Forecast Discussion:
Cooler and much drier on Thursday. Winds will decrease by afternoon and allow particle concentration to begin to rise but the daily average will be in the good range.

Extended Forecast:
Warmer on Friday with humidity rising steadily through the day. Particle concentrations will rise but remain in the good range. Strong southerly winds with temperatures rising further on Saturday. Air quality will be near the top of the good range. To follow air quality in PHL between forecasts: "aqforecast" at www.twitter.com -Ryan