-explanationPotential Impacts: Area of impact primarily poleward of 55 degrees Geomagnetic Latitude.Induced Currents - Power grid fluctuations can occur. High-latitude power systems may experience voltage alarms.Spacecraft - Satellite orientation irregularities may occur; increased drag on low Earth-orbit satellites is possible.Radio - HF (high frequency) radio propagation can fade at higher latitudes.Aurora - Aurora may be seen as low as New York to Wisconsin to Washington state.
Local 3/21/2026, 12:34:35 AM
UTC 2026-03-21T00:34:35.307Z
Space Weather Message Code: ALTK05Serial Number: 1981Issue Time: 2026 Mar 21 0034 UTCALERT: Geomagnetic K-index of 5Threshold Reached: 2026 Mar 21 0033 UTCSynoptic Period: 0000-0300 UTCActive Warning: YesNOAA Scale: G1 - MinorNOAA Space Weather Scale descriptions can be found atwww.swpc.noaa.gov/noaa-scales-explanationPotential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude.Induced Currents - Weak power grid fluctuations can occur.Spacecraft - Minor impact on satellite operations possible.Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.
Local 3/20/2026, 11:29:12 PM
UTC 2026-03-20T23:29:12.240Z
Space Weather Message Code: ALTK07Serial Number: 212Issue Time: 2026 Mar 20 2329 UTCALERT: Geomagnetic K-index of 7Threshold Reached: 2026 Mar 20 2328 UTCSynoptic Period: 2100-2400 UTCActive Warning: YesNOAA Scale: G3 - StrongNOAA Space Weather Scale descriptions can be found atwww.swpc.noaa.gov/noaa-scales-explanationPotential Impacts: Area of impact primarily poleward of 50 degrees Geomagnetic Latitude.Induced Currents - Power system voltage irregularities possible, false alarms may be triggered on some protection devices.Spacecraft - Systems may experience surface charging; increased drag on low Earth-orbit satellites and orientation problems may occur.Navigation - Intermittent satellite navigation (GPS) problems, including loss-of-lock and increased range error may occur.Radio - HF (high frequency) radio may be intermittent.Aurora - Aurora may be seen as low as Pennsylvania to Iowa to Oregon.
Local 3/20/2026, 11:05:56 PM
UTC 2026-03-20T23:05:56.793Z
Space Weather Message Code: WARK07Serial Number: 145Issue Time: 2026 Mar 20 2305 UTCWARNING: Geomagnetic K-index of 7 or greater expectedValid From: 2026 Mar 20 2305 UTCValid To: 2026 Mar 21 0600 UTCWarning Condition: OnsetNOAA Scale: G3 or greaterNOAA Space Weather Scale descriptions can be found atwww.swpc.noaa.gov/noaa-scales-explanationPotential Impacts: Area of impact primarily poleward of 50 degrees Geomagnetic Latitude.Induced Currents - Power system voltage irregularities possible, false alarms may be triggered on some protection devices.Spacecraft - Systems may experience surface charging; increased drag on low Earth-orbit satellites and orientation problems may occur.Navigation - Intermittent satellite navigation (GPS) problems, including loss-of-lock and increased range error may occur.Radio - HF (high frequency) radio may be intermittent.Aurora - Aurora may be seen as low as Pennsylvania to Iowa to Oregon.
Local 3/20/2026, 10:12:22 PM
UTC 2026-03-20T22:12:22.787Z
Space Weather Message Code: ALTK06Serial Number: 701Issue Time: 2026 Mar 20 2212 UTCALERT: Geomagnetic K-index of 6Threshold Reached: 2026 Mar 20 2208 UTCSynoptic Period: 2100-2400 UTCActive Warning: YesNOAA Scale: G2 - ModerateNOAA Space Weather Scale descriptions can be found atwww.swpc.noaa.gov/noaa-scales-explanationPotential Impacts: Area of impact primarily poleward of 55 degrees Geomagnetic Latitude.Induced Currents - Power grid fluctuations can occur. High-latitude power systems may experience voltage alarms.Spacecraft - Satellite orientation irregularities may occur; increased drag on low Earth-orbit satellites is possible.Radio - HF (high frequency) radio propagation can fade at higher latitudes.Aurora - Aurora may be seen as low as New York to Wisconsin to Washington state.
