Thursday was a gorgeous day with a hint of September wrapped up into it! The day was filled with sunshine and then those fair weather cumulus clouds once we reached our convective temperature(the estimated temperature that the surface must warm to in order for clouds to develop). After a morning low of 62 at Philly International Airport we reached a high of 79 twelve hours later at the stroke of 4. There were some isolated showers and thunderstorms that pushed in around 8pm and dropped 0.25" within an hour, but they had pushed eastward. This means that overnight will be mostly clear and cool as lows will dip down to the upper 50s(the average low should be around 68).
High pressure is still in control of our weather, but the upper level low parked atop Southern Canada is still spinning around; this means that Friday will be just like Thursday with sunshine and those fair weather cumulus clouds bubbling up in the afternoon. There could be an isolated shower or thunderstorm, but primarily that will be to the north. Highs will be in the upper 70s(which is 5-8 degrees below average) with a westerly wind between 10-15mph.
Come Saturday we're still below average with highs around 80 as there will be sunshine and then high clouds moving in by the afternoon due to a cold front that will be diving southward from the Great Lakes; overnight lows will be in the upper 60s with an overcast sky while Sunday morning will feature showers and thunderstorms with highs in the middle 80s. We'll clear out by the evening with lows in the middle 60s while Monday will be in the lower 80s with sunshine and a northerly wind.
Come Tuesday that frontal boundary to our south will try and progress northward as a warm front; highs will be in the lower to middle 80s with sunshine giving way to clouds in the afternoon ahead of the front. Overnight will be in the upper 60s with scattered showers and thunderstorms as the warm front pushes through; this means Wednesday will be warm and humid with highs in the upper 80s with morning clouds giving way to sunshine in the afternoon. A cold front will be approaching from the west on Thursday, but ahead of it will be hot and humid with highs in the lower 90s.
So summer makes a return as the season comes to an end in less than three weeks(well, meteorologically);
don't forget that you can check out the 7-day forecast(as well as obtain radar and satellite maps) any time at www.scottderekwx.com/forecast.html.