Here we go, the warmup begins with highs in the mid-80s on Wednesday in the Philadelphia region. Shorts and T-shirts will be needed to stay comfortable as we move into the third day of the meteorological summer. NEXT big weather changes Expect our second heatwave of the season to begin on Thursday, with highs in the low 90s, and by Friday and Saturday, we'll be in the mid-90s. We're tracking our next rain chances for Sunday as a cold front approaches the area.