The overall probability of a white Christmas in the Upper Midwest. A white Christmas is defined as having at least 1" of snow on the ground around 7am local time Christmas morning.
The overall probability of a white Christmas across the U.S. A white Christmas is defined as having at least 1" of snow on the ground around 7am local time Christmas morning.
Snow depth across Minnesota on the afternoon of Thursday December 13th
The river of air at the top levels of the atmosphere called the jet streams are splitting across North America. The Polar jet surges into Canada, & taking the Arctic air w/ it. The subtropical jet coming into the southern US brings warmth & moisture.
The polar jet continues to show a ridge in central North America allowing relatively mild air surge northward... this keeps the Arctic air bottled up near the North Pole
While there are some shifts in the jet stream pattern by the end of next week, the link up of the polar jet and subtropical jet typically means a warmer pattern for much of the U.S. when they both surge northward into Canada like this