Saturday, November 7, 2009

The perfect storm on the 12z GFS

Not going to happen, but I want to tell you about the 12z GFS forecast for midweek. It is quite interesting.

A mid level short wave trough over the Great Lakes digs south on Tuesday, and closes off over Pennsylvania Wednesday morning. At the surface, low pressure develops off the New Jersey coast and deepens rapidly on Wednesday. Moisture from the remnants of Ida gets pulled northward into the system. It is raining steadily over all of southern and central New England by Wednesday afternoon. As mid level heights continue to crash with the deepening storm, the column cools signficantly, allowing for a change to heavy snow. The storm is cut off from the flow, and sits east of Cape Cod through Thursday morning. In summary, the regions gets over 12 hours straight of blinding heavy snows with winds exceeding hurricane force!!! The GFS advertises QPF of 3" to 4" over central New England through Thursday.

Anyway, this one will be filed away in the folder marked "Twilight Zone Forecasts." In the mean time, the rest of the globals in addition to the GFS ensembles are much less supportive of Armageddon this week. They keep the shortwave over the Great Lakes more progressive and lower amplitude.

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