Alerts Issued in September 2018


Space Weather Message Code: WARK05
Serial Number: 1494
Issue Time: 2018 Sep 11 1110 UTC

EXTENDED WARNING: Geomagnetic K-index of 5 expected
Extension to Serial Number: 1493
Valid From: 2018 Sep 11 0423 UTC
Now Valid Until: 2018 Sep 11 2100 UTC
Warning Condition: persistence
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: WARK06
Serial Number: 424
Issue Time: 2018 Sep 11 1110 UTC

EXTENDED WARNING: Geomagnetic K-Index of 6 expected
Extension to Serial Number: 423
Valid From: 2018 Sep 11 0805 UTC
Now Valid Until: 2018 Sep 11 1500 UTC
Warning Condition: persistence
www.swpc.noaa.gov/noaa-scales-explanation
Potential 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.


Space Weather Message Code: WARK04
Serial Number: 3530
Issue Time: 2018 Sep 11 1110 UTC

EXTENDED WARNING: Geomagnetic K-index of 4 expected
Extension to Serial Number: 3529
Valid From: 2018 Sep 10 1610 UTC
Now Valid Until: 2018 Sep 11 2359 UTC
Warning Condition: Persistence
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: ALTK06
Serial Number: 469
Issue Time: 2018 Sep 11 1050 UTC

ALERT: Geomagnetic K-index of 6
Threshold Reached: 2018 Sep 11 1050 UTC
Synoptic Period: 0900-1200 UTC
Active Warning: Yes
NOAA Scale: G2 - Moderate
www.swpc.noaa.gov/noaa-scales-explanation
Potential 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.


Space Weather Message Code: ALTK05
Serial Number: 1240
Issue Time: 2018 Sep 11 1008 UTC

ALERT: Geomagnetic K-index of 5
Threshold Reached: 2018 Sep 11 1008 UTC
Synoptic Period: 0900-1200 UTC
Active Warning: Yes
NOAA Scale: G1 - Minor
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: ALTK06
Serial Number: 468
Issue Time: 2018 Sep 11 0817 UTC

ALERT: Geomagnetic K-index of 6
Threshold Reached: 2018 Sep 11 0817 UTC
Synoptic Period: 0600-0900 UTC
Active Warning: Yes
NOAA Scale: G2 - Moderate
www.swpc.noaa.gov/noaa-scales-explanation
Potential 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.


Space Weather Message Code: WARK06
Serial Number: 423
Issue Time: 2018 Sep 11 0804 UTC

WARNING: Geomagnetic K-Index of 6 expected
Valid From: 2018 Sep 11 0805 UTC
Valid To: 2018 Sep 11 1200 UTC
Warning Condition: Onset
NOAA Scale: G2 - Moderate
www.swpc.noaa.gov/noaa-scales-explanation
Potential 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.


Space Weather Message Code: ALTK05
Serial Number: 1239
Issue Time: 2018 Sep 11 0739 UTC

ALERT: Geomagnetic K-index of 5
Threshold Reached: 2018 Sep 11 0739 UTC
Synoptic Period: 0600-0900 UTC
Active Warning: Yes
NOAA Scale: G1 - Minor
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: ALTK05
Serial Number: 1238
Issue Time: 2018 Sep 11 0437 UTC

ALERT: Geomagnetic K-index of 5
Threshold Reached: 2018 Sep 11 0436 UTC
Synoptic Period: 0300-0600 UTC
Active Warning: Yes
NOAA Scale: G1 - Minor
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: WARK04
Serial Number: 3529
Issue Time: 2018 Sep 11 0425 UTC

EXTENDED WARNING: Geomagnetic K-index of 4 expected
Extension to Serial Number: 3528
Valid From: 2018 Sep 10 1610 UTC
Now Valid Until: 2018 Sep 11 1800 UTC
Warning Condition: Persistence
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: WARK05
Serial Number: 1493
Issue Time: 2018 Sep 11 0424 UTC

