Let's fast forward to Thursday and Friday. At this time, a northward bowing of the jet stream over the Eastern states will coincide with its southward buckling in the West. Unusual warmth will break out from the Mississippi Valley to the Eastern Seaboard. At the same time, chilly air will dip southward over the West Coast through the Rockies accompanied in some areas by rain and even snow.
Story by AccuWeather.com Senior Meteorologist Jim Andrews.