Category Archives: Weather Forecasts

Philly Labor Day Weekend Weather Forecast

Last Updated

GFS Surface Forecast late Sunday
GFS Surface Forecast late Sunday

High pressure slowly moves off the coast.  A southeasterly flow of moisture on Saturday will herald the approach of a warm front  that moves through Saturday night.  Warm and very humid conditions return late Saturday night through Monday.

A southwesterly flow of moisture will cause showers late Sunday through most of Monday, but the shower activity will be scattered.

It will not be very wet this weekend, but clear blue skies will be in short supply– expect considerable cloudiness from late Saturday through most of Monday with warm and humid conditions.

A chance of a shower is possible any time from Sunday afternoon through Monday.

Saturday 8/30: Sunshine giving way  to increasing cloudiness during the day.  Becoming more humid. High 83

Sunday 8/31: Considerable cloudiness with some sun, increasing chance of showers during the late afternoon. Very humid. High 86

Monday 9/1 :  Considerable cloudiness, some sun, very warm and very humid. Chance of scattered showers.  High 88



Philly Weekend Weather Forecast

Last Updated

Building cumulonimbus with altostratus  late Thursday
Building cumulonimbus with altostratus
late Thursday

A blocking pattern is causing high pressure near Nova Scotia to maintain an easterly flow of moisture, resulting in considerable cloudiness, cool temperatures and an ongoing chance of showers on Saturday.

This high pressure system is expected to build down over us later on Saturday, allowing a more northerly flow of drier air.  Clearing skies late Saturday should remain with us through Sunday.

The NAM has a much greater chance of showers during the day on Saturday than the GFS, but it has a tendency to overstate precipitation lately. Neither model has done very well with this blocking pattern over the past week and I have lower confidence in this forecast, especially for Saturday.

Sat 8/23: Mostly cloudy, a chance of widely scattered showers but mostly dry. Brightening skies late in the afternoon. High 77.

Sun 8/24: Sunny and warmer. Some fair weather clouds develop in the afternoon. High 83.