FOX44 - Burlington / Plattsburgh News, Weather & Sports11.8.11 Hurricane Season Isn't Over Just Yet- Local Impact with Sean?

11.8.11 Hurricane Season Isn't Over Just Yet- Local Impact with Sean?

Subtropical Storm Sean Forms in the Atlantic

The 18^th named storm of the 2011 Atlantic hurricane season, subtropical storm Sean, has formed midway between the Bahamas and Bermuda. Sean is called a "subtropical" system, meaning it carries both tropical and non-tropical characteristics. Sean's  most prominent tropical characteristic is the absence of fronts. Tropical systems are fueled by warm water, versus non-tropical systems which live on by large temperature gradients around it, known as fronts. Sean's main non-tropical feature is an upper level cold core (tropical systems are warm core). Sean was actually a storm that produced big snow and stormy weather in the US several days ago, and migrating toward the Atlantic where it continued to spin and burrow down a surface circulation where it is now feeding off of the warm ocean water in the Atlantic.

As of 4am Tuesday morning, Sean had a minimum central pressure of 1002mb (not too impressive), sustained winds of 45 mph, and it was nearly stationary, sitting and spinning at roughly 27.2N 69.4W (or about 445 miles southwest of Bermuda).

Sean is one to watch for our region as some of the remnant moisture and energy may transfer close enough to the New England shores to produce a narrow band of moderate to heavy rain. Sean's storm center itself is forecast to turn to the northeast and head back to the open waters of the Atlantic. However, many models suggest a new low pressure may develop on Thursday south and east of the New England coast, which would allow this subtropical moisture to feed into eastern Massachusetts, Rhode Island, western Maine, New Hampshire and perhaps into eastern Vermont as well. This could mean a period of moderate to heavy rain on Thursday night if this would hold true. Most models are in good agreement with this moisture feed.

Having said this, the impact that Sean could bring is nowhere near the magnitude of the remnants of Hurricane Irene. Sean may bring a period of heavy rain, but not enough to cause widespread impact, damage, and devastation as Irene did. They should be treated very differently.

At the same time, a cold front is expected to move into western New England by Thursday night. This may allow some of the leftover moisture to interact with cold enough air, where some precipitation may fall as snow. At this time, it doesn't appear the timing will be right for any big snow accumulation, but perhaps a light amount over portions of northern NY, and the higher terrain of Vermont and New Hampshire.