Mercer County Heat Wave: All Cooling Center Locations & Hours

MERCER COUNTY, NJ — Mercer County has opened a network of cooling centers across its municipalities as an extreme heat warning remains in effect until 8 p.m. EDT Saturday, July 4, 2026.

The National Weather Service warned that "dangerously hot conditions with heat index values between 105 and 115 degrees" are expected each day through the warning period. The advisory covers portions of northern Delaware, central and southern New Jersey, and southeast Pennsylvania.

According to the National Weather Service, overnight lows in the mid-70s to low 80s "will not offer any relief from the heat," compounding the impact of consecutive days of near-record temperatures. The hottest conditions were expected from July 2 through July 3, 2026.

The National Weather Service cautioned that heat-related illnesses "increase significantly during extreme heat and high humidity events" and urged residents to drink plenty of fluids, stay in air-conditioned spaces, avoid direct sun, and check on relatives and neighbors. Officials also warned against leaving children and pets unattended in vehicles, noting car interiors can reach lethal temperatures within minutes.

Residents working outdoors were advised to take frequent breaks in shaded or air-conditioned areas and to limit strenuous activity to early morning or evening hours. Anyone showing symptoms of heat exhaustion or heat stroke should be moved to a cool, shaded location immediately; heat stroke is a medical emergency requiring a call to 911.

Residents without air conditioning or shelter can call 211 or visit their county or state health department website for help locating relief from the heat.

Mercer County Executive Dan Benson and the Board of County Commissioners — Chair Terrance Stokes, Vice Chair Cathleen M. Lewis, John A. Cimino, Samuel T. Frisby, Kristin L. McLaughlin, Nina D. Melker, and Lucylle R.S. Walter — announced the following cooling center locations by municipality:

East Windsor

• Mercer County Library – Hickory Corner Branch, 138 Hickory Corner Rd.: Monday–Thursday, 9:30 a.m.–8:30 p.m.; Friday–Saturday closed for the July 4th holiday

• Mercer County Library – Twin Rivers Branch, 267 Abbington Dr.: Monday–Thursday, 9:30 a.m.–8:30 p.m.; Friday–Saturday closed for the July 4th holiday

• East Windsor Police Department, 80 One Mile Road: Open 24/7 in the lobby

Ewing

• Mercer County Library – Ewing Branch, 61 Scotch Rd.: Monday–Thursday, 9:30 a.m.–8:30 p.m.; Friday–Saturday closed for the July 4th holiday

• Ewing Township Fire Department Training Room, 1666 Pennington Rd.: Open July 1–3, 2026, 8 a.m.–6 p.m.

Hamilton

• Hamilton Township Senior Center, 409 Cypress Lane: Monday–Wednesday, 8:30 a.m.–4 p.m.; Thursday, 8:30 a.m.–7 p.m.; closed Friday for the July 4th holiday

• Hamilton Township Public Library, 1 Justice Samuel Alito Jr. Way: Monday–Thursday, 9 a.m.–8:30 p.m.; Friday–Saturday closed for the July 4th holiday

Hightstown

• Mercer County Library – Hightstown Memorial Library Branch, 114 Franklin St.: Monday–Thursday, 9:30 a.m.–8:30 p.m.; Friday–Saturday closed for the July 4th holiday

Hopewell Township

• Mercer County Library – Hopewell Branch, 245 Pennington Titusville Rd.: Monday–Thursday, 9:30 a.m.–8:30 p.m.; Friday–Saturday closed for the July 4th holiday

• Hopewell Township Municipal Building, 201 Washington Crossing Pennington Rd.: Open July 2–4, 9 a.m.–4 p.m.

Lawrence

• Mercer County Library – Lawrence Headquarters Branch, 2751 Brunswick Pike: Monday–Thursday, 9:30 a.m.–8:30 p.m.; Friday–Saturday closed for the July 4th holiday

• Lawrence Township Police Department, 2211 Lawrence Road: Lobby open 24/7 during the heat wave

• Lawrence Township Senior Center, 30 East Darrah Lane: Open 8:30 a.m.–4:30 p.m. through June 30–July 2, 2026, with possible extension to July 3 if needed

Princeton

• Princeton Public Library, 65 Witherspoon St.: Monday–Thursday, 9 a.m.–8 p.m.; Friday, 9 a.m.–5 p.m.; closed Saturday for the July 4th holiday; Sunday, 12–5 p.m.

Robbinsville

• Mercer County Library – Robbinsville Branch, 42 Robbinsville Allentown Rd.: Monday–Thursday, 9:30 a.m.–8:30 p.m.; Friday–Saturday closed for the July 4th holiday

• Robbinsville Police Department, 2300 Route 33: Open 24/7

Trenton

• Trenton Rescue Mission, 98 Carroll St.: Open 24/7

• Jennye Stubblefield Senior Center, 301 Prospect St.: Open June 30–July 2, 2026, 8 a.m.–8 p.m.

West Windsor

• Mercer County Library – West Windsor Branch, 333 N. Post Rd., Princeton Junction: Monday–Thursday, 9:30 a.m.–8:30 p.m.; Friday–Saturday closed for the July 4th holiday

• West Windsor Police Department, 20 Municipal Dr.: Open 24/7

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