Daily temperatures naturally fluctuate from week-to week and year-to-year (factoring out the seasonal “march” of temperature). Thus when temperature trends emerge over decades, it sparks a special interest here in the Office of the New Jersey State Climatologist. We are in the midst of a project to examine prolonged heat episodes throughout the state and have found some evidence for recent increases in such events. As impressive winter cold slowly comes to an end in NJ is there a better time to present some of our heat results? Of course not!
Our study involves examining daily maximum and minimum temperatures for seven stations distributed across the state, each with 100-plus years of records. This study began last summer with an evaluation of New Brunswick heat events. We showed that New Brunswick has had an increase of daytime heat events in recent decades and nighttime heat events are becoming more commonplace. In the course of expanding our analysis to seven stations, we have found larger changes in warm nighttime temperatures than in hot daytime temperatures. Excessively warm nighttime temperatures typically get overlooked when discussing potentially dangerous heat episodes, yet they can bring about dangerous health concerns for those unable to escape persistent warmth.