* WHAT...Heat index values up to 97 degrees expected. * WHERE...In New Jersey, Morris, Somerset, Warren, and Hunterdon Counties. In Pennsylvania, Berks, Lehigh, Northampton, Upper Bucks, Western Chester, and Western Montgomery Counties. * WHEN...Until 8 PM EDT this evening. * IMPACTS...Hot temperatures and high humidity may cause heat illnesses. * ADDITIONAL DETAILS...Record setting high temperatures are quite possible through today, with maximum heat indices of 95 to near 100 degrees during peak heating this 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 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.
The New Jersey Department of Environmental Protection has issued a Code Orange Air Quality Action Day for Ground Level Ozone, until 11 PM EDT this evening. An Air Quality Advisory 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.state.nj.us/dep/airmon/ or call the New Jersey Bureau of Air Monitoring at 609-292-0138
AI Weather Forecast · Tuesday, May 19, 2026
7 AM – 6 PM
Sunny. High near 98, with temperatures falling to around 95 in the afternoon. Heat index values as high as 98. Southwest wind 5 to 14 mph, with gusts as high as 25 mph.
6 PM – 6 AM
Partly cloudy, with a low around 75. Heat index values as high as 95. Southwest wind 5 to 13 mph, with gusts as high as 23 mph.