Space Weather Message Code: WARK04 Serial Number: 3249 Issue Time: 2017 Jul 17 1537 UTC EXTENDED WARNING: Geomagnetic K-index of 4 expected Extension to Serial Number: 3248 Valid From: 2017 Jul 16 0520 UTC Now Valid Until: 2017 Jul 17 2300 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: 3248 Issue Time: 2017 Jul 17 0555 UTC EXTENDED WARNING: Geomagnetic K-index of 4 expected Extension to Serial Number: 3247 Valid From: 2017 Jul 16 0520 UTC Now Valid Until: 2017 Jul 17 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 –

Space Weather Message Code: WARK05 Serial Number: 1367 Issue Time: 2017 Jul 17 0528 UTC EXTENDED WARNING: Geomagnetic K-index of 5 expected Extension to Serial Number: 1366 Valid From: 2017 Jul 16 0520 UTC Now Valid Until: 2017 Jul 17 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 60 degrees Geomagnetic Latitude. Induced Currents –

Space Weather Message Code: ALTK05 Serial Number: 1125 Issue Time: 2017 Jul 16 2155 UTC ALERT: Geomagnetic K-index of 5 Threshold Reached: 2017 Jul 16 2150 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: WARK05 Serial Number: 1366 Issue Time: 2017 Jul 16 2023 UTC EXTENDED WARNING: Geomagnetic K-index of 5 expected Extension to Serial Number: 1365 Valid From: 2017 Jul 16 0520 UTC Now Valid Until: 2017 Jul 17 0600 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 60 degrees Geomagnetic Latitude. Induced Currents –

Space Weather Message Code: ALTK06 Serial Number: 437 Issue Time: 2017 Jul 16 1958 UTC ALERT: Geomagnetic K-index of 6 Threshold Reached: 2017 Jul 16 1957 UTC Synoptic Period: 1800-2100 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: 389 Issue Time: 2017 Jul 16 1950 UTC WARNING: Geomagnetic K-Index of 6 expected Valid From: 2017 Jul 16 1950 UTC Valid To: 2017 Jul 17 0300 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: 1124 Issue Time: 2017 Jul 16 1655 UTC ALERT: Geomagnetic K-index of 5 Threshold Reached: 2017 Jul 16 1654 UTC Synoptic Period: 1500-1800 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: 436 Issue Time: 2017 Jul 16 1455 UTC ALERT: Geomagnetic K-index of 6 Threshold Reached: 2017 Jul 16 1454 UTC Synoptic Period: 1200-1500 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: 1123 Issue Time: 2017 Jul 16 1309 UTC ALERT: Geomagnetic K-index of 5 Threshold Reached: 2017 Jul 16 1308 UTC Synoptic Period: 1200-1500 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.