Thursday, September 17, 2015

Winter Coastal Storm Threat Enhanced From Warm Atlantic Waters

It does appear that the threat for significant East Coast winter storms is on the rise, as we have seen rapid and significant warming of the Atlantic waters along the coastline in the last few weeks.

ESRL
The above image shows daily sea surface temperature anomalies for September 15th. While there are a number of variables we could analyze in depth, I want to focus on the situation unfolding in the central Atlantic today.

Take note of strong positive SST anomalies from the East Coast through Nova Scotia, partially reaching into the open waters of the Atlantic before being stopped by a swath of below-normal SST anomalies west of Europe. These well-above-normal water temperatures could be a focal point for the coming winter.

Coastal storms that develop along the East Coast can turn into Nor'easters, infamous for dropping massive amounts of snow on inland Northeast communities, and sometimes large rain amounts along the coast. If we are to see this warmer than normal body of water maintain itself along the East Coast, both in position and strength, it's quite likely we will see an enhancement of any coastal storms that do develop along the East US. This would occur as the warm waters feed additional moisture and energy into the storm system, increasing precipitation and strengthening the storm system.

To Summarize:

- Warmer than normal water temperatures off the East Coast may increase the threat for stronger coastal winter storms in the coming cold season.

Andrew