Foggy start this morning with increasing flooding potential this weekend

8:00 AM

The temperatures may be warmer, but the active storm track that the Philadelphia and New York City metropolitan area experienced in February is returning once again.

The easterly fetch developing at the mid and lower levels of the atmosphere is already influencing the northern Mid Atlantic as Atlantic moisture moves into the coastal plain.  The combination of relatively light winds and high moisture levels has lead to the development of fog throughout the Philadelphia and New York City metropolitan areas and down through the New Jersey coast.  Visibility around 2 standard miles for most locations.

Overcast skies can be expected through the day along with a few widely scattered showers as weak disturbances move through the region from the southwest at 700 MB.  A warm front will begin to develop off the New Jersey coast tonight, enhancing an easterly wind and supporting increased isentropic lifting throughout the coastal plain.  As a result, scattered showers will begin to develop and increase in coverage through tonight and through the day tomorrow.

Meanwhile, the strong upper low currently over the central Plains will move east-southeast towards the Mississippi Valley by tomorrow morning and towards the Tennessee Valley by tomorrow night.  An area of low pressure will slowly develop over the Southeast, likely around South Carolina, and slowly move north and then northwest towards the Ohio Valley.  As this occurs, an occluded front will develop over the Tennessee Valley and move northeast towards the Philadelphia metropolitan area on Friday night.

Now, the development of this storm is rather complicated as there are several moving parts with this storm.  However, the overall result is pretty simple.  Due to the east based negative NAO pattern in the Atlantic, high pressure over Quebec is going to be locked into place through Saturday morning.  The position of this high pressure system will produce a cold air damning signature over the region, only that there will be no cold Polar air but rather an Atlantic maritime air mass.  This air mass is build over the northern Mid Atlantic while a warm front is stalled off the coast, which will lead to strong isentropic lifting this evening through Saturday morning and thus the threat of scattered showers.

The CAD will also lend support to the occluded front forming over the Tennessee Valley, which will lead to a “triple point” along the Virginia coast on Friday night.  It is this triple point or the place where the occluded, cold, and warm fronts meet; that a new coastal low will develop and move towards the New Jersey coast.  As the low intensifies down to a 998 to 1000 MB low, the pressure gradient between the strong Maritime high over Quebec and the surface low will increase and thus lead to strong winds throughout the region ranging from 20 to 35 mph with higher gusts along the coast and 15 to 30 mph with higher gusts over the interior.  The intense vertical and horizontal thermal gradient over the region will also lead to strong lifting or rising motion over much of the coastal plain and to a less extent over the interior producing very heavy rainfall from Saturday afternoon through Sunday morning.

The upper low responsible for the development of this storm will capture the low pressure system on Saturday night and cause the storm to stall over the region through the day on Sunday and into Monday morning.  The low pressure system will become vertically stacked due to the upper low capturing the surface low, which will cause the low to weaken rapidly but will keep the threat of showers in the forecast until at least Monday evening with an isolated threat on Tuesday morning.

This storm will be capable of producing 2 to as much as 4 inches of rain throughout the region which will likely lead to flash flooding of rivers, streams, and urban locations.  There will also be a minor to moderate threat of coastal flooding for the New Jersey coast, New York Harbor, and the north shore of Long Island through at least Sunday morning before winds start to back to the northwest through the day on Sunday.  Minor wind damage and significantly reduced visibility will also be an issue on Saturday.

The good news is high pressure will build into the region on Tuesday afternoon with clearing skies.  The latest models all suggest high pressure will remain in control of the Mid Atlantic with near to slightly above normal temperatures through the end of next week and into next weekend.

Tags: Albany, Allentown, Atlantic City, atlantic city weather, atlantic ocean, Belmar, Bridgeport, cape may nj weather, central Plains, Citi Field, coastal plain, coastal waters, cold air, cold front, Connecticut, craigles nyc, current weather in new york, east southeast, easterly wind, Freehold, hail, Hartford, heavy rain, Islip, jackson nj weather, levels of the atmosphere, light winds, lightning, long beach island nj weather, Long Island, Long Island Sound, Long Island weather, manhattan weather, marine weather nj, metropolitan area, metropolitan areas, Mets, Mid Atlantic weather, Mississippi Valley, moisture levels, moisture moves, move northeast, moving parts, 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, overcast skies, 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, princeton nj weather news 12 nj weather, Reading, saturday morning, scattered showers, Scranton, scranton pa weather, seaside nj weather, snow, snow storms, storm track, strong, Sussex, Tennessee Valley, thunderstorms, tides, tomorrow morning, tornado, trenton nj weather forecast, 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