On Feb 26 SWPC issued a G3 (Strong) geomagnetic storm watch for Feb 27 in anticipation of the arrival of 2 coronal mass ejections (CMEs) from Feb 25 and 26, the latter of which was associated with a M6.2 flare from Active Region 2329. Wind speeds were already predicted to be elevated in response to a recurrent, coronal hole high speed stream. On Feb 26 at 12:33 pm EST, a sudden impulse was first observed at the DSCOVR satellite, indicating the imminent arrival of the CME(s). SWPC officially observed G3 (Strong) conditions across a global network of real-time magnetometers on Feb 27 at 1:00 am EST. G3 conditions are expected through most of the remainder of Feb 27. G2 (Moderate) conditions are likely for Feb 28 with ongoing storming.
NOAA Scales mini
HF Radio: Weak or minor degradation of HF radio communication on sunlit side, occasional loss of radio contact.
Navigation: Low-frequency navigation signals degraded for brief intervals.
More about the NOAA Space Weather Scales
Navigation: Low-frequency navigation signals degraded for brief intervals.
G3 (Strong) Geomagnetic Storm Conditions Observed on Feb 27
G3 (Strong) Geomagnetic Storm Conditions Observed on Feb 27