Space Weather Message Code: ALTK07 Serial Number: 120 Issue Time: 2023 Feb 27 0802 UTC ALERT: Geomagnetic K-index of 7 Threshold Reached: 2023 Feb 27 0800 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: 504 Issue Time: 2023 Feb 27 0658 UTC ALERT: Geomagnetic K-index of 6 Threshold Reached: 2023 Feb 27 0657 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: ALTK06 Serial Number: 503 Issue Time: 2023 Feb 27 0525 UTC ALERT: Geomagnetic K-index of 6 Threshold Reached: 2023 Feb 27 0522 UTC Synoptic Period: 0300-0600 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: 1433 Issue Time: 2023 Feb 27 0408 UTC ALERT: Geomagnetic K-index of 5 Threshold Reached: 2023 Feb 27 0400 UTC Synoptic Period: 0300-0600 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: ALTK05 Serial Number: 1432 Issue Time: 2023 Feb 27 0253 UTC ALERT: Geomagnetic K-index of 5 Threshold Reached: 2023 Feb 27 0248 UTC Synoptic Period: 0000-0300 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: ALTK06 Serial Number: 502 Issue Time: 2023 Feb 26 2345 UTC ALERT: Geomagnetic K-index of 6 Threshold Reached: 2023 Feb 26 2340 UTC Synoptic Period: 2100-2400 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: WARK06 Serial Number: 470 Issue Time: 2023 Feb 26 2233 UTC WARNING: Geomagnetic K-Index of 6 expected Valid From: 2023 Feb 26 2232 UTC Valid To: 2023 Feb 27 0900 UTC Warning Condition: Onset 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

Space Weather Message Code: ALTK05 Serial Number: 1431 Issue Time: 2023 Feb 26 2145 UTC ALERT: Geomagnetic K-index of 5 Threshold Reached: 2023 Feb 26 2145 UTC Synoptic Period: 2100-2400 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: ALTK05 Serial Number: 1430 Issue Time: 2023 Feb 26 2055 UTC ALERT: Geomagnetic K-index of 5 Threshold Reached: 2023 Feb 26 2055 UTC Synoptic Period: 1800-2100 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: WARK05 Serial Number: 1747 Issue Time: 2023 Feb 26 1936 UTC WARNING: Geomagnetic K-index of 5 expected Valid From: 2023 Feb 26 1935 UTC Valid To: 2023 Feb 27 1500 UTC Warning Condition: Onset 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