Severe Weather

What can you say about a month that began with a swarm of tornadoes, finished with flooding rain, and in between, featured record heat, wildfires, and increasing drought concerns? Best to say that it was an odd one! Fitting this theme, the statewide average temperature of 55.4° was 3.9° above the 1991–2020 normal. This ranks as the third warmest April on record (since 1895) only behind 2017 and 2010 for top honors. April was the fifth month of the past ten ranking in the top 10, joining July (#7), August (#1), January (#1), and February (#5). The first four months of 2023 come in as the warmest start of the year on record with an average of 44.4°. This exceeds the previous record of 44.2° in 2012, with seven of the 10 warmest January–April periods (1895–present) occurring since 2002. The average April maximum temperature across NJ was 67.4° (+4.7°, 3rd warmest) and the average minimum was 43.4° (+3.1°, 5th warmest). Northern counties averaged 53.5° in April (+3.6°, 5th warmest), southern counties 56.6° (+4.0, 2nd warmest), and the coastal zone 55.8° (+4.1°, 2nd warmest).

April precipitation averaged 5.84” across New Jersey. This was 2.14” above normal, ranking as the 10th wettest on record. It was the wettest April since 2007 and second wettest since 1983. All but scattered areas in the northwest received above-normal precipitation, the greatest amounts falling near the Atlantic and Delaware Bay coasts. Northern counties averaged 5.55” (+1.65”, 26th wettest), southern counties 6.04” (+2.49”, 7th wettest), and the coastal zone 5.94” (+2.39”, 10th wettest). It is important to note that these totals and those for individual stations in the next section, do not include heavy rain that fell after standard early morning observation times at CoCoRaHS and National Weather Service Cooperative stations on April 30th. These rains were reported in morning observations on May 1st, thus will be included in May totals.

Wow, what a month. July 2021 provided a never-ending cascade of weather events, including a tropical storm, a record-tying number of tornadoes, large hail, flash floods, hot days, chilly nights, smoke-filled skies, and on the last day of the month, perhaps the nicest day of the summer. The statewide average precipitation of 7.59” was 2.88” above the 1991–2020 normal and ranked 8th wettest of all Julys back to 1895. It was the wettest July since 1975 and second wettest in almost 50 years. The northern portion of the state averaged 8.16” which was 3.44” above normal. The south averaged 7.36” which was 2.62” above normal.

The average temperature of 75.8° was 0.4° above the 1991–2020 normal, but 1.9° above the 1895–2021 average. This ranked as the 24th warmest July since 1895. 13 of the 25 warmest Julys in the past 127 years have occurred since 2002. The nine July tornadoes is the most in a month since official records began in 1950. Tropical Storm Elsa was the earliest fifth storm of any season on record in the Atlantic basin. Read on for details on this potpourri of weather happenings.

After April timidly transitioned into milder weather, May was plenty bold in the thermal department, on multiple occasions behaving more like summer than late spring. Most NJ residents did not seem to mind the warmth; rather, from the second week onward, it was the frequent episodes of rain, often targeting weekends, which raised the level of crankiness among many! Statewide, this was the 5th warmest May since records commenced in 1895. The 65.0° average was 4.5° above the 1981–2010 mean. Five of the ten warmest Mays have occurred since 2004. In most locations, rain fell on at least half of the days of the month. The 5.96” average across NJ was 1.97” above the 1981–2010 mean. This ranks as the 13th wettest May on record, but 0.55” below last year’s average.