Geomagnetic activity

Space Weather Message Code: WARK05
Serial Number: 2272
Issue Time: 2026 Oct 30 2311 UTC

WARNING: Geomagnetic K-index of 5 expected 
Valid From: 2026 Oct 30 2310 UTC
Valid To: 2026 Oct 31 0600 UTC
Warning Conditions: Onset
Noaa Scale: G1 - Minor
Comment: 

NOAA Scale: G1 - Minor

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential 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.

Space Weather Message Code: ALTK04
Serial Number: 2695
Issue Time: 2026 Oct 30 2240 UTC

ALERT: Geomagnetic K-index of 4 
Threshold Reached: 2026 Oct 30 2235 UTC
Synoptic Period: 2100-2400
Active Warning: YES
Comment: 

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential 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.

Space Weather Message Code: WARK04
Serial Number: 5444
Issue Time: 2026 Oct 30 2224 UTC

WARNING: Geomagnetic K-index of 4 expected 
Valid From: 2026 Oct 30 2223 UTC
Valid To: 2026 Oct 31 1200 UTC
Warning Conditions: Onset
Comment: 

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential 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.

Space Weather Message Code: ALTEF3
Serial Number: 3762
Issue Time: 2026 Oct 30 1459 UTC

CONTINUED ALERT: Electron 2MeV Integral Flux exceeded 1,000pfu
Continuation of Serial Number: 3761
Begin Time: 2026 Oct 23 1140 UTC

Yesterday Maximum 2MeV Flux: 1228 pfu
Max time: 2026 Oct 29 1630 UTC

Space Weather Message Code: WATA20
Serial Number: 1134
Issue Time: 2026 Oct 29 1910 UTC

WATCH: Geomagnetic Storm Category G1 Predicted 
Highest Storm Level Predicted by Day:
Oct 30:  None (Below G1)   Oct 31:  G1 (Minor)   Nov 01:  G1 (Minor)   
THIS SUPERSEDES ANY/ALL PRIOR WATCHES IN EFFECT
Comment: 

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential 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.

Space Weather Message Code: ALTEF3
Serial Number: 3761
Issue Time: 2026 Oct 29 1614 UTC

CONTINUED ALERT: Electron 2MeV Integral Flux exceeded 1,000pfu
Continuation of Serial Number: 3760
Begin Time: 2026 Oct 23 1140 UTC

Yesterday Maximum 2MeV Flux: 2493 pfu
Max time: 2026 Oct 28 1805 UTC

Space Weather Message Code: WATA20
Serial Number: 1133
Issue Time: 2026 Oct 28 1638 UTC

WATCH: Geomagnetic Storm Category G1 Predicted 
Highest Storm Level Predicted by Day:
Oct 29:  None (Below G1)   Oct 30:  None (Below G1)   Oct 31:  G1 (Minor)   
THIS SUPERSEDES ANY/ALL PRIOR WATCHES IN EFFECT
Comment: G1 (Minor) geomagnetic storms are likely on 31 Oct primarily due to recurrent, positive polarity coronal hole high speed stream effects.


NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential 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.

Space Weather Message Code: ALTEF3
Serial Number: 3760
Issue Time: 2026 Oct 28 0923 UTC

CONTINUED ALERT: Electron 2MeV Integral Flux exceeded 1,000pfu
Continuation of Serial Number: 3759
Begin Time: 2026 Oct 23 1140 UTC

Yesterday Maximum 2MeV Flux: 1789 pfu
Max time: 2026 Oct 27 1715 UTC

Space Weather Message Code: ALTEF3
Serial Number: 3759
Issue Time: 2026 Oct 27 1138 UTC

CONTINUED ALERT: Electron 2MeV Integral Flux exceeded 1,000pfu
Continuation of Serial Number: 3758
Begin Time: 2026 Oct 23 1140 UTC

Yesterday Maximum 2MeV Flux: 3304 pfu
Max time: 2026 Oct 26 1105 UTC

Space Weather Message Code: ALTEF3
Serial Number: 3758
Issue Time: 2026 Oct 26 0517 UTC

