New Brunswick, NJ

Weather often varies from week-to-week and even day-to-day during the spring transition season. Such was certainly the case in spring 2021, as will be recapped later in this report. However, when it came to such “weather indecision,” May 2021 took the cake. Starting off somewhat damp with seasonable temperatures, a prolonged period of exceedingly dry weather ensued, first accompanied by cooler-than-normal temperatures and frosty mornings, and later by summer-like heat. As several wildfires broke out and soil moisture vanished, concerns of early-summer drought arose. Then along came one of the coolest Memorial Day weekends on record, accompanied by more than an average May’s worth of rain in some locations. This led to frequent decision making amongst farmers, gardeners, water resource managers, utility companies and customers, and day trippers. All were left wondering what might come next! Cicadas perhaps?

With the thermometer up and down throughout May, the statewide average temperature of 61.0° was just 0.2° below the new 1991–2020 normal. This ranked as the 47th mildest May since 1895. The average maximum of 73.0° was 0.7° above normal, while the 49.0° average minimum was 1.2° below normal. This is illustrative of a month that had many clear days and cool nights with low humidity. Despite dry conditions for most of the month, monthly precipitation came in close to normal, averaging 3.95” across NJ. This is 0.20” above normal, ranking 48th wettest of the past 127 years. Far south and west central areas were driest, while the central coast and northeast saw the most rain. Unlike last May, no snow was observed.

With March being a transitional weather and climate month, there are often pronounced differences in conditions from one day or week to the next. The third month of 2021 did not disappoint in several such respects. Swings in barometric pressure as storms and high pressure systems swung through the Northeast led to 16 days with one or more Rutgers NJ Weather Network stations gusting to 40 mph or higher, with 11 of those days exceeding 50 mph. Maximum temperatures exceeded 65° on 12 days (two days had record highs in some locations), while minimum temperatures fell below 19° on 13 days. Walpack, situated in a Sussex County valley, recorded the state’s lowest (21°) and highest (67°) temperatures on a single day (22nd) and just missed this again on the 30th. There was a two-week interval with virtually no precipitation, culminating in several wildfires on the 14th, yet five events occurred where rain accumulated to 0.98” in one or more locations. Finally, a record of sorts was tied as the statewide average snowfall totaled 0.0”, something observed eight other Marches in the past 127 years. The past two Marches are the only ones with back-to-back zero totals.

Statewide precipitation averaged 4.03”, which is 0.18” below the 1991–2020 average*. This made for the 58th wettest (70th driest) since 1895. Northern NJ was driest, coming in at 3.28” (-0.73, 48th driest), the south averaged 4.47” (+0.15”, 42nd wettest), and the coast 4.68” (+0.26”, 38th wettest). The southeast saw the most rain and northeast and central regions the least (Figure 1).

March temperature average 43.9°, which is 2.9° above the 1991–2020 average and the 14th mildest on record. The average high was 54.7° (+3.8°, 13th mildest) and average low was 33.0° (+1.8°, 19th mildest). The north averaged 41.2° (+2.4°, 19th mildest), south 45.6° (+3.2°, 13th mildest), and the coast 45.1° (+2.9°, 13th mildest).

The first month of 2021 lacked major storms, whether wet or white, and temperatures rarely were either quite mild or very cold. Thus the title of this report. Yes, the last day of the month turned snowy, the harbinger of anything but a boring start to February, but that’s to be covered next month. The January statewide average temperature was 33.7°. This was 3.0° above the 1981–2010 normal and ranks as the 26th mildest January in the past 127 years. The average high was 41.1°, which is 1.8° above normal and ranks 34th mildest, while the average low of 26.3° was 4.2° above normal, ranking 20th mildest.

January precipitation (rain and melted snow) averaged 1.99” across the state, which is 1.41” below normal and ranks 13th driest since 1895. The north averaged 1.93” (-1.48”, 18th driest), the south 2.02” (-1.37”, 13th driest), and the coast 2.19” (-1.25”, 17th driest). Generally, the eastern half of the state was wetter (particularly the northeast) than the west.

For the 12th consecutive year, we in the state climate office have evaluated the myriad daily, monthly, and annual observations gathered across New Jersey during the course of the year to choose what we feel were the most significant and impactful 10 weather and climate events. More about each event can be found in the monthly narratives posted on our website. You might be tempted to rearrange the rankings, particularly as some of the events on the list may have affected you more than others ranked higher. Or perhaps you best recall one that didn't make the list. That's the enjoyment and frustration of lists! Unless stated otherwise, statewide values are based on an average of several dozen stations. The period of record for monthly, seasonal, and annual departures is 1981–2010; while for extremes and rankings it is from 1895–present. Observations are mainly drawn from National Weather Service Cooperative Observing Program stations, Rutgers NJ Weather Network stations, and NJ Community Collaborative Rain, Hail and Snow Network locations.