Local 3/20/2026, 9:36:31 PM
UTC 2026-03-20T21:36:31.443Z
Space Weather Message Code: ALTK05Serial Number: 1980Issue Time: 2026 Mar 20 2136 UTCALERT: Geomagnetic K-index of 5Threshold Reached: 2026 Mar 20 2126 UTCSynoptic Period: 2100-2400 UTCActive Warning: YesNOAA Scale: G1 - MinorNOAA Space Weather Scale descriptions can be found atwww.swpc.noaa.gov/noaa-scales-explanationPotential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude.Induced Currents - Weak power grid fluctuations can occur.Spacecraft - Minor impact on satellite operations possible.Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.
Local 3/20/2026, 9:09:53 PM
UTC 2026-03-20T21:09:53.620Z
Space Weather Message Code: SUMSUDSerial Number: 296Issue Time: 2026 Mar 20 2109 UTCSUMMARY: Geomagnetic Sudden ImpulseObserved: 2026 Mar 20 2053 UTCDeviation: 56 nTStation: BOUNOAA Space Weather Scale descriptions can be found atwww.swpc.noaa.gov/noaa-scales-explanation
Local 3/20/2026, 9:04:30 PM
UTC 2026-03-20T21:04:30.617Z
Space Weather Message Code: ALTK06Serial Number: 700Issue Time: 2026 Mar 20 2104 UTCALERT: Geomagnetic K-index of 6Threshold Reached: 2026 Mar 20 2059 UTCSynoptic Period: 1800-2100 UTCActive Warning: YesNOAA Scale: G2 - ModerateNOAA Space Weather Scale descriptions can be found atwww.swpc.noaa.gov/noaa-scales-explanationPotential Impacts: Area of impact primarily poleward of 55 degrees Geomagnetic Latitude.Induced Currents - Power grid fluctuations can occur. High-latitude power systems may experience voltage alarms.Spacecraft - Satellite orientation irregularities may occur; increased drag on low Earth-orbit satellites is possible.Radio - HF (high frequency) radio propagation can fade at higher latitudes.Aurora - Aurora may be seen as low as New York to Wisconsin to Washington state.
Local 3/20/2026, 8:43:58 PM
UTC 2026-03-20T20:43:58.600Z
Space Weather Message Code: WATA50Serial Number: 96Issue Time: 2026 Mar 20 2043 UTCWATCH: Geomagnetic Storm Category G3 PredictedHighest Storm Level Predicted by Day:Mar 20: G3 (Strong) Mar 21: G3 (Strong) Mar 22: G1 (Minor)THIS SUPERSEDES ANY/ALL PRIOR WATCHES IN EFFECTComment: G3 (Strong) geomagnetic storming is likely due to combined CME effects from events that left the Sun on 16 and 18 Mar.NOAA Space Weather Scale descriptions can be found atwww.swpc.noaa.gov/noaa-scales-explanationPotential Impacts: Area of impact primarily poleward of 50 degrees Geomagnetic Latitude.Induced Currents - Power system voltage irregularities possible, false alarms may be triggered on some protection devices.Spacecraft - Systems may experience surface charging; increased drag on low Earth-orbit satellites and orientation problems may occur.Navigation - Intermittent satellite navigation (GPS) problems, including loss-of-lock and increased range error may occur.Radio - HF (high frequency) radio may be intermittent.Aurora - Aurora may be seen as low as Pennsylvania to Iowa to Oregon.
Local 3/20/2026, 8:40:35 PM
UTC 2026-03-20T20:40:35.003Z
Space Weather Message Code: WARSUDSerial Number: 251Issue Time: 2026 Mar 20 2040 UTCWARNING: Geomagnetic Sudden Impulse expectedValid From: 2026 Mar 20 2050 UTCValid To: 2026 Mar 20 2120 UTCIP Shock Passage Observed: 2026 Mar 20 2118 UTCNOAA Space Weather Scale descriptions can be found atwww.swpc.noaa.gov/noaa-scales-explanation
Local 3/20/2026, 8:22:56 PM
UTC 2026-03-20T20:22:56.357Z
Space Weather Message Code: WARK06Serial Number: 645Issue Time: 2026 Mar 20 2022 UTCWARNING: Geomagnetic K-Index of 6 expectedValid From: 2026 Mar 20 2020 UTCValid To: 2026 Mar 21 0600 UTCWarning Condition: OnsetNOAA Scale: G2 - ModerateComment: G2 (Moderate) geomagnetic storm conditions are expected into the the early portions of 21 Mar (UTC) due to CME effects.NOAA Space Weather Scale descriptions can be found atwww.swpc.noaa.gov/noaa-scales-explanationPotential Impacts: Area of impact primarily poleward of 55 degrees Geomagnetic Latitude.Induced Currents - Power grid fluctuations can occur. High-latitude power systems may experience voltage alarms.Spacecraft - Satellite orientation irregularities may occur; increased drag on low Earth-orbit satellites is possible.Radio - HF (high frequency) radio propagation can fade at higher latitudes.Aurora - Aurora may be seen as low as New York to Wisconsin to Washington state.
