The MODIS instrument aboard NASA’s Aqua satellite captured this true-color image of a large low pressure system spinning in the Gulf of Alaska on August 17, 2004 at 22:45 UTC. This area of the world is famous for strong, persisent low pressure systems because of the persistent flow of semi-permanent pressure systems north (the polar easterlies) and south (the subtropical high) of the area.
Winter turned fierce in the opening weeks of 2009, and part of the reason for the cold snaps and winter storms came from big changes in the atmosphere about 20 kilometers above the Earth.