Space Weather Message Code: WARK06 Serial Number: 379 Issue Time: 2017 Apr 22 0249 UTC WARNING: Geomagnetic K-Index of 6 expected Valid From: 2017 Apr 22 0245 UTC Valid To: 2017 Apr 22 0600 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: 1100 Issue Time: 2017 Apr 22 0238 UTC ALERT: Geomagnetic K-index of 5 Threshold Reached: 2017 Apr 22 0235 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: ALTK05 Serial Number: 1099 Issue Time: 2017 Apr 22 0001 UTC ALERT: Geomagnetic K-index of 5 Threshold Reached: 2017 Apr 21 2359 UTC Synoptic Period: 2100-0000 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: 1344 Issue Time: 2017 Apr 21 2157 UTC EXTENDED WARNING: Geomagnetic K-index of 5 expected Extension to Serial Number: 1343 Valid From: 2017 Apr 21 1920 UTC Now Valid Until: 2017 Apr 22 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 –

Space Weather Message Code: ALTK05 Serial Number: 1098 Issue Time: 2017 Apr 21 2039 UTC ALERT: Geomagnetic K-index of 5 Threshold Reached: 2017 Apr 21 2032 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: WATA30 Serial Number: 154 Issue Time: 2017 Apr 21 1925 UTC WATCH: Geomagnetic Storm Category G2 Predicted Highest Storm Level Predicted by Day: Apr 22: G1 (Minor) Apr 23: G2 (Moderate) Apr 24: 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 55 degrees Geomagnetic Latitude. Induced Currents

Space Weather Message Code: WARK05 Serial Number: 1343 Issue Time: 2017 Apr 21 1924 UTC WARNING: Geomagnetic K-index of 5 expected Valid From: 2017 Apr 21 1920 UTC Valid To: 2017 Apr 21 2359 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: ALTK04 Serial Number: 1974 Issue Time: 2017 Apr 21 1642 UTC ALERT: Geomagnetic K-index of 4 Threshold Reached: 2017 Apr 21 1638 UTC Synoptic Period: 1500-1800 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: 3210 Issue Time: 2017 Apr 21 1548 UTC WARNING: Geomagnetic K-index of 4 expected Valid From: 2017 Apr 21 1546 UTC Valid To: 2017 Apr 21 2359 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: WATA30 Serial Number: 153 Issue Time: 2017 Apr 20 1959 UTC WATCH: Geomagnetic Storm Category G2 Predicted Highest Storm Level Predicted by Day: Apr 21: None (Below G1) Apr 22: None (Below G1) Apr 23: G2 (Moderate) 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 55 degrees Geomagnetic Latitude.