Heat Index Expected to Soar Saturday

The National Weather Service has issued an excessive heat warning for the Malvern area and surrounding counties effective Friday, July 6, through Sunday morning, July 8.

An accompanying hazardous weather outlook describes a chance of severe thunderstorms late Saturday into Sunday, with "locally damaging wind and hail."

Here is the NWS forecast for Malvern:

• [Friday] Afternoon Sunny, with a high near 95. Northwest wind around 6 mph.
• [Friday night] Mostly clear, with a low around 74. Southwest wind around 6 mph becoming calm in the evening.
• Saturday Sunny and hot, with a high near 101. Heat index values as high as 105. Light west wind increasing to 5 to 10 mph in the morning.

Here is the full NWS warning, which applies to greater Philadelphia:

Excessive Heat Warning Now In Effect Until 6 a.m. Sunday:

* HEAT INDEX VALUES...UP TO 108 SATURDAY AFTERNOON DUE TO TEMPERATURES IN THE LOWER 100S...AND DEWPOINTS IN THE MID 60S. THE FORECAST HIGH TEMPERATURES FOR SATURDAY WILL BE NEAR THE RECORD OF 103 DEGREES SET ONLY TWO YEARS AT TRENTON...PHILADELPHIA AND WILMINGTON.

* WARNING EXTENSION...THIS WARNING HAS ALREADY BEEN EXTENDED THROUGH ALL OF SATURDAY NIGHT AS LOWS SUNDAY MORNING SHOULD ONLY BE 80 TO 85 DEGREES IN PHILADELPHIA! THEN DEPENDING ON THE ONSET OF THUNDERSTORMS SUNDAY...ITS POSSIBLE THE WARNING WILL HAVE TO BE EXTENDED INTO SUNDAY AFTERNOON. FOR NOW...SUNDAYS HIGH TEMPERATURES ARE PROJECTED TO BE IN THE MID 90S.

* RELIEF...LOWER DEWPOINTS HAVE PERMITTED SOME RELIEF TODAY BUT EVEN SO...THE TEMPERATURE THIS AFTERNOON WILL RISE INTO THE MID TO UPPER 90S. SUBSTANTIAL RELIEF WILL NOT ARRIVE UNTIL SUNDAY NIGHT OR MONDAY.

* IMPACTS...THE CUMULATIVE IMPACTS OF THE HEAT ARE A DANGER ESPECIALLY FOR THE ELDERLY... INFIRM... THE VERY YOUNG... AND THOSE IN INNER CITY AREAS THAT DO NOT HAVE AIR CONDITIONING. PETS ALSO ARE SUSCEPTIBLE TO THE HEAT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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.

PLEASE MAKE SURE THAT PETS HAVE ACCESS TO PLENTY OF COOL WATER AND A SHADED AND WELL VENTILATED AREA. THE MOST HUMANE THING TO DO IS TO BRING THEM INTO AN AIR CONDITIONED PLACE.

NEVER LEAVE ANY PERSON OR ANIMAL IN A PARKED VEHICLE FOR ANY LENGTH OF TIME.

TAKE EXTRA PRECAUTIONS IF YOU WORK OR SPEND TIME OUTSIDE. WHEN POSSIBLE...RESCHEDULE STRENUOUS ACTIVITY TO EARLY MORNING OR EVENING. KNOW THE SIGNS AND SYMPTOMS OF HEAT EXHAUSTION AND HEAT STROKE. WEAR LIGHT WEIGHT AND LOOSE FITTING CLOTHING WHEN POSSIBLE AND DRINK PLENTY OF WATER.

TO REDUCE RISK DURING OUTDOOR WORK...THE OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION RECOMMENDS SCHEDULING FREQUENT REST BREAKS IN SHADED OR AIR CONDITIONED ENVIRONMENTS. ANYONE OVERCOME BY HEAT SHOULD BE MOVED TO A COOL AND SHADED LOCATION. HEAT STROKE IS AN EMERGENCY - CALL 9 1 1.