Technical Discussion

Synopsis...

Low pressure over Lake Superior will be the cause of unsettled weather over the region today and tomorrow.  Heavy rain expected tonight with snow showers behind the system tomorrow.  Some minor accumulations are possible.  Typical westerly/northwesterly flow lake effect regime will set-up Thurs-Fri.  Slightly better day possible on Saturday before pattern becomes active again next week.  Temperatures will remain below average throughout the period.

Short Term (Tue-Wed)...

Temperatures in 40s and 50s across the state this morning with rain in most places.  Winds becoming gusty (35kts in ERI) across the Commonwealth and will continue to do so throughout the day.  Deep trough at 500mb promoting PVA ahead of it will help enhance precipitation across the Commonwealth today.  One slug of precip currently making its way northeastward.  Slight dry slot behind it in eastern Ohio should allow a break in the rain later this afternoon.  This will not last long though as secondary low pressure forms off the eastern seaboard allowing, enhancing precip tonight across the state.  Narrow cold frontal rain band tomorrow morning could bring a rumble of thunder and gusty winds (40-60mph) mainly in eastern half of state as front pushes eastward.  Nonetheless, very heavy rain 1-2"+ expected by the time the storm moves out tomorrow.  Cold air will immediately rush in behind the system. High temperatures will occur near daybreak in western zones on Wed and no later than noon across the east.  Winds stay gusty behind the front and shift to the west with temperatures falling to freezing by evening.

Long Term (Wed Night-Sat)...

Typical northwest flow regime sets up for Thurs-Fri with better chance of lake effect of snow on Friday as winds go more northwesterly rather than WSW.  Temperatures in the 30s which will be well below average.  Less chance of snow for Saturday but the next shortwave is not far away and could bring a swath of light snow for Sunday night.  Next week promises to be active with the possibility of the first major storm of the season.

-ddpdtdt