This weekend's foray of summery temperatures and warmth is thankfully not a first fling into a long lasting heat wave. The combination of a weak backdoor cool front pushing down from New England and a ridge of high pressure in the atmosphere weakening a bit will help nudge temperatures back closer to reality for the start of the week. As the ridge of high pressure in the atmosphere continues to weaken, a cool front to our west will nudge east towards us for the middle portions of the week, bringing us a potential heavy rain and thunderstorm event for Tuesday night and Wednesday.
Computer model projections range anywhere from an inch of rain to perhaps over three inches of rain for the Tuesday night and Wednesday time frame, with higher rainfall totals possible over the Poconos. The combination of a moisture rich atmosphere, slow moving frontal boundary, and upper level wind trajectory will result in the possibility of thunderstorms popping up and tracking over the same area a few times in what is known is "training" -- not like those long webinars you love at the office, but similar to storms taking the same track multiple times like trains over tracks.
The brunt of the event is shaping up for Tuesday night and early Wednesday locally but with the front being slow to clear, the possibility of more showers and storms exists on Thursday as well thanks to lingering energy with the storm system. If we do pick up more than two inches of rain, localized flooding is a possibility along roads or in streams that are susceptible to minor flooding.
As of now, next weekend looks pretty good. There could be a few thunderstorms around Saturday afternoon but odds favor a generally decent weekend. Temperatures, which will dip to around 80 during the middle of the week for highs, will rebound and get back into the middle and upper 80's by Sunday. We could be back into the lower 90's early next week as high pressure builds just off shore and allows for warmth to bubble back into the region.
-------------------------------------------------------------------------------
Tom Thunstrom is the editor and publisher of Phillyweather.net. You can also follow Phillyweather.net on twitter@phillywx or on Facebook.