Local 3/20/2026, 8:18:58 PM
UTC 2026-03-20T20:18:58.940Z
Space Weather Message Code: ALTK05Serial Number: 1979Issue Time: 2026 Mar 20 2018 UTCALERT: Geomagnetic K-index of 5Threshold Reached: 2026 Mar 20 2018 UTCSynoptic Period: 1800-2100 UTCActive Warning: YesNOAA Scale: G1 - MinorNOAA Space Weather Scale descriptions can be found atwww.swpc.noaa.gov/noaa-scales-explanationPotential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude.Induced Currents - Weak power grid fluctuations can occur.Spacecraft - Minor impact on satellite operations possible.Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.
Local 3/20/2026, 7:32:04 PM
UTC 2026-03-20T19:32:04.137Z
Space Weather Message Code: WARK05Serial Number: 2208Issue Time: 2026 Mar 20 1932 UTCWARNING: Geomagnetic K-index of 5 expectedValid From: 2026 Mar 20 1930 UTCValid To: 2026 Mar 21 0900 UTCWarning Condition: OnsetNOAA Scale: G1 - MinorNOAA Space Weather Scale descriptions can be found atwww.swpc.noaa.gov/noaa-scales-explanationPotential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude.Induced Currents - Weak power grid fluctuations can occur.Spacecraft - Minor impact on satellite operations possible.Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.
Local 3/20/2026, 2:55:19 PM
UTC 2026-03-20T14:55:19.443Z
Space Weather Message Code: ALTEF3Serial Number: 3652Issue Time: 2026 Mar 20 1455 UTCCONTINUED ALERT: Electron 2MeV Integral Flux exceeded 1000pfuContinuation of Serial Number: 3651Begin Time: 2026 Mar 15 1630 UTCYesterday Maximum 2MeV Flux: 4941 pfuPotential Impacts: Satellite systems may experience significant charging resulting in increased risk to satellite systems.
Local 3/20/2026, 12:39:56 PM
UTC 2026-03-20T12:39:56.870Z
Space Weather Message Code: WARK04Serial Number: 5290Issue Time: 2026 Mar 20 1239 UTCEXTENDED WARNING: Geomagnetic K-index of 4 expectedExtension to Serial Number: 5289Valid From: 2026 Mar 20 0719 UTCNow Valid Until: 2026 Mar 21 1200 UTCWarning Condition: PersistenceNOAA Space Weather Scale descriptions can be found atwww.swpc.noaa.gov/noaa-scales-explanationPotential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.Induced Currents - Weak power grid fluctuations can occur.Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.
Local 3/20/2026, 8:54:56 AM
UTC 2026-03-20T08:54:56.533Z
Space Weather Message Code: ALTK04Serial Number: 2645Issue Time: 2026 Mar 20 0854 UTCALERT: Geomagnetic K-index of 4Threshold Reached: 2026 Mar 20 0854 UTCSynoptic Period: 0600-0900 UTCActive Warning: YesNOAA Space Weather Scale descriptions can be found atwww.swpc.noaa.gov/noaa-scales-explanationPotential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.Induced Currents - Weak power grid fluctuations can occur.Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.
Local 3/20/2026, 7:18:46 AM
UTC 2026-03-20T07:18:46.533Z
Space Weather Message Code: WARK04Serial Number: 5289Issue Time: 2026 Mar 20 0718 UTCWARNING: Geomagnetic K-index of 4 expectedValid From: 2026 Mar 20 0719 UTCValid To: 2026 Mar 20 1500 UTCWarning Condition: OnsetNOAA Space Weather Scale descriptions can be found atwww.swpc.noaa.gov/noaa-scales-explanationPotential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.Induced Currents - Weak power grid fluctuations can occur.Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.
Local 3/19/2026, 4:59:20 AM
UTC 2026-03-19T04:59:20.403Z
Space Weather Message Code: ALTEF3Serial Number: 3651Issue Time: 2026 Mar 19 0459 UTCCONTINUED ALERT: Electron 2MeV Integral Flux exceeded 1000pfuContinuation of Serial Number: 3650Begin Time: 2026 Mar 15 1630 UTCYesterday Maximum 2MeV Flux: 2949 pfuPotential Impacts: Satellite systems may experience significant charging resulting in increased risk to satellite systems.