Winter's Last Hurrah (with any luck)

This map shows a classic winter weather pattern, with the key feature highlighted with the red line. It is a strong trough parked over southeast Canada, trailing a cold front southward and westward across the northern Gulf of Mexico. In the wake of the front, a cold Arctic ridge has sunk southward across most of the central and eastern continental United States.

The computer models are forecasting a significant pattern change by mid-late next week. They all forecast the SE Canada trough to move away and be replaced by a ridge, with another strong trough digging into the western United States. The combination of the counterclockwise flow around the trough in the West and clockwise flow around the ridge in the east will draw moist, unstable air northward from the Gulf of Mexico (which is currently supressed to the south of the cold front) and possibly signal the start of the spring severe thunderstorm season.