1:00 PM (Monday) | *An interesting weather pattern setting up for the early part of December*
Paul Dorian
Significant anomalies of 500 millibar heights will be on the map later next week across North America with well above-normal heights centered in south-central Canada and well below-normal heights centered in the south-central US. Map courtesy NOAA, tropicaltidbits.com
Overview
The weather pattern will get pretty interesting next week to coincide with the beginning of the month of December and it will include some significant temperature and height anomalies across North America for this time of year. High pressure ridging in the upper part of the atmosphere will intensify dramatically next week across Canada at the same time colder-than-normal air sets up across the south-central US and there will be plenty of strong energy aloft. The transition to this possible colder and stormy weather pattern in the US (and warm weather pattern across Canada) could be preceded by a significant rain event in the eastern states as we end the month of November.
Warmer-than-normal air may be widespread across Canada next week while colder-than-normal air forms over the south-central US. Map courtesy NOAA, tropicaltidbits.com
Details
High pressure ridging will likely intensify significantly next week across Canada - possibly extending from coast-to-coast - and this type of upper air pattern potentially results in some interesting weather across the continental US during the winter season. Many computer model forecasts in recent days have been consistent in building strong high pressure across Canada next week virtually wrapping over the entire top of the US and colder-than-normal air will likely develop across the south-central states associated with deepening low pressure aloft. This colder-than-normal air may very well spread east into the eastern US later next week and there will be lots of energy to monitor moving west-to-east across the US - forced to move west-to-east across the US by the strong ridging extending all the way across Canada. While the US can become cold and stormy in this type of pattern in early December, it may become quite a bit warmer-than-normal across Canada. There is, however, a pretty extensive snow pack across Canada and this could limit the warm-up next week across the Canadian provinces.
The snow pack across the Northern Hemisphere has become pretty widespread in recent weeks with Canada and Russia mostly snow-covered as we approach the end of November. Map courtesy NOAA/NESDIS
The transition to a potential colder and stormy pattern in the US may very well be preceded by a significant rain event in the eastern states as we end the month of November. As a strong cold front drops south and east into the eastern states in the Sunday/Monday time period, low pressure may form in the frontal boundary zone and result in a significant rain event. After that initial storm, the overall pattern may very well remain on the stormy side given the blocking pattern that is likely to set up to the north of the US.
00Z Euro surface forecast map for early next week indicates the threat of significant rainfall in the eastern US as a cold air mass pushes to the south and east across the Great Lakes and towards the eastern seaboard. Map courtesy WSI, Inc, ECMWF
Stay tuned…the first couple of weeks of December could be pretty interesting.
Meteorologist Paul Dorian
Perspecta, Inc.
perspectaweather.com
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