ALERT: Geomagnetic Storm Active Warning: Yes

Space Weather Message Code: ALTK04
Serial Number: 1507
Issue Time: 2011 Apr 23 1103 UTC

ALERT: Geomagnetic K-index of 4
Threshold Reached: 2011 Apr 23 1100 UTC
Synoptic Period: 0300-0600 UTC
Station: Boulder
Active Warning: Yes