Technical Discussion (Monday Afternoon Shift)

Synopsis:

 

The high pressure system that has controlled the region over the past few days is going to get the crap kicked out of it by a huge low pressure system gaining strength over the central plains. The combination of PVA, being on the eastern side of a large 500mb trough, and being the left exit region of a Jet Streak will strengthen this storm system that after tapping into the Gulf of Mexico's moisture will have enough energy to cause widespread flooding across the Allegheny Plateau. Behind this system it gets really dry and the coldest air of the season will move in for the weekend.

 

Short Term: Tonight

 

Increasing cloudiness from west to east as this storm approaches. Winds will also begin to pick up. Also I expect rain to begin falling in the westernmost portions of the state by daybreak.

 

Mid Term: Tuesday and Wednesday

 

This storm will track along the Allegheny Mountains causing the heaviest of rain to fall the central mountains of Pennsylvania. The rain will come in two waves; the first, which is associated with the warm front, will move through the state Tuesday morning and bring scattered showers to the western half of the state. The HRRR doesn't appear to have too much energy associated with this front so the rain will probably be quite scattered tomorrow morning. However, in the afternoon the second wave that is associated with the cold front will begin to move through the state. The cold front will also cause very gusty winds with some areas seeing gusts over 40 mph. Behind the cold front, the rain will end and move out of the region. I expect most of the heavy rain to be over by Thursday morning however, the damage will have been done with most of the state seeing anywhere between 2 and 3 inches of rain with locally heavier amounts possible.

 

Long Term: End of week

 

Behind this system, a northwestern flow will cause lake effect snow showers, predominantly on Thursday. Accumulations are expected to be minimal however; the extreme Northwestern part of the state could pick up a few inches. The lake effect will diminish on Friday as this storm system slides off to sea. A polar high pressure system will develop behind this storm causing the coldest weather yet this fall with some portions of the states reaching into the upper teens Friday or Saturday night.

RJ Patrizio