Excessive Heat Warning in Effect for Tuesday

An excessive heat warning is in effect until 7 p.m. Tuesday for Tredyffrin and Easttown townships as well as all of Chester County and most of Southeastern Pennsylvania.

The National Weather Service (NWS) issued the warning, predicting temperatures will soar to 90 for the return to work and school after the long Memorial Day weekend.

The NWS warning says "the first hot spell of this season will peak (Tuesday) afternoon."

The warning from the National Weather Service cautions:

AN EXCESSIVE HEAT WARNING MEANS THAT A PROLONGED PERIOD OF DANGEROUSLY HOT TEMPERATURES WILL OCCUR. THE COMBINATION OF HOT TEMPERATURES AND HIGH HUMIDITY WILL CREATE A DANGEROUS SITUATION IN WHICH HEAT ILLNESSES ARE LIKELY. DRINK PLENTY OF FLUIDS...STAY IN AN AIR-CONDITIONED ROOM...STAY OUT OF THE SUN...AND CHECK UP ON RELATIVES AND NEIGHBORS.

The first really hot spell of the year is expected to break later in the week.

The NWS Forecast through Thursday

Today: A chance of showers and thunderstorms, mainly after 3pm. Mostly sunny, with a high near 88. Southwest wind between 5 and 11 mph. Chance of precipitation is 30%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.

Tonight: Showers and thunderstorms likely, mainly before 1am. Mostly cloudy, with a low around 69. West wind between 5 and 9 mph. Chance of precipitation is 60%. New rainfall amounts between a half and three quarters of an inch possible.

Wednesday: A chance of showers and thunderstorms before 10am, then a slight chance of showers between 10am and 11am. Mostly cloudy, then gradually becoming sunny, with a high near 85. North wind at 6 mph becoming southwest. Chance of precipitation is 30%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.

Wednesday Night: A slight chance of showers before 2am. Partly cloudy, with a low around 59. South wind around 5 mph becoming calm. Chance of precipitation is 20%.

Thursday: Sunny, with a high near 77. North wind between 11 and 14 mph.

Thursday Night: Mostly clear, with a low around 52.