* WHAT...Heat index values up to 98 degrees expected.

* WHERE...In Delaware, New Castle County. In New Jersey, Mercer,
Camden, Gloucester, and Northwestern Burlington Counties. In
Pennsylvania, Delaware, Eastern Chester, Eastern Montgomery, Lower
Bucks, and Philadelphia Counties.

* WHEN...Until 8 PM EDT Wednesday.

* IMPACTS...Hot temperatures and high humidity may cause heat
illnesses.

* ADDITIONAL DETAILS...Record setting high temperatures are quite
possible through Wednesday, with maximum heat indices nearing 100
degrees during peak heating each afternoon. Given the intensity of
this early season stretch of heat and humidity, we are not
acclimated to it yet and therefore impacts could be greater if
precautions are not taken. Showers and some thunderstorms arrive
later Wednesday afternoon and evening which will break this early
season heat.

WWUS71 KPHI 190726
NPWPHI

Heat Advisory
National Weather Service Mount Holly NJ
326 AM EDT Tue May 19 2026
DEZ001-NJZ015-017>019-PAZ070-071-102-104-106
/O.CON.KPHI.HT.Y.0001.000000T0000Z-260521T0000Z/
New Castle-Mercer-Gloucester-Camden-Northwestern Burlington-Delaware-Philadelphia-Eastern Chester-Eastern Montgomery-Lower Bucks

...HEAT ADVISORY REMAINS IN EFFECT UNTIL 8 PM EDT WEDNESDAY...

* WHAT...Heat index values up to 98 degrees expected.

* WHERE...In Delaware, New Castle County. In New Jersey, Mercer,
Camden, Gloucester, and Northwestern Burlington Counties. In
Pennsylvania, Delaware, Eastern Chester, Eastern Montgomery, Lower
Bucks, and Philadelphia Counties.

* WHEN...Until 8 PM EDT Wednesday.

* IMPACTS...Hot temperatures and high humidity may cause heat
illnesses.

* ADDITIONAL DETAILS...Record setting high temperatures are quite
possible through Wednesday, with maximum heat indices nearing 100
degrees during peak heating each afternoon. Given the intensity of
this early season stretch of heat and humidity, we are not
acclimated to it yet and therefore impacts could be greater if
precautions are not taken. Showers and some thunderstorms arrive
later Wednesday afternoon and evening which will break this early
season heat.
Drink plenty of fluids, stay in an air-conditioned room, stay out of
the sun, and check up on relatives and neighbors.

HEAT ADVISORY

Heat Advisory issued May 19 at 3:26AM EDT until May 20 at 8:00PM EDT by NWS Mount Holly NJ

new castle

The Pennsylvania Department of Environmental Protection has issued a
Code Orange Air Quality Action Day for Ground Level Ozone, until
midnight EDT tonight.

An Air Quality Action Day means that air quality within the region
may approach or exceed unhealthy standards. For more information on
current and forecast concentrations of ground-level ozone and fine
particulates, visit www.airnow.gov or www.aqpartners.state.pa.us

AEUS71 KPHI 181358
AQAPHI

Air Quality Alert
National Weather Service Mount Holly NJ
958 AM EDT Mon May 18 2026
PAZ060>062-070-071-101>106
Berks-Lehigh-Northampton-Delaware-Philadelphia-Western Chester-Eastern Chester-Western Montgomery-Eastern Montgomery-Upper Bucks-Lower Bucks

...AIR QUALITY ALERT IN EFFECT UNTIL MIDNIGHT EDT TONIGHT...

The Pennsylvania Department of Environmental Protection has issued a
Code Orange Air Quality Action Day for Ground Level Ozone, until
midnight EDT tonight.

An Air Quality Action Day means that air quality within the region
may approach or exceed unhealthy standards. For more information on
current and forecast concentrations of ground-level ozone and fine
particulates, visit www.airnow.gov or www.aqpartners.state.pa.us

Local Weather

Philadelphia, Pennsylvania, US