Thursday Evening Technical Discussion

Synopsis

The upper level trough currently over the eastern United States will begin to slowly lift to the north over the next couple of days. As a result, this will decrease the shower activity and bring more seasonable and brisk conditions. Early next week, another trough will develop over the eastern United States bring more unseasonably cool weather and a chance for a storm later in the week.

 

Short Term

 

 Currently, there are bands of showers that will continue to move to the north across Pennsylvania overnight. As we approach the morning hours on Friday, there is the chance of fog developing as there is lots of moisture in the air just above the ground. The main weather maker on Friday is the cold frontal passage that is progged to pass through the PA between about 10 am and 3pm. Behind this front, temperatures begin to fall as there is strong cold air advection from the west as well as gusty winds. Temperatures will fall to mid-40'a over most of commonwealth Friday night as the northwesterly flow continues.

 Mid Term

 On Saturday, the closed low over the great lakes will move into Canada. Both the 21z SREF and 00z NAM indicate the possibility of winds of 20-25 knots with gusts approaching 30 knots on Saturday. Drier air will also work into the area due to the strong northwesterly flow and substantially decrease the chances of showers over the commonwealth. This strong low will create quite a pressure gradient which will result in strong westerly winds again during the day on Saturday. Temperatures will rebound to near normal on Sunday. However, the winds will remain through Sunday and make it feel much colder.

 Long Term

 Winds will gradually slacken on Monday as the pressure gradient relaxes and allows temperatures to moderate. However, the trough over the southeast Canada will remain entrenched and gradually move back south into the central United States. This will keep us in a pattern with temperatures near average to just below. Mid-next week there is a chance that a low pressure system could form in the Ohio River Valley and track up across the forecast area Tuesday into Wednesday bringing a chance for precipitation.

-Matt Mehallow