Weather Services International: Expect warm fall

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Weather Services International (WSI), a private forecasting company owned by the Weather Channel, is calling for a warmer than average fall for much of the mid-Atlantic and Northeast:

Predicted departure from normal for fall temperatures. Source: WSI.

"The combination of the La Nina event, a relatively cold north Pacific, and a record warm north Atlantic are quite bullish for a very warm fall period, especially across the northeastern quarter of the country," said WSI Chief Meteorologist Dr. Todd Crawford. "However, the historically persistent negative phase of the North Atlantic Oscillation, which would act to keep temperatures down in much of the eastern US, looms large as the most significant source of forecast uncertainty."

If this outlook is right, we may well add to our 90+ degree day tally -- currently at 54 and14 shy of the record set in 1980. La Nina years often produce warm falls. During our last La Nina fall in 2007, we had a streak of 3 straight 90+ degree days in early October and the month finished more than 8 degrees above average.

NOAA's Climate Prediction Center's outlook into the fall is in partial agreement with WSI, predicting above average warmth over the next 30 days, but equal chances of above and below normal temps through November.