Space Weather Message Code: WARK04 Serial Number: 4721 Issue Time: 2024 Oct 11 1144 UTC EXTENDED WARNING: Geomagnetic K-index of 4 expected Extension to Serial Number: 4720 Valid From: 2024 Oct 10 1350 UTC Now Valid Until: 2024 Oct 11 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 –

Space Weather Message Code: ALTK07 Serial Number: 176 Issue Time: 2024 Oct 11 1012 UTC ALERT: Geomagnetic K-index of 7 Threshold Reached: 2024 Oct 11 1012 UTC Synoptic Period: 0900-1200 UTC Active Warning: Yes NOAA Scale: G3 – Strong NOAA Space Weather Scale descriptions can be found at www.swpc.noaa.gov/noaa-scales-explanation Potential Impacts: Area of impact primarily poleward of 50 degrees Geomagnetic Latitude. Induced Currents – Power system voltage irregularities possible, false

Space Weather Message Code: ALTK06 Serial Number: 609 Issue Time: 2024 Oct 11 0939 UTC ALERT: Geomagnetic K-index of 6 Threshold Reached: 2024 Oct 11 0939 UTC Synoptic Period: 0900-1200 UTC Active Warning: Yes NOAA Scale: G2 – Moderate NOAA Space Weather Scale descriptions can be found at 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

Space Weather Message Code: ALTK05 Serial Number: 1671 Issue Time: 2024 Oct 11 0926 UTC ALERT: Geomagnetic K-index of 5 Threshold Reached: 2024 Oct 11 0925 UTC Synoptic Period: 0900-1200 UTC Active Warning: Yes 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.

Space Weather Message Code: ALTK08 Serial Number: 48 Issue Time: 2024 Oct 11 0848 UTC ALERT: Geomagnetic K-index of 8, 9- Threshold Reached: 2024 Oct 11 0848 UTC Synoptic Period: 0600-0900 UTC Active Warning: Yes NOAA Scale: G4 – Severe NOAA Space Weather Scale descriptions can be found at 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

Space Weather Message Code: ALTK07 Serial Number: 175 Issue Time: 2024 Oct 11 0742 UTC ALERT: Geomagnetic K-index of 7 Threshold Reached: 2024 Oct 11 0742 UTC Synoptic Period: 0600-0900 UTC Active Warning: Yes NOAA Scale: G3 – Strong NOAA Space Weather Scale descriptions can be found at www.swpc.noaa.gov/noaa-scales-explanation Potential Impacts: Area of impact primarily poleward of 50 degrees Geomagnetic Latitude. Induced Currents – Power system voltage irregularities possible, false

Space Weather Message Code: ALTK06 Serial Number: 608 Issue Time: 2024 Oct 11 0627 UTC ALERT: Geomagnetic K-index of 6 Threshold Reached: 2024 Oct 11 0619 UTC Synoptic Period: 0600-0900 UTC Active Warning: Yes NOAA Scale: G2 – Moderate NOAA Space Weather Scale descriptions can be found at 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

Space Weather Message Code: ALTK05 Serial Number: 1670 Issue Time: 2024 Oct 11 0616 UTC ALERT: Geomagnetic K-index of 5 Threshold Reached: 2024 Oct 11 0611 UTC Synoptic Period: 0600-0900 UTC Active Warning: Yes 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.

Space Weather Message Code: WARK07 Serial Number: 119 Issue Time: 2024 Oct 11 0516 UTC EXTENDED WARNING: Geomagnetic K-index of 7 or greater expected Extension to Serial Number: 118 Valid From: 2024 Oct 10 1541 UTC Now Valid Until: 2024 Oct 11 1200 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 50 degrees Geomagnetic Latitude. Induced

Space Weather Message Code: ALTK08 Serial Number: 47 Issue Time: 2024 Oct 11 0515 UTC ALERT: Geomagnetic K-index of 8, 9- Threshold Reached: 2024 Oct 11 0510 UTC Synoptic Period: 0300-0600 UTC Active Warning: Yes NOAA Scale: G4 – Severe NOAA Space Weather Scale descriptions can be found at 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