Monthly Summaries

As spring turns to summer, all in Jersey can be pleased that water supplies are in good shape. Also, while it took some time to become established, by late May, warmer temperatures brought out summer wardrobes. Spring (March–May) conditions will be covered later in this report, but first a look at May. As the title of the monthly portion of this narrative suggests, May 2024 never established a consistent atmospheric pattern. There were plenty of episodes where light to moderate showers dotted the state, but never a broad soaker. Temperatures fluctuated on a weekly basis, without a persistent leaning until warmth prevailed later in the month. Put it all together and May ended on a green note born of somewhat below-normal precipitation and above-normal temperatures. The statewide average temperature of 63.9° was 2.7° above the 1991–2020 normal. This ranks as the 11th mildest May dating back to 1895. This anomaly was driven by elevated minimum temperatures that averaged 54.0° which is 3.8° above normal and ranks as the 4th warmest on record. This no doubt due to persistent nighttime cloud cover. The average high temperature of 73.7° was 1.4° above normal, ranking 35th warmest. The northern climate division averaged 63.0° (+3.1°, 7th warmest). Across the southern division the average temperature was 64.5° (+2.3°, 13th warmest). The coastal division averaged 63.1° (+2.1°, 11th warmest).

So much for March flipping from lion to lamb or vice versa. March 2024 was often a lion throughout, with frequent roaring winds and multiple rain events producing a near-record monthly precipitation total and occasional flooding. The first half of the month ran at a record-warm pace, the monthly average later to be tempered by a second half that was cooler than the first. Still, the month emerged as the 9th mildest on record. Befitting the overall mild conditions, snowfall was scarce to non-existent.

Winds gusted to 35 mph or higher at one or more Rutgers NJ Weather Network (NJWxNet) station on 16 days, exceeding 40 mph on 11 of those days. Precipitation (rain and the water equivalent of the very little snow that fell) averaged 7.76” across the state. This is 3.56” above the 1991–2020 normal and ranks as the third wettest March since records commenced in 1895. The northwest was least wet with 6.00”–7.00” falling. Totals increased to the southeast where near coastal areas received 9.00”–10.00”. The northern climate division averaged 7.01” (+3.00, 6th wettest), the southern division 8.15” (+3.83”, 3rd wettest), and the coastal division 8.98” (+4.56, 2nd wettest).

The statewide average March temperature was 46.0°. This is 5.0° above normal and ranks as the 9th mildest of the past 130 years. The average high temperature of 55.6° was 4.7° above normal and ranks 10th mildest. The average low of 36.3° was 5.1° above normal and ranks 4th mildest. The northern division averaged 43.9° (+5.1°, 9th mildest), southern division 47.2° (+4.8°, 8th mildest), and coastal division 47.0° (+4.8°, 7th mildest).

The first month of 2024 provided a potpourri of weather happenings, including excessive rainfall and flooding, multiple snowfalls, frequent strong winds, frigid days, occasional warmth, and culminating with persistent dismal (aka damp, cloudy) conditions. Something for anyone or perhaps not favored conditions for most people. Totaling up the multiple precipitation episodes, this month emerged as the 6th wettest January on record dating back to 1895. It was the wettest January in 25 years and follows this past December, which was the wettest on record. The statewide 6.39” of rain and melted snow was 2.90” above the 1991–2020 normal. The northern climate division averaged 6.70” (+3.20”, 5th wettest), the southern division 6.18” (+2.71”, 7th wettest), and the coastal division 6.48” (+2.97”, 6th wettest).

January snowfall averaged 7.0” across NJ. This is just 0.2” below normal and ranks as the 53rd snowiest January of the past 130 years. Snow divisions include the north, which averaged 8.9” (-0.5”, 52nd snowiest), central coming in with 5.9” (-1.8”, 65th snowiest), and south with 6.6” (+0.9”, 43rd snowiest).

Temperatures fluctuated throughout the month, ultimately averaging 34.7° statewide. This was 3.0° above normal and ranks as the 20th mildest January. The north averaged 32.3° (+3.4°, 17th mildest), south 36.1° (+2.7°, 22nd mildest), and coast 36.9° (+2.5°, 24th mildest). The statewide average maximum of 42.0° was 1.7° above normal, ranking as the 30th warmest. The statewide average minimum of 27.4° was 4.2° above normal, ranking 16th mildest.

The dry first three weeks of November kept everyone waiting and wondering if a record dry month might be at hand along with increasing drought concerns. To the rescue came two rain events on the 21st–22nd and 26th to bring the monthly average precipitation to a rather respectable total. The statewide average of 2.68” was 0.68” below normal, ranking 52nd driest of the past 129 Novembers. Unlike recent months, it was the coastal northern counties that were driest, while the central north was wettest. The northern division (Hunterdon-Somerset-Union counties northward) averaged 2.92” (-0.55”, 50th driest), the southern division (Mercer-Middlesex-Monmouth counties southward, except along the coast) 2.56” (-0.73”, 53rd driest), and the coastal division (roughly the Garden State Parkway to the coast) 2.24” (-1.10”, 42nd driest).

Snowflakes were seen in a few northern locations on the 1st, a dusting occurred at higher elevations at the start of the 21st–22nd rain event, and flurries and a few measurable dustings from squalls occurred on the 28th. Despite the scattered dustings, regionally and statewide records show an absence of accumulation. This is 0.5” below normal but has been seen in 52 of the previous 128 Novembers.

Fall and spring months are considered to be seasonal transition ones. At times, the change of season takes place rather slowly. Then there are months like this past September when the turn is quite abrupt. September 2023 began with the hottest day and week of 2023. Several rainy periods, some with severe storms, ensued as temperatures began to decline and Hurricane Lee, while remaining far offshore, brought rough surf and some clouds to NJ. Soon after came chilly conditions with the remnants of Tropical Storm Ophelia twice bringing heavy rain into portions of the state and over a week of minor to occasional moderate coastal flooding at times of high tide.

Statewide, the average temperature of 68.1° was 1.2° above the 1991–2020 normal. This ranked as the 16th warmest September since records commenced in 1895. The average high temperature was 77.4°, which 0.2° above normal and ranks 35th warmest. The average low temperature of 58.8° was 2.2° above normal, ranking 8th warmest. The northern climate division averaged 65.8° above (+0.9°, 21st warmest), southern +69.5° (+1.4°, 14th warmest), and coastal 69.9° above (+1.2°, 14th warmest).

September rainfall was excessive, with the southwest and northwest the driest regions of the state yet averaging above the statewide 30-year normal. The wettest area was along the northern coast with rainfall as much as 3 to 4 times above the climatological mean. Statewide, September precipitation averaged 7.55”, which is 3.39” above normal and ranks as the 9th wettest. The northern division averaged 7.73” (+3.27”, 11th wettest), southern 7.38” (+3.39”, 11th wettest), and coastal 8.01” (+4.12”, 3rd wettest).