WARNING: Geomagnetic K-index of 5 expected
Valid From: 2018 Sep 11 0423 UTC
Valid To: 2018 Sep 11 1200 UTC
Warning Condition: Onset
NOAA Scale: G1 - Minor
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: ALTK05
Serial Number: 1237
Issue Time: 2018 Sep 10 2344 UTC

ALERT: Geomagnetic K-index of 5
Threshold Reached: 2018 Sep 10 2344 UTC
Synoptic Period: 2100-2400 UTC
Active Warning: Yes
NOAA Scale: G1 - Minor
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: ALTK05
Serial Number: 1236
Issue Time: 2018 Sep 10 2101 UTC

ALERT: Geomagnetic K-index of 5
Threshold Reached: 2018 Sep 10 2059 UTC
Synoptic Period: 1800-2100 UTC
Active Warning: Yes
NOAA Scale: G1 - Minor
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: WARK04
Serial Number: 3528
Issue Time: 2018 Sep 10 2036 UTC

EXTENDED WARNING: Geomagnetic K-index of 4 expected
Extension to Serial Number: 3527
Valid From: 2018 Sep 10 1610 UTC
Now Valid Until: 2018 Sep 11 0600 UTC
Warning Condition: Persistence
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: WARK05
Serial Number: 1492
Issue Time: 2018 Sep 10 2036 UTC

EXTENDED WARNING: Geomagnetic K-index of 5 expected
Extension to Serial Number: 1491
Valid From: 2018 Sep 10 1730 UTC
Now Valid Until: 2018 Sep 11 0300 UTC
Warning Condition: Persistence
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: ALTK05
Serial Number: 1235
Issue Time: 2018 Sep 10 1745 UTC

ALERT: Geomagnetic K-index of 5
Threshold Reached: 2018 Sep 10 1745 UTC
Synoptic Period: 1500-1800 UTC
Active Warning: Yes
NOAA Scale: G1 - Minor
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: 2074
Issue Time: 2018 Sep 10 1733 UTC

ALERT: Geomagnetic K-index of 4
Threshold Reached: 2018 Sep 10 1733 UTC
Synoptic Period: 1500-1800 UTC
Active Warning: Yes
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: WARK05
Serial Number: 1491
Issue Time: 2018 Sep 10 1729 UTC

WARNING: Geomagnetic K-index of 5 expected
Valid From: 2018 Sep 10 1730 UTC
Valid To: 2018 Sep 10 2100 UTC
Warning Condition: Onset
NOAA Scale: G1 - Minor
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: WARK04
Serial Number: 3527
Issue Time: 2018 Sep 10 1611 UTC

WARNING: Geomagnetic K-index of 4 expected
Valid From: 2018 Sep 10 1610 UTC
Valid To: 2018 Sep 10 2300 UTC
Warning Condition: Onset
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: WATA30
Serial Number: 175
Issue Time: 2018 Sep 09 2030 UTC

WATCH: Geomagnetic Storm Category G2 Predicted
Highest Storm Level Predicted by Day:
Sep 10: None (Below G1) Sep 11: G2 (Moderate) Sep 12: G1 (Minor)
THIS SUPERSEDES ANY/ALL PRIOR WATCHES IN EFFECT
www.swpc.noaa.gov/noaa-scales-explanation
Potential 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.


Space Weather Message Code: WATA20
Serial Number: 836
Issue Time: 2018 Sep 09 1953 UTC

WATCH: Geomagnetic Storm Category G1 Predicted
Highest Storm Level Predicted by Day:
Sep 10: None (Below G1) Sep 11: G1 (Minor) Sep 12: G1 (Minor)
THIS SUPERSEDES ANY/ALL PRIOR WATCHES IN EFFECT
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: 835
Issue Time: 2018 Sep 08 2127 UTC

WATCH: Geomagnetic Storm Category G1 Predicted
Highest Storm Level Predicted by Day:
Sep 09: None (Below G1) Sep 10: None (Below G1) Sep 11: G1 (Minor)
THIS SUPERSEDES ANY/ALL PRIOR WATCHES IN EFFECT
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: 2839
Issue Time: 2018 Sep 08 1812 UTC

ALERT: Electron 2MeV Integral Flux exceeded 1000pfu
Threshold Reached: 2018 Sep 08 1750 UTC
Station: GOES15
www.swpc.noaa.gov/noaa-scales-explanation
Potential Impacts: Satellite systems may experience significant charging resulting in increased risk to satellite systems.


