NY NJ PA Weather Forecasts

Heavy rain returns to forecast area

Latest Updates at the bottom!

2:59:00 PM: The heavy rain associated with the warm front is moving 4 to 6 hours faster than expected.

3:00:03 PM: Although the progression of the rain to the east is slow, rain has already started in eastern Pennsylvania.

3:01:07 PM: Expect the band of heavy rain to move over the entire forecast area this evening and overnight.

3:02:11 PM: Periods of heavy rainfall can be expected with decreasing visibility.
7:30:20 PM: The first wave of rainfall never reached the ground due to very dry air at the mid levels.

7:30:45 PM: However the atmosphere is now saturated and another wave of rainfall is on the way.

7:31:14 PM: Currently, light to moderate rain is approaching Philadelphia and over northeastern PA and Sussex, NJ.

7:32:09 PM: This rainfall will continue to the east and will impact the entire forecast area over the next 3 hours.

7:36:26 PM: A very impressive clash of air masses are taking hold. Take a look at the surface map! ttp://www.meteo.psu.edu/~gadomski/SFCNE/sfcloop.html

7:37:47 PM: High pressure remains just to the east of Long Island, while low pressure has slowly moved into Ohio.

7:39:24 PM: The position of the high pressure and low pressure is producing a strong pressure gradient over the region leading to E winds at 10-20 mph.

7:41:46 PM: The strong thunderstorms and heavy rain over western PA will impact the forecast area by early tomorrow morning with very heavy rainfall.

7:42:24 PM: Note that W PA is in the “warm sector” of the low pressure system where the atmosphere has become very unstable.

7:43:23 PM: Meanwhile, there is some indication of the low level jet stream at 850 MB developing as weak showers have started to develop and move north.

7:44:56 PM: The strengthening of the LLJ will be important, as the showers over C and E PA fill in, which can lead to widespread rainfall.

7:50:19 PM: http://www.meteo.psu.edu/~gadomski/SFCNE/zoom8.html

7:53:17 PM: Thursday appears to be setting up to be more of a wet day than severe day for the forecast area, especially along the coast.

7:53:54 PM: The latest guidance suggest that the 500 and 700 MB trough axis will be just west of the region and tilting negative.

7:54:42 PM: The position of the trough axis will produce a SE wind from 850 to 500 MB, that will bring plenty of moisture into the forecast area.

7:55:11 PM: Meanwhile, strong lifting at 500 MB will enhance lifting throughout the forecast area.

9:00:19 PM: Moderate to heavy rain is falling over eastern PA and western NJ and continues to move eastward.

9:01:59 PM: An area of heavy rain is developing over W PA and will continue to spread south and east through the overnight hours.

9:02:35 PM: Periods of heavy rain can be expected tomorrow morning throughout the Philadelphia and New York city metro.

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