An extremely cold plunge of Arctic air is forecast over the Christmas period for the far north of the U.S with temperatures hitting a bitterly cold 20’F below average. Temperatures widely of MINUS 24C (-11F) are forecast over Christmas day and Boxing day (26th December) for the far north, especially Minnesota, Wisconsin and Michigan and the upper mid west by the 26th with the severe freeze lasting up to or over a week in places places with heavy lake effect snow in the forecast. For example in Chicago, day time highs of 17F are expected by the 26th.
Winter 2017-2018 By Location U.S Forecast
The extreme cold will set in proper on Christmas day. Day time highs of 15-20F will be very widespread across the upper mid west, with Wisconsin, Michigan, North Dakota and Minnesota set to experience “dangerous – life threatening” cold on Christmas day. Temperatures of -22F at 5,000ft will relate to surface temperatures of around -5F as an average throughout the 48 hour period between Xmas day and the 26th, which is needless to say dangerous cold, at this time lake effect snow showers are forecast for the great lakes, especially on the east coasts.
The first swathe of Arctic cold will spread across the lakes and just flirt with, not completely hit the east coast over the Christmas period. Severe, heavy lake effect snow will fire up on the 26th and last through the 27th, burying many areas east of the main great lakes in over 12″ of snow through this period, however most areas especially NW New York state, Michigan, southern Ontario with the lake effect machine pasting areas near and around Toronto and near the border with the U.S in southern Ontario with 2-9″ of fresh snow. The brutal cold is expected to spread eastwards into the north east and east coast with further winter storms with heavy fresh accumulation likely in the week between Christmas and new year.