Pattern change is in the air for later December as the warm and dry pattern dominating the South reverses cold while dry zones in Texas to the Mid-South gain a storm track. The evolution of these scenarios is caused by a clash of frigid temperatures spreading across the West and Central U.S. beginning next weekend with the impressive warmth anchored over the Southeast. This pattern could last for awhile.
A cold air mass surges out of Canada and into the Rockies/Interior West the day before Christmas. Widespread snows accompany the big chill across the Rockies and into the Interior West. A storm forms on the strong cold front and drifts northeastward Dec. 25-26 and causes a large swath of snow from the Great Plains to the Great Lakes. Significant amount is likely. A large area of freezing rain causing an icing situation is possible in the Mid-South to southern Ohio Valley and possibly the Northeast States.
Following the storm a cold surge out of Canada spreads across the eastern two-thirds of the U.S. Later Christmas week another storm forms on the cold front and brings heavy rain to the Gulf region and possibly heavy snow to the southern Plains to Ohio Valley.
A stormy period for the Central U.S.
Pictured: U.S. temperature anomalies for the week of Dec. 24-30, 2017.