NY NJ PA Weather Forecasts

Evening Thoughts- storm threat increases for Friday

10:15 PM

Tonight I’ve been going over the various models from the 12Z and 18 Z guidance.  First I want to touch on the storm potential for Thursday night into Friday.

The 18Z models are a good indicator of where models are trending or adjusting to.  Both the 18Z GFS and NAM produced a stronger and more westward positioned coastal low for Thursday night into Friday for the northern Mid Atlantic.  By thoughts in the morning have not changed on the threat of this storm regardless of model guidance uncertainty due to the basic physical laws of meteorology that are governing the development of this coastal low.  The reason for my confidence that this storm will impact much of the Philadelphia and New York City metropolitan area is that development and intensification of the upper low at 500 MB.  As the upper low intensifies, the surface low will be pulled west, thus lead to a period of heavy precipitation and strong winds from late Thursday night into Friday.  The storm could move further east if the upper low is not as intense, and that is certainly a possibility.  However, the constant on all model guidance has been for the 500 MB upper low to intensify and lead to a very significant coastal storm for the northern Mid Atlantic and especially for New England.

As for frozen precipitation threats, the boundary layer temperatures are still a significant issue and will prevent accumulation for most locations.  However, given the strong cold air advection, I can’t rule out a mix of snow with the rain at times even at the immediate coast.  I still like the idea of a potential light accumulation at elevation above 1500 feet in eastern Pennsylvania and northern New Jersey.  I will likely lower the high temperatures for Friday based on the latest data but I would like to see the 00Z guidance as well before finalizing that action.  Temperatures in the 40’s for most almost the entire northern Mid Atlantic seems like a good place to start off.

I also want to touch on the latter portions of the forecast for early December via the 12Z ECMWF.  The latter portion of the ECMWF for December 1 through December 4 depicts a scenario where frozen precipitation may be a threat that will have to be monitored.  As I discussed in the morning, if this weekend’s storm explodes as I think, than a 50/50 low would be in place to force redevelopment towards the coast.  The ECMWF is attempting to display this potential while keeping the primary surface low over the Great Lakes initially on Tuesday morning.  The cold front begins to stall off the Mid Atlantic coast, and as a result becomes a focusing area for potential low pressure development.  By Friday, December 4th,  the ECMWF suggests a low pressure system is developing over the North Carolina coastal waters while a cold air mass continues to build into the northern Mid Atlantic.  This time period enters about the time when I suggested a storm is highly possible.  I think there is a significant threat of a coastal storm with frozen precipitation as a threat even for the coastal areas.  The details can not and should not be discussed at this time, however the pattern on the ECMWF and on the ensembles are favorable for just that type of an event.

Tags: 18z gfs, accumulation, Albany, Allentown, Atlantic City, atlantic city weather, atlantic ocean, Belmar, boundary layer, Bridgeport, cape may nj weather, Citi Field, Coastal Storm, coastal waters, cold air, cold front, Connecticut, craigles nyc, current weather in new york, eastern Pennsylvania, elevation, Freehold, hail, Hartford, heavy rain, High Temperatures, intensification, Islip, jackson nj weather, lightning, long beach island nj weather, Long Island, Long Island Sound, Long Island weather, manhattan weather, marine weather nj, meteorology, metropolitan area, Mets, Mid Atlantic, Mid Atlantic weather, Model Guidance, nam, New England, New Jersey, New Jersey coast, new jersey shore weather, New Jersey snowstorms, New Jersey Weather, New York, New York City, New York City Weather, New York snow storms, New York Weather, new york weather today, Newark, newark nj, newark nj weather, nj local weather, NJ Weather, nj weather 10 day forecast, nj weather forecast, nj weather radar map, nj weather report, northern Mid Atlantic, northern Mid Atlantic weather, ny weather 10 day, ny weather forecast, ny weather forecast 10 day, ny weather map, nyc weather map, ocean city, ocean city nj, pa weather alerts, pa weather forecast, pa weather map, pa weather radar, pa weather report, past new york weather reports, Pennsylvania, Pennsylvania weather, Philadelphia, philadelphia pa weather, Philadelphia Weather, Phillies, point pleasant nj, Poughkeepsie, precipitation, princeton nj weather news 12 nj weather, Reading, Scranton, scranton pa weather, seaside nj weather, snow, snow storms, strong, Strong Winds, Sussex, thoughts in the morning, thunderstorms, thursday night, tides, tornado, trenton nj weather forecast, uncertainty, weather and nyc, weather doylestown pa, weather easton pa, weather edison nj, weather for nyc, weather for pa, weather forecast pa, weather in new york, weather in nj, weather in nj today, weather in ny, weather in nyc, weather in nyc today, weather in pa, weather indiana pa, weather map, weather montclair nj, weather new brunswick nj, weather new york, weather new york city, weather newark nj, weather nyc, weather nyc forecast, weather nyc ny, weather ocean city nj, weather of nj, weather of nyc, weather princeton nj, weather scranton pa, weather union nj, weather wayne nj, White Plains, widlwood nj, Wild Wood, wild wood nj weather, Winter, winter 2009, winter forecast, winter predictions, winter weather 2009, winter weather advisory, winter weather forecast, winter weather predictions, yahoo weather nyc, Yankee Stadium, Yankees