If the skies are clear, go outside- you just might see the aurora! Over the past 24 hours, NOAA SWPC has been warning that we may see a geomagnetic storm. Because the intensities of such storms are hard to predict, and because the recent spate of storms has been so weak, I have been very skeptical that we would see a “good one”, but right now, we’re seeing all the earmarks of a “real” space weather storm- one worth paying attention to! The storm has reached “G4” on NOAA’s geomagnetic storm scale, which is the 2nd most severe category. Here’s a quick summary of the last few hours:
|KP||8||Very high activity, 9 is the highest that the Kp index can get!|
|DST||-150nT||More negative is stronger; watch to see if we hit -300nT|
|Solar Wind Speed||~700km/s||Almost twice as fast as usual.|
|Solar Magnetic Field||BZ ~= -30nT||Strength of magnetic field in solar wind, more negative means more energy delivered to the Earth & aurora.|
So far, these are the kinds of numbers you associate with strong, possibly damaging storms. It will be interesting to watch the DST number; if it drops to -300nT, we’ve hit “super storm” status.
Watch the skies this evening!