Strong Nor’easter to Develop Friday

A strong Nor’easter is expected to develop from a center of low pressure that will move from the Midwest over the Mid Atlantic coast Thursday night. Strong winds and heavy precipitation will likely create power outages and hazardous travel on Friday.

NAM Radar Friday March 2 2018 Noon
NAM 3km computer model display of potential weather conditions at noon on Friday. (image from tropicaltidbits.com)

While it is certain that a Nor’easter will strengthen rapidly over the Mid Atlantic coast, the type of precipitation received in the NYC Metropolitan Area will depend on its proximity to the coast. As of this afternoon, the ECMWF (European) and the NAM (North American) computer models are forecasting enough cold air to transition the heavy precipitation into snow by 10 am or noon Friday. Snow totals in locations where the precipitation does change over to snow could see snow totals exceeding half a foot to over a foot of snow by Saturday morning.

Snow Accumulation 18-2
Weather 360 72 Hour Snow Total Forecast Graphic as of 4:00 PM ET 2/28/2018.

 

Rounds of Storms Firing Up in NYC Metro Area

Thought it was over? Well, guess again…

Over the past hour and a half, a line of thunderstorms brought periods of heavy rain, gusty winds, and lightning to mostly northern portions of the Tri-State Area.  Although this line of storms may have cooled things down a bit, there is yet another, larger line of thunderstorms that has the potential to bring even more severe weather to the Metro Area later on in the evening.  With respect to the first line of storms, although they may not have gotten their act quite together when it comes to supercell development, they still packed a punch able to take down large branches, leaves, and lower visibility to less than a mile in some locations temporarily.

The line of storms that is expected to move into the Metro Area tonight will have even more ingredients necessary for Severe Weather Development in their favor.  After the first line of storms earlier, the Mixed Layered CAPE, instead of dropping off, skyrocketed from 700-1,100 joules per kilogram, to 1,500-2,000 joules per kilogram.  Along with this, there has been a notable increase in Effective Helicity as well as Effective Shear, indicating that stronger and more developed storms are on the way.

The most important thing to remember today is that the storms are not over, and that it will be important to have access to NOAA Weather Alerts via an NOAA Weather Alerts Radio or via Cellular Phone so you can stay informed if Severe Weather hits.