Fall officially began on Saturday morning at 10:49 AM. Our normal high for this time of year is 75 degrees and our normal low is 58 degrees. We will be pretty close to these temperatures during most of the week, but Wednesday will feel more summer-like as temperatures climb to about 7 degrees above normal.
Today, September 24th, will be a sunny and pleasant start to the week, although it will likely end up the coolest day of the week. The weather today is courtesy of a big bubble of high pressure over much of the east coast. We should manage to reach the low 70s for a high temperature by the end of the afternoon.
High pressure will push southward on Tuesday, September 25th, and give way to an approaching cold front from the west. We'll still enjoy bright sunshine to start the day, but by the mid to late afternoon hours you will notice a few more clouds starting to build into the region. Expect a high temperature of 75.
The cold front will move through the region on Wednesday, September 26th, so look for spotty showers and thunderstorms throughout the day. However, before the front moves to the east of the Delaware Valley, a surge of warm air should push temperatures into the low 80s.
Behind the cold front, Thursday, September 27th, will be nearly 10 degrees cooler than Wednesday. Morning clouds will give way to increasing sun. The high temperature will be in the low 70s.
High pressure will be in control for most of Friday, September 28th, but an approaching low pressure system will increase the clouds and lead to a possibility of showers Friday night. The high temperature will be in the mid 70s.
Low pressure will park itself over Pennsylvania on Saturday, September 29th, throwing scattered showers into the Delaware Valley. At this point, I don't think the day will be a wash-out, but keep track of the forecast throughout the week for any changes that may occur. Despite plenty of clouds, we should manage to reach a high of 75.
Low pressure will move to our south by Sunday, September 30th, but a leftover shower is still possible. Otherwise, look for a mix of sun and clouds and a high in the low 70s.
Enjoy the first week of fall and be sure to check in with Phillyweather.net throughout the week!