Tuesday Night Technical Discussion

Synopsis:

 

In the wake of a high pressure moving off shore, a southerly flow is advecting warmer and moist air into the region. The unseasonably warm and humid air will remain until Thursday when a cold front will make its way across the state, bringing widespread rain showers. Cooler air will follow the passage of the cold front for the end of the week into the weekend.

 

Short Term: (Tuesday Night through Wednesday Night)

 

The southerly flow associated with the Bermuda high off shore will continue to bring warm and humid air into the region until Thursday. There will potentially be warmer temperatures nearing 90 degrees in many locations after a mild night Tuesday night compared to Monday night, as well as a chance for widespread scattered showers and storms tomorrow afternoon during max heating.

 

Long Term: (Thursday into the Weekend)

 

Both 18Z GFS and NAM are agreeing with the cold front to move into northwestern PA by 12Z Thursday and exiting the Philadelphia area around 03Z Friday. The 21Z SREF also agrees with the timing of this front and all three models agree with significant rainfall and scattered storms accompanying the frontal passage. The 18Z 12km NAM has some scattered showers across northwestern and northern PA associated with the mean northerly flow off the lakes. Cooler and drier air will follow this front and bring temperatures to a seasonable value with highs averaging in the 60's, as high pressure will build over the region for the end of the week into the weekend.

 

~ A.J. Herbert