NOTE: This forecast was published in October 2011; see our full-length 2012-2013 AccuWeather.com Winter Forecast for the latest information.
Apart from the Southwest, people across the western United States can expect large swings in weather conditions throughout the winter, according to the AccuWeather.com Long-Range Forecasting Team.
December is likely to feature above-normal warmth across much of the entire West. However, from late December into January, the team expects a transition where cold fronts will drop farther south along the West Coast, reaching northern and central California. This transition should bring temperatures back near normal, away from the interior Southwest.
The famed "Pineapple Express," a phenomenon that occurs when a strong, persistent flow of tropical moisture sets up from the Hawaiian Islands to the West Coast of the U.S., could develop for a time this winter. This phenomenon often leads to excessive rain and incredible snow events.
"Last year, California was hit hard when the Pineapple Express set up from Dec. 17-22, producing massive flooding and 13 feet of snow in the Sierra," Pastelok explained. "The Pineapple Express could develop for a period this winter and take aim at northern and central California. That could lead to monster snowfall and heavy valley rain with the risk of flooding and mudslides."
Snowfall is forecast to average out near or slightly above normal in the northern and central Sierra this year, depending on where the Pineapple Express sets up.
Above-normal rain and snowfall are also possible in the northern Rockies in January and in areas farther south and west during February.
Seattle and Portland are forecast to have a fairly typical winter with precipitation averaging out near normal. However, it will be a wet start to the season and frigid end. Near- to slightly above-average snowfall is expected in the Cascades.
Cold air focused over the northern Plains, Midwest and Great Lakes throughout the winter will likely spread farther west into the northern Rockies in January and February, though the worst of the cold for this region will last from February into March.
A major Thanksgiving Day storm threatens to ruin holiday events across the Central states with flooding rain, snow, a glaze of ice and fog.
Sandra remains on track to target northern Mexico Friday and Saturday, but it should be much weaker at landfall than its current major hurricane status.
Unsettled weather will stretch across the United Kingdom on 27th November as millions set out in search of the best Black Friday deals on offer.
Travel hazards, delays and disruptions associated with rain, ice and snow will continue over the Central states through the balance of the Thanksgiving weekend.
Compared to Thanksgiving Day in 2014, this Thanksgiving will be substantially warmer in the Northeast.
Wet weather will stretch from Texas to Michigan and could impact shoppers and slow travel during Black Friday.
Thanksgiving Weekend blizzard begins. A total of 21.5 inches of snow in Denver (26th-27th). Zero visibility at Limen, Co, for 24 consecutive hours.
New England (1888)
Hurricane passed inside Nantucket over Cape Cod. Later crossed Nova Scotia Block Island- 84 mph wind gust.
North Dakota (1896)
Thanksgiving Day Blizzard. "Wind Velocity and snowfall never equalled before."