Space Weather Message Code: ALTEF3
Serial Number: 2838
Issue Time: 2018 Sep 06 1839 UTC

ALERT: Electron 2MeV Integral Flux exceeded 1000pfu
Threshold Reached: 2018 Sep 06 1815 UTC
Station: GOES15
www.swpc.noaa.gov/noaa-scales-explanation
Potential Impacts: Satellite systems may experience significant charging resulting in increased risk to satellite systems.


Space Weather Message Code: WARK04
Serial Number: 3526
Issue Time: 2018 Sep 05 1527 UTC

WARNING: Geomagnetic K-index of 4 expected
Valid From: 2018 Sep 05 1526 UTC
Valid To: 2018 Sep 05 2100 UTC
Warning Condition: Onset
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: 2073
Issue Time: 2018 Sep 05 0239 UTC

ALERT: Geomagnetic K-index of 4
Threshold Reached: 2018 Sep 05 0239 UTC
Synoptic Period: 0000-0300 UTC
Active Warning: Yes
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: 3525
Issue Time: 2018 Sep 05 0208 UTC

WARNING: Geomagnetic K-index of 4 expected
Valid From: 2018 Sep 05 0210 UTC
Valid To: 2018 Sep 05 0600 UTC
Warning Condition: Onset
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: 2837
Issue Time: 2018 Sep 04 1706 UTC

CONTINUED ALERT: Electron 2MeV Integral Flux exceeded 1000pfu
Continuation of Serial Number: 2836
Begin Time: 2018 Aug 18 1410 UTC
Yesterday Maximum 2MeV Flux: 12435 pfu
www.swpc.noaa.gov/noaa-scales-explanation
Potential Impacts: Satellite systems may experience significant charging resulting in increased risk to satellite systems.


Space Weather Message Code: ALTEF3
Serial Number: 2836
Issue Time: 2018 Sep 03 0946 UTC

CONTINUED ALERT: Electron 2MeV Integral Flux exceeded 1000pfu
Continuation of Serial Number: 2835
Begin Time: 2018 Aug 18 1410 UTC
Yesterday Maximum 2MeV Flux: 16682 pfu
www.swpc.noaa.gov/noaa-scales-explanation
Potential Impacts: Satellite systems may experience significant charging resulting in increased risk to satellite systems.


Space Weather Message Code: ALTEF3
Serial Number: 2835
Issue Time: 2018 Sep 02 0900 UTC

CONTINUED ALERT: Electron 2MeV Integral Flux exceeded 1000pfu
Continuation of Serial Number: 2834
Begin Time: 2018 Aug 18 1410 UTC
Yesterday Maximum 2MeV Flux: 20417 pfu
www.swpc.noaa.gov/noaa-scales-explanation
Potential Impacts: Satellite systems may experience significant charging resulting in increased risk to satellite systems.


Space Weather Message Code: ALTEF3
Serial Number: 2834
Issue Time: 2018 Sep 01 0901 UTC

CONTINUED ALERT: Electron 2MeV Integral Flux exceeded 1000pfu
Continuation of Serial Number: 2833
Begin Time: 2018 Aug 18 1410 UTC
Yesterday Maximum 2MeV Flux: 31634 pfu
www.swpc.noaa.gov/noaa-scales-explanation
Potential Impacts: Satellite systems may experience significant charging resulting in increased risk to satellite systems.