One of the most oppressive heat waves since mid July 1995 enveloped New Jersey from July 21st through the 24th. The heat was responsible for two deaths and hundreds of heat related injuries. Many locations had high temperatures that reached into the 100s. The most oppressive day was July 22nd when the combination of temperature and dew points pushed many afternoon heat index values to 110F to around 120F. While high temperatures on July 23rd were similar in the central and southern parts of the state, dew point temperatures and the heat index values were lower.
There were heat related deaths in Burlington and Mercer Counties. Both people were found indoors without air-conditioning. There were hundreds of cases heat exhaustion and other heat related illnesses. Health authorities were seeing younger people than typical. The largest concentration of heat related injuries occurred at the Vans Warped Tour stop at Monmouth Park in Oceanport (Monmouth County) on the 24th. Three hundred and one people were treated for heat exhaustion, twenty-seven were taken to hospitals, three were admitted. One child suffered heat exhaustion while participating in a rugby tournament in Morris County on the 23rd.

To combat the heat, many counties, cities and municipalities opened cooling centers. Nearly every county in the state opened cooling centers. New Jersey activated its 211 information line. The hours of air-conditioned senior citizen centers were extended.  People flocked to the malls, movie theaters and pools to keep cool. Construction workers adjusted their work days and started early. Paving work was postponed.  Water and electrical service shutoffs were postponed. Home air-conditioning repairs, ice suppliers, automobile air conditioning repairs, chilly treat vendors all saw increases in demand as was an increase in water deliveries. Ironically the excessive heat caused a drop in people going to the beaches as even there it was too hot and humid.
Utilities urged people to conserve electricity and water while many were setting usage records. Overall there were not many heat related power. The PJM Interconnect (manages high voltage transmission systems) which includes Pennsylvania, Delaware, Maryland and New Jersey set an all time record usage of 158,000 megawatts at 5 p.m. EDT on July 21st.  Atlantic City Electric set a new usage record of 3,074 megawatts at 3 p.m. EDT on the 22nd. Public Service Electric and Gas had its second highest electrical usage on record also on the 22nd only behind August 1, 2006.

The lack of rain along with the heat was stressing both farm crops (corn and soybeans in particular) and livestock
Highest temperatures (all of which occurred on either the 22nd or 23rd in the southeast part of the state) included 106 degrees at the Mercer County Airport in Trenton, 105 degrees at the Atlantic City International Airport and New Brusnwick (Middlesex County), 104 degrees in Somerville (Somerset County) and Chatham (Morris County), 103 degrees in Lakehurst (Ocean County), 102 degrees in Belmar (Monmouth County) and Sicklerville (Camden County), 101 degrees in Lumberton (Burlington County, Pequest (Warren County) and Andover (Sussex County) and 100 degrees in Millville (Cumberland County) and Wildwood (Cape May County).    The highest hourly heat index at the Atlantic City International Airport was 122 degrees on the 22nd.
At the Atlantic City International Airport, the 105 degree high temperature was the second hottest day on record and hottest since June 28, 1969 (106 degrees)  and the 4th highest maximum temperature on record. The minimum temperature of 84 degrees on the 23rd was the warmest or highest  minimum temperature on record.  The monthly average temperature of 81.0 degrees was not only the warmest July on record, but also the warmest month ever. The 20 days in which the maximum temperature reached 90 degrees or high is second only to 1983 with 21 days.
At the Mercer County Airport in Trenton, the monthly average temperature of 80.9 degrees was not only the warmest July on record, but also the warmest month ever. The 21 days in which the maximum temperature reached 90 degrees or high also established a new record.

This heat wave helped make July 2011 the third hottest July on record for the state of New Jersey with a statewide average temperature of 78.4 degrees.

A weak cold front ended the heat wave on the 25th.

Excessive Heat in SUSSEX, NEW JERSEY
From 21-JUL-11 09:00:00 to 24-JUL-11 19:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Excessive Heat in WARREN, NEW JERSEY
From 21-JUL-11 09:00:00 to 24-JUL-11 19:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Excessive Heat in HUNTERDON, NEW JERSEY
From 21-JUL-11 09:00:00 to 24-JUL-11 19:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Excessive Heat in MORRIS, NEW JERSEY
From 21-JUL-11 09:00:00 to 24-JUL-11 19:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Excessive Heat in SOMERSET, NEW JERSEY
From 21-JUL-11 09:00:00 to 24-JUL-11 19:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Excessive Heat in MIDDLESEX, NEW JERSEY
From 21-JUL-11 09:00:00 to 24-JUL-11 19:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Excessive Heat in WESTERN MONMOUTH, NEW JERSEY
From 21-JUL-11 09:00:00 to 24-JUL-11 19:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Excessive Heat in EASTERN MONMOUTH, NEW JERSEY
From 21-JUL-11 09:00:00 to 24-JUL-11 19:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Excessive Heat in EASTERN OCEAN, NEW JERSEY
From 21-JUL-11 09:00:00 to 24-JUL-11 19:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Excessive Heat in WESTERN OCEAN, NEW JERSEY
From 21-JUL-11 09:00:00 to 24-JUL-11 19:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Excessive Heat in CAMDEN, NEW JERSEY
From 21-JUL-11 09:00:00 to 24-JUL-11 19:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Excessive Heat in WESTERN ATLANTIC, NEW JERSEY
From 21-JUL-11 09:00:00 to 24-JUL-11 19:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Excessive Heat in EASTERN ATLANTIC, NEW JERSEY
From 21-JUL-11 09:00:00 to 24-JUL-11 19:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Excessive Heat in EASTERN CAPE MAY, NEW JERSEY
From 21-JUL-11 09:00:00 to 24-JUL-11 19:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Excessive Heat in WESTERN CAPE MAY, NEW JERSEY
From 21-JUL-11 09:00:00 to 24-JUL-11 19:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Excessive Heat in CUMBERLAND, NEW JERSEY
From 21-JUL-11 09:00:00 to 24-JUL-11 19:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Excessive Heat in GLOUCESTER, NEW JERSEY
From 21-JUL-11 09:00:00 to 24-JUL-11 19:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Excessive Heat in SALEM, NEW JERSEY
From 21-JUL-11 09:00:00 to 24-JUL-11 19:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Excessive Heat in MERCER, NEW JERSEY
From 21-JUL-11 09:00:00 to 24-JUL-11 19:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Excessive Heat in SOUTHEASTERN BURLINGTON, NEW JERSEY
From 21-JUL-11 09:00:00 to 24-JUL-11 19:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Excessive Heat in NORTHWESTERN BURLINGTON, NEW JERSEY
From 21-JUL-11 09:00:00 to 24-JUL-11 19:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS