Space Weather Message Code: ALTK04 Serial Number: 2075 Issue Time: 2018 Sep 13 0152 UTC ALERT: Geomagnetic K-index of 4 Threshold Reached: 2018 Sep 13 0152 UTC Synoptic Period: 0000-0300 UTC Active Warning: Yes 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

Space Weather Message Code: WARK04 Serial Number: 3532 Issue Time: 2018 Sep 12 2357 UTC WARNING: Geomagnetic K-index of 4 expected Valid From: 2018 Sep 13 0000 UTC Valid To: 2018 Sep 13 0600 UTC Warning Condition: Onset 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

Space Weather Message Code: WARK04 Serial Number: 3531 Issue Time: 2018 Sep 11 2344 UTC EXTENDED WARNING: Geomagnetic K-index of 4 expected Extension to Serial Number: 3530 Valid From: 2018 Sep 10 1610 UTC Now Valid Until: 2018 Sep 12 0900 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: 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 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: 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 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: 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 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: 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 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: 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 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: 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 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: 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 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.