By Joseph D’Aleo, CCM

It started with a dump of frigid arctic air last week that brought single digit and sub-zero temperatures across the north and record cold and even flurries to the deep south including Florida. Then a series of storms began to dive out of the trough that has been so persistent near Alaska into California bringing very heavy flooding rains, hurricane force winds and mountain snows measured in yards not feet or inches.

As the cold arctic high moved off the east coast and the western storms came east, southerly winds pumped warm air north shattering records for 138 cities in the plains and midwest Monday and many cities in the east Tuesday. With the warm air came tornadoes as far north as Wisconsin. Tornadoes in the period from the late fall to the late spring are more common in La Nina years. But this warm spell will be short lived as the regime change proceeds. A ridge will gradually replace the trough off the west coast which will shut off the flow of Pacific air into North America and allow the arctic air trapped air up by Alaska and Northern Canada and across the arctic ice to Siberia to spread south into the lower 48 states. Snow will start to rebuild across the north this week with a storm and the east coast may have a nor’easter early next week. Cold air will follow and deepen as the month progresses with some of the coldest air in years possible for much of the nation.