Tuesday, November 22, 2011

Models Hinting at Nov. 30 Storm; Teleconnections Offer Glimmer of Hope

ECMWF Projected Low Placement on November 29 (circled in blue)

Projected November 30 temperature Anomalies

Projected November 30 Snow Depth
The GFS and ECMWF models are hinting at a storm system over the Midwest/Ohio Valley in the very late November time frame. The GFS believes areas within the two aforementioned regions could receive some light snow, while the ECMWF takes the low farther north into Illinois where some snow would likely be found in Wisconsin. Temperature anomalies are suggesting the potential for a major cool down in the Southeast US into the Midwest and Plains, with temperature anomalies as low as under 10 degrees below normal.
The teleconnections are less impressed by this prospect. They are offering a small chance for some snow and cold chances, particularly in or just after the November 30th timeframe. Today's 12z ECMWF has indicated that the PNA index, so stubbornly negative for a long time now, thus preventing cold and snow, may turn positive for a couple days while this storm makes its way across the Ohio Valley and Midwest. However, the ECMWF also keeps the NAO, WPO and AO indices positive, which are bad signs for snow lovers. All in all, it's up to the teleconnections. Models are very prone to have trouble in the long range, so don't take this as gospel.

On a side note, the Accuweather Updated Winter Forecast will be released December 1st. From what i've heard, some changes (possibly bad for snow lovers) are in the works. I stand firm by my forecast and believe any changes that may be made that would result in a shortened or less-harsh winter for the Midwest is incorrect. 

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