Local 8/19/2026, 5:57:55 PM
UTC 2026-08-19T17:57:55.430Z
Space Weather Message Code: WARK04Serial Number: 5406Issue Time: 2026 Aug 19 1757 UTCEXTENDED WARNING: Geomagnetic K-index of 4 expected Extension to Serial Number: 5405 Valid From: 2026 Aug 17 2101 UTC Now Valid Until: 2026 Aug 20 0900 UTC Warning 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 8/19/2026, 5:45:36 AM
UTC 2026-08-19T05:45:36.950Z
Space Weather Message Code: ALTK05Serial Number: 2047Issue Time: 2026 Aug 19 0545 UTCALERT: Geomagnetic K-index of 5 Threshold Reached: 2026 Aug 19 0545 UTC Synoptic Period: 0300-0600 Active Warning: YES Noaa Scale: G1 - Minor Comment:NOAA 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 8/18/2026, 8:52:01 PM
UTC 2026-08-18T20:52:01.733Z
Space Weather Message Code: WARK04Serial Number: 5405Issue Time: 2026 Aug 18 2052 UTCEXTENDED WARNING: Geomagnetic K-index of 4 expected Extension to Serial Number: 5404 Valid From: 2026 Aug 17 2101 UTC Now Valid Until: 2026 Aug 19 1800 UTC Warning 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 8/18/2026, 8:45:07 PM
UTC 2026-08-18T20:45:07.963Z
Space Weather Message Code: ALTK05Serial Number: 2046Issue Time: 2026 Aug 18 2045 UTCALERT: Geomagnetic K-index of 5 Threshold Reached: 2026 Aug 18 2045 UTC Synoptic Period: 1800-2100 Active Warning: YES Noaa Scale: G1 - Minor Comment:NOAA 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 8/18/2026, 8:43:17 PM
UTC 2026-08-18T20:43:17.463Z
Space Weather Message Code: WARK05Serial Number: 2260Issue Time: 2026 Aug 18 2043 UTCWARNING: Geomagnetic K-index of 5 expected Valid From: 2026 Aug 18 2042 UTC Valid To: 2026 Aug 19 1200 UTC Warning Conditions: Onset Noaa Scale: G1 - Minor Comment:NOAA 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 8/18/2026, 2:31:43 PM
UTC 2026-08-18T14:31:43.380Z
Space Weather Message Code: WARK04Serial Number: 5404Issue Time: 2026 Aug 18 1431 UTCEXTENDED WARNING: Geomagnetic K-index of 4 expected Extension to Serial Number: 5403 Valid From: 2026 Aug 17 2101 UTC Now Valid Until: 2026 Aug 18 2359 UTC Warning 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 8/18/2026, 5:06:25 AM
UTC 2026-08-18T05:06:25.137Z
Space Weather Message Code: ALTK05Serial Number: 2045Issue Time: 2026 Aug 18 0506 UTCALERT: Geomagnetic K-index of 5 Threshold Reached: 2026 Aug 18 0505 UTC Synoptic Period: 0300-0600 Active Warning: YES Noaa Scale: G1 - Minor Comment:NOAA 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 8/18/2026, 2:27:43 AM
UTC 2026-08-18T02:27:43.313Z
Space Weather Message Code: WARK04Serial Number: 5403Issue Time: 2026 Aug 18 0227 UTCEXTENDED WARNING: Geomagnetic K-index of 4 expected Extension to Serial Number: 5402 Valid From: 2026 Aug 17 2101 UTC Now Valid Until: 2026 Aug 18 1500 UTC Warning 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 8/18/2026, 2:27:00 AM
UTC 2026-08-18T02:27:00.810Z
Space Weather Message Code: WARK05Serial Number: 2259Issue Time: 2026 Aug 18 0227 UTCWARNING: Geomagnetic K-index of 5 expected Valid From: 2026 Aug 18 0224 UTC Valid To: 2026 Aug 18 1200 UTC Warning Conditions: Onset Noaa Scale: G1 - Minor Comment:NOAA 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 8/17/2026, 10:46:24 PM
UTC 2026-08-17T22:46:24.740Z
Space Weather Message Code: WATA20Serial Number: 1121Issue Time: 2026 Aug 17 2246 UTCWATCH: Geomagnetic Storm Category G1 Predicted Highest Storm Level Predicted by Day: Aug 18: None (Below G1) Aug 19: G1 (Minor) Aug 20: None (Below G1) THIS SUPERSEDES ANY/ALL PRIOR WATCHES IN EFFECT Comment:NOAA 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.