CONTINUED ALERT: Electron 2MeV Integral Flux exceeded 1,000pfu
Continuation of Serial Number: 3757
Begin Time: 2026 Oct 23 1140 UTC

Yesterday Maximum 2MeV Flux: 2864 pfu
Max time: 2026 Oct 25 1820 UTC

Space Weather Message Code: ALTEF3
Serial Number: 3757
Issue Time: 2026 Oct 25 0927 UTC

CONTINUED ALERT: Electron 2MeV Integral Flux exceeded 1,000pfu
Continuation of Serial Number: 3756
Begin Time: 2026 Oct 23 1140 UTC

Yesterday Maximum 2MeV Flux: 3259 pfu
Max time: 2026 Oct 24 1530 UTC

Space Weather Message Code: ALTEF3
Serial Number: 3756
Issue Time: 2026 Oct 24 0904 UTC

CONTINUED ALERT: Electron 2MeV Integral Flux exceeded 1,000pfu
Continuation of Serial Number: 3755
Begin Time: 2026 Oct 23 1140 UTC

Yesterday Maximum 2MeV Flux: 3169 pfu
Max time: 2026 Oct 23 1540 UTC

Space Weather Message Code: ALTK04
Serial Number: 2694
Issue Time: 2026 Oct 23 1955 UTC

ALERT: Geomagnetic K-index of 4 
Threshold Reached: 2026 Oct 23 1953 UTC
Synoptic Period: 1800-2100
Active Warning: YES
Comment: 

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential 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.

Space Weather Message Code: WARK04
Serial Number: 5443
Issue Time: 2026 Oct 23 1927 UTC

WARNING: Geomagnetic K-index of 4 expected 
Valid From: 2026 Oct 23 1926 UTC
Valid To: 2026 Oct 24 0900 UTC
Warning Conditions: Onset
Comment: 

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential 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.

Space Weather Message Code: ALTEF3
Serial Number: 3755
Issue Time: 2026 Oct 23 1147 UTC

ALERT: Electron 2MeV Integral Flux exceeded 1,000pfu 
Threshold Reached: 2026 Oct 23 1140 UTC
Station: GOES-19
Comment: 

Space Weather Message Code: WARK04
Serial Number: 5442
Issue Time: 2026 Oct 22 2021 UTC

EXTENDED WARNING: Geomagnetic K-index of 4 expected
Extension to Serial Number: 5441
Valid From: 2026 Oct 21 1616 UTC
Now Valid Until: 2026 Oct 23 0300 UTC
Warning Condition: Persistence


NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential 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.

Space Weather Message Code: WARK04
Serial Number: 5441
Issue Time: 2026 Oct 22 1648 UTC

EXTENDED WARNING: Geomagnetic K-index of 4 expected
Extension to Serial Number: 5440
Valid From: 2026 Oct 21 1616 UTC
Now Valid Until: 2026 Oct 22 2100 UTC
Warning Condition: Persistence


NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential 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.

Space Weather Message Code: WARK04
Serial Number: 5440
Issue Time: 2026 Oct 22 1424 UTC

EXTENDED WARNING: Geomagnetic K-index of 4 expected
Extension to Serial Number: 5439
Valid From: 2026 Oct 21 1616 UTC
Now Valid Until: 2026 Oct 22 1800 UTC
Warning Condition: Persistence


NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential 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.

Space Weather Message Code: WARK04
Serial Number: 5439
Issue Time: 2026 Oct 22 0532 UTC

EXTENDED WARNING: Geomagnetic K-index of 4 expected
Extension to Serial Number: 5438
Valid From: 2026 Oct 21 1616 UTC
Now Valid Until: 2026 Oct 22 1500 UTC
Warning Condition: Persistence


NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential 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.

Space Weather Message Code: ALTK05
Serial Number: 2058
Issue Time: 2026 Oct 22 0003 UTC

ALERT: Geomagnetic K-index of 5 
Threshold Reached: 2026 Oct 21 2359 UTC
Synoptic Period: 2100-2400
Active Warning: YES
Noaa Scale: G1 - Minor
Comment: 

NOAA Scale: G1 - Minor

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential 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.

