Space Weather Message Code: WATA20 Serial Number: 798 Issue Time: 2017 Sep 24 2110 UTC WATCH: Geomagnetic Storm Category G1 Predicted Highest Storm Level Predicted by Day: Sep 25: None (Below G1) Sep 26: None (Below G1) Sep 27: G1 (Minor) THIS SUPERSEDES ANY/ALL PRIOR WATCHES IN EFFECT 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.

Space Weather Message Code: WARK04 Serial Number: 3326 Issue Time: 2017 Sep 20 0353 UTC WARNING: Geomagnetic K-index of 4 expected Valid From: 2017 Sep 20 0352 UTC Valid To: 2017 Sep 20 1200 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: 3325 Issue Time: 2017 Sep 18 2311 UTC EXTENDED WARNING: Geomagnetic K-index of 4 expected Extension to Serial Number: 3324 Valid From: 2017 Sep 14 1310 UTC Now Valid Until: 2017 Sep 19 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 65 degrees Geomagnetic Latitude. Induced Currents –

Space Weather Message Code: ALTK05 Serial Number: 1165 Issue Time: 2017 Sep 18 0856 UTC ALERT: Geomagnetic K-index of 5 Threshold Reached: 2017 Sep 18 0856 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: WARK04 Serial Number: 3324 Issue Time: 2017 Sep 18 0855 UTC EXTENDED WARNING: Geomagnetic K-index of 4 expected Extension to Serial Number: 3323 Valid From: 2017 Sep 14 1310 UTC Now Valid Until: 2017 Sep 18 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: WARK05 Serial Number: 1407 Issue Time: 2017 Sep 18 0238 UTC WARNING: Geomagnetic K-index of 5 expected Valid From: 2017 Sep 18 0235 UTC Valid To: 2017 Sep 18 0900 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

Space Weather Message Code: WARK04 Serial Number: 3322 Issue Time: 2017 Sep 17 2343 UTC EXTENDED WARNING: Geomagnetic K-index of 4 expected Extension to Serial Number: 3321 Valid From: 2017 Sep 14 1310 UTC Now Valid Until: 2017 Sep 18 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 65 degrees Geomagnetic Latitude. Induced Currents –

Space Weather Message Code: WARK04 Serial Number: 3321 Issue Time: 2017 Sep 17 1147 UTC EXTENDED WARNING: Geomagnetic K-index of 4 expected Extension to Serial Number: 3320 Valid From: 2017 Sep 14 1310 UTC Now Valid Until: 2017 Sep 17 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: WARK04 Serial Number: 3320 Issue Time: 2017 Sep 16 1517 UTC EXTENDED WARNING: Geomagnetic K-index of 4 expected Extension to Serial Number: 3319 Valid From: 2017 Sep 14 1310 UTC Now Valid Until: 2017 Sep 17 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 65 degrees Geomagnetic Latitude. Induced Currents –

Space Weather Message Code: WARK05 Serial Number: 1406 Issue Time: 2017 Sep 16 1458 UTC EXTENDED WARNING: Geomagnetic K-index of 5 expected Extension to Serial Number: 1405 Valid From: 2017 Sep 14 1445 UTC Now Valid Until: 2017 Sep 17 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 60 degrees Geomagnetic Latitude. Induced Currents –