Technical Discussion

Synopsis...

A fairly complex forecast in store for the short term as a large swath of moisture moves it's way up the middle atlantic and southeastern United States.  A large gradient of precipitation amounts over the state of Pennsylvania results in difficult pinpointing of exact amounts but a general increase in precipitation as one goes east across the state is in order. Behind this system, wrap around moisture/lake effect rain or show showers will ensue for the western portions of the state, so anyone who didn't pick up rain from the initial system will likely get some on the back half of it.  Things clear out for the weekend with cooler and clear conditions, with the exception of near the lakes where lake effect could continue into late Saturday.

Short Term...

The rain at this hour is over much of Pennsylvania, with a very well-developed synoptic swath of rain moving up the eastern seaboard.  Places such as Allentown have already reported over a half of an inch of liquid precip as of this hour, and more is likely to fall over the next 6-12 hours. Thus, I think it prudent at this point to stick with the SREF precipitation distribution as it has done considerably well up to this point.  The ensembles show over an inch from Philadelphia to Allentown, decreasing to around .50" near State College and to less than .25" for the Pittsburgh region.  After the main synoptic precipitation moves through, the northwesterly flow behind the system will create lake enhanced precipitation into Saturday for northwest portions of the state.  Some areas near Meadville and Bradford could see a couple of inches of measurable precipitation, while near the lake shore this precipitation will most likely be in the form of rain.  Close to my home town down in the Laurel Highlands will get in on the snow action as an inch or two could even accumulate down in those regions as well, especially near Seven Springs.  Pinpointing this lake effect will be determined by the difference between the lake and air temperatures and whether that difference gets to the magic 13 degrees celsius difference..something for later shifts to look at.

Long Term...

After the lake effect winds down, north-northwesterly flow will continue into the late weekend/early next weekend with clear conditions and moderating temperatures. I'll keep this short as the main focus of the forecast was in the short term...enjoy that extra hour of sleep this weekend!

Forecaster: Kyle Imhoff