Published June 18, 2026 6:23 AM EDT PHILADELPHIA - Warmer and more humid weather is moving in with temperatures expected to reach the 90s, but a cold front will bring relief and prevent a heat wave. Timeline: Scattered showers moved through the area this morning, with thunderstorms developing along the Pennsylvania and Maryland border and heading eastward. Some showers may reach Lancaster County, Wilmington, Delaware, and down the shore. Later today, a few pop-up storms are possible.