Space Weather Message Code: WARK05
Serial Number: 2271
Issue Time: 2026 Oct 21 2228 UTC

WARNING: Geomagnetic K-index of 5 expected 
Valid From: 2026 Oct 21 2227 UTC
Valid To: 2026 Oct 22 0900 UTC
Warning Conditions: Onset
Noaa Scale: G1 - Minor
Comment: 

NOAA Scale: G1 - Minor

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential 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.

Space Weather Message Code: ALTK04
Serial Number: 2693
Issue Time: 2026 Oct 21 2130 UTC

ALERT: Geomagnetic K-index of 4 
Threshold Reached: 2026 Oct 21 2059 UTC
Synoptic Period: 1800-2100
Active Warning: YES
Comment: 

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential 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.

Space Weather Message Code: WARK04
Serial Number: 5438
Issue Time: 2026 Oct 21 1617 UTC

WARNING: Geomagnetic K-index of 4 expected 
Valid From: 2026 Oct 21 1616 UTC
Valid To: 2026 Oct 22 0600 UTC
Warning Conditions: Onset
Comment: 

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential 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.

Space Weather Message Code: ALTK04
Serial Number: 2692
Issue Time: 2026 Oct 21 0429 UTC

ALERT: Geomagnetic K-index of 4 
Threshold Reached: 2026 Oct 21 0429 UTC
Synoptic Period: 0300-0600
Active Warning: YES
Comment: 

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential 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.

Space Weather Message Code: WARK04
Serial Number: 5437
Issue Time: 2026 Oct 21 0205 UTC

WARNING: Geomagnetic K-index of 4 expected 
Valid From: 2026 Oct 21 0204 UTC
Valid To: 2026 Oct 21 1200 UTC
Warning Conditions: Onset
Comment: 

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential 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.

Space Weather Message Code: WATA20
Serial Number: 1132
Issue Time: 2026 Oct 20 1912 UTC

WATCH: Geomagnetic Storm Category G1 Predicted 
Highest Storm Level Predicted by Day:
Oct 21:  G1 (Minor)   Oct 22:  None (Below G1)   Oct 23:  None (Below G1)   
THIS SUPERSEDES ANY/ALL PRIOR WATCHES IN EFFECT
Comment: 

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential 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.

Space Weather Message Code: SUM10R
Serial Number: 930
Issue Time: 2026 Oct 19 0909 UTC

SUMMARY: 10cm Radio Burst 
Begin Time: 2026 Oct 19 0858 UTC
Maximum Time: 2026 Oct 19 0859 UTC
End Time: 2026 Oct 19 0859 UTC
Peak Flux: 430 sfu
Duration: 1 minutes
Latest Penticton Noon Flux: 137 sfu
Comment: 

Space Weather Message Code: WATA20
Serial Number: 1131
Issue Time: 2026 Oct 18 1724 UTC

WATCH: Geomagnetic Storm Category G1 Predicted 
Highest Storm Level Predicted by Day:
Oct 19:  G1 (Minor)   Oct 20:  G1 (Minor)   Oct 21:  None (Below G1)   
THIS SUPERSEDES ANY/ALL PRIOR WATCHES IN EFFECT
Comment: 

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential 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.

Space Weather Message Code: WATA20
Serial Number: 1130
Issue Time: 2026 Oct 17 2014 UTC

WATCH: Geomagnetic Storm Category G1 Predicted 
Highest Storm Level Predicted by Day:
Oct 18:  None (Below G1)   Oct 19:  None (Below G1)   Oct 20:  G1 (Minor)   
THIS SUPERSEDES ANY/ALL PRIOR WATCHES IN EFFECT
Comment: 

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential 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.

Space Weather Message Code: ALTK04
Serial Number: 2691
Issue Time: 2026 Oct 16 1939 UTC

ALERT: Geomagnetic K-index of 4 
Threshold Reached: 2026 Oct 16 1940 UTC
Synoptic Period: 1800-2100
Active Warning: YES
Comment: 

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential 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.