G2 Geomagnetic Storm Observed. G1 Conditions Continue
A G2 (Moderate) Geomagnetic Storm Alert was observed on December 21, 2016 at 1613 UTC (11:13 am ET). Conditions are expected to remain elevated with G1 (Minor) storms through 22/1500 UTC due to continued coronal hole high speed stream effects.
Solar Wind Speed: 646 km/sec
Solar Wind Magnetic Fields: Bt 5 nT, Bz -2 nT
THE SOLAR WIND HAS ARRIVED: Earth is inside a stream of solar wind blowing out of a huge hole in the sun's atmosphere. NOAA forecasters estimate a 60% chance of G1-class geomagnetic storms on Dec. 22nd. High-latitude sky watchers should be alert for auroras, especially during the hours around local midnight.
Geomagnetic Storming Observed
An anticipated coronal hole stream containing periods of southward Bz is now moving past Earth. A period of Moderate (G2) geomagnetic storming was observed at higher latitudes on Wednesday.
A minor (G1) storm watch will remain in effect over the next 24 hours.
EXTENDED WARNING: Geomagnetic K-index of 5 expected Valid From: 2016 Dec 21 1604 UTC Now Valid Until: 2016 Dec 22 1500 UTC Warning Condition: Persistence
Images credit: NOAA/SWPC & NASA/SDO
