Daily Archives: Friday, August 1, 2025 4:28 pm

Philadelphia Area Weather Forecasts

WEEKEND WEATHER FORECAST

#Philadelphia #weather #PAwx #PhillyWx

Beautiful… with Smoke

Posted Sunday 08/03/25 @ 9:54 AM — Another beautiful day expected today, but an increasing flow of smoke from Canadian wildfires will put an increasing layer of haze over us. Near ground smoke concentrations may reach levels that give the air a distinct wood fire smell; something that has occurred a few times since Friday.

By tonight into Monday morning, a smell of smoke should be apparent to sensitive noses—

12z HRRR smoke model forecast: vertically integrated smoke with smoke levels 8 m above ground. (Click on image for a larger view.)

Blocking high pressure should keep low pressure suppressed to our south through at least late Wednesday. The forecasts diverge at that point, with the GFS-AI and the ECMWF-AI models bringing clouds and rain up the coast by Thursday, while the conventional numerical prediction models (GFS, ECMWF, GDPS) keep it suppressed to our south. The German ICON model is somewhat closer to the AI models.

This will be a good test for the AI models.

Today’s 06z GFS Forecast for Wednesday night. The AI models are very different, bringing the low pressure system inland and up the coast by Wednesday night A good test for the AI models. (Click on image for a larger view.)

Originally Posted Fri 4:28 PM —Sprawling high pressure moves in for the weekend, as the heat and humidity is suppressed far to our south.

00z GDPS with “AI Spectral Nudging” forecast for Friday evening. Black-grey is cloud cover. Orange contour is the 576 thickness line (1000-500 mb thickness) The 576 line is a dividing line between tropical air and more pleasant temperatures and humidity A weak tropical system move out to our southeast. (Click on image for a larger view.)

Saturday Forecast

Sunny with light winds, becoming somewhat breezy after noontime.

NBM high temperatures: Blue Bell, PA 81 º Philadelphia, PA 82º
Low Uncertainty (based on standard deviation): ± 0.9º

Sunday Forecast

Sunny, less windy

NBM high temperatures: Blue Bell, PA 84º Philadelphia, PA 85º
Low Uncertainty High Confidence (based on standard deviation): ± 0.9º