Dry, Cool, and Comfortable Conditions Continue

5:15 AM

High pressure will continue to be the dominant influence on the region through the next three days.  The high pressure system is supported by weak convergence and confluence at 500 MB this afternoon.  This pattern is expected to remain in place through this week, which will keep the dry, cool air mass in place.

While the very enjoyable weather conditions continue over the forecast area, trouble is brewing off the East coast as a stationary front lingers over the coastal waters.  Several weak disturbances, like the one on Friday seen on the map to the right, will move over the coastal waters and spawn weak surface low pressure along the stationary front.  There is some model guidance that suggest precipitation may creep into the forecast area, however I think the very dry air that is established over the coastal plain will result in most of this precipitation ending up as virga on Friday evening.  Virga is precipitation that evaporates before reaching the ground.

The disturbance on Friday evening will be the only threat for precipitation for the rest of the forecast period.  High pressure over the Great Lakes will slide towards New England and build down through the Mid Atlantic.  Generally clear skies and low humidity can be expected through Memorial Day weekend along with temperatures averaging near normal, in the upper 70′s to lower 80′s.

One aspect of the forecast does present some uncertainty going forwards, which is the future of Tropical Storm Erika.  There is a variety of solutions being presented by the various model guidance this morning that range from Erika being a weak tropical system, barely relevant to the forecast to a strong major hurricane approaching the East coast.  The ECMWF this morning presents a very tricky set up with the upper level trough exiting the Northeast just in time for Erika to approach the East coast.  If the timing of the trough pans out on the ECMWF, then there would be no upper level mechanism to force Erika to turn north and northeast back into the northern Atlantic.  Of course, all of this speculation as is barely moving much any around the northern Leeward Islands.  However, it is clear that the future of Erika will have a role to play for the forecast area, the question is whether that role is simply choppy ocean conditions or something much more.

Tags: air mass, Albany, Allentown, Atlantic City, atlantic ocean, Belmar, Bridgeport, Citi Field, clear skies, coastal plain, coastal waters, confluence, Connecticut, cool air, dominant influence, ecmwf, forecast area, forecast period, Freehold, friday evening, hail, Hartford, heavy rain, Islip, level mechanism, lightning, Long Island, Long Island Sound, memorial day, Memorial Day Weekend, Mets, Model Guidance, New Jersey, New Jersey coast, New York, New York City, Newark, Pennsylvania, Philadelphia, Phillies, Poughkeepsie, Reading, Scranton, stationary front, Sussex, thunderstorms, tides, tornado, tropical system, upper level trough, virga, weather conditions, White Plains, Wild Wood, Yankee Stadium, Yankees