NY NJ PA Weather Forecasts

Upper Low Weakens And A Very Warm Friday Is Expected

This period will see a rather extreme swing in weather conditions over the next 66 hours.

The upper low and coastal low that brought have rainfall to the forecast area overnight is beginning to weaken and lift to the north and east.  With significantly moist air trapped below 850 MB, a cloudy day can be expected.  However, the majority of the strong lifting with this coastal low has moved to the north and east of the forecast area, which has caused the rain shield to collaspe.  Scattered showers will remain a threat through the afternoon hours before clearing enters the region from the south and west.

High pressure from the Tennessee Valley will build into the forecast area ahead of a strong cold front on Friday.  This will lead to partly cloudy skies and very warm temperatures.  I wouldn’t be surprised to see a 70 or 71 degree high over southern New Jersey or southeastern Pennsylvania, although this will likely be an isolated situation.  

A strong cold front and the beginning of a significant pattern change will impact the forecast area on Saturday.  The strongest upper level dynamics will lift to the north and east of the forecast area, thus I am taking the severe thunderstorm potential out of the forecast.  However, the clash of these two air masses along with strong PVA should produce some strong thunderstorms capable of frequent lightning and heavy downpours on Saturday afternoon.  Temperatures will warm into the 60’s ahead of the cold front before crashing into the 40’s and 50’s immediately behind this cold front.  

The upper level pattern will shift from a ridge over the forecast area to a deep, negatively tilted trough, which will provide the set up for some interesting weather later in the week.