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It is always comforting to enter the water demand season, namely summer, with a bit of a hydrological cushion. Such is the case this year across NJ, thanks to ample rain and some late-season snow in recent months. This timely precipitation has eliminated drought concerns that stemmed from drier-than-normal intervals during 2016. As a result of the precipitation deficits, ground water, streamflow, and reservoirs all dropped to precarious levels, thus the issuance last fall of a drought warning by the NJ Department of Environmental Protection over northern NJ and a drought watch in some southern counties. Aside from two reservoirs in west central NJ remaining below average, at the moment all other hydrological signs are positive. However, no one should let their guard down and fail to appreciate the finite nature of our fresh water resources, and how quickly a period of abundance can lapse again into drought.

More will be noted regarding spring (March–May) conditions later in this report. First taking a look at May, New Jersey experienced its 9th wettest on record, with observations extending back to 1895. The statewide average rainfall of 6.62” was 2.63” above the 1981–2010 average and the wettest May since 1990. Frequent clouds and rain resulted in many chilly days, however, a mid-month heat wave was impactful enough such that the average statewide temperature of 59.8° was only 0.7° below the 1981–2010 average. It was the 61st coolest May of the past 123 years, with none cooler since 2008.

With the Northern Hemisphere atmosphere transitioning from winter to spring, March can be a month of frequently-changing weather with pronounced pressure gradients, thus punctuated by windy conditions. This past March was no exception, and in fact, a windier month would be difficult to find. Winds gusted to 50 mph or greater at one or more NJWxNet station on 11 days and between 40–49 mph on four other days. At most locations, the warmest daily average temperature of the month was, of all things, on March 1st, while the first 80° day of the year was on the 25th. In between those warm spells was the largest snowstorm of the year in central and northern locations and two weeks of some of the coldest weather of the winter. Finally, March went out like a lion, with a statewide soaking rainstorm on the 31st.

The statewide monthly average temperature of 38.9° was 1.9° below the 1981–2010 average. This ranks as the 61st coldest of the past 123 Marches. It was the first month with a below-average temperature since last May, which was only 0.3° below average and last April with a 0.1° negative anomaly. While not exceptionally cold, due to the record warm February average of 40.1°, this was only the third time on record when March was colder than the previous February. This occurred previously in 1984 and 1960. The 1960 occurrence was mainly due to March being the second coldest on record, while in 1984, February was 9th mildest and March 10th coolest. On average, March is 7.3° warmer than February. While the cold of March damaged blossoms of some prematurely-blooming trees and flowers, vegetation was not far enough along to result in significant problems.

A progressive weather pattern dating back to last fall continued to hold serve across the eastern US in January. This resulted in temperatures swinging between mild and cold levels and unsettled weather systems moving through often enough to bring precipitation levels close to average but, with one notable exception, not staying around too long to wreak havoc. Overall, it was a mild month, with a statewide average temperature of 36.2°, which is 5.5° above the 1981–2010 mean. This ranks as the 12th mildest January since 1895. It is interesting to note that while 10 of New Jersey’s warmest 15 years have occurred since 2000 and 14 of 15 since 1990, Januaries have not as often kicked off these warm years as much as one might imagine. Only 5 of the 15 mildest Januaries over the 123 year record have occurred since 2000 and just 8 of the 15 mildest since 1990.

Much like the entire fall season, the transition into the cold half of the year was in no great hurry in November. Leaves dropped from ten days to two weeks later than normal, but eventually by the 28th the temperature fell to the freezing mark at West Cape May (Cape May County) and Newark Airport (Essex), these being the last locations in the state to experience their first freeze. A major exception to the slowly-transitioning pattern was the moderate high-elevation snowfall the weekend before Thanksgiving.

Drought conditions continued to be worrisome across the state, even spreading southwards. However, back-to-back heavy rainfall events on the 29th and 30th provided some replenishment to thirsty soils and began adding water to surface reservoirs across central and northern counties. It will be interesting to see if the atmospheric pattern change that delivered the late-month soakings is fleeting or will be longer lasting. Monthly precipitation (rain and melted snow) averaged 2.48” across NJ. This is 1.13” below the 1981–2010 average and is the 43rd driest November since 1895. It is worth noting that most of the National Weather Service stations that go into determining this average report in the morning. Thus the rain that fell later on the 30th is not factored into the monthly average; rather, it will be part of the December total. Snowfall averaged 0.4” for NJ but broken into regions amounted to 1.3” in the north, 0.1” central, and 0” south. The statewide total is average for Novembers between 1981–2010 but 0.7” below the 1894–present average.

Summer warmth continued into September, only beginning to relinquish its grip on the Garden State during the last week of the month. The average statewide monthly temperature of 70.1° was 4.3° above the 1981–2010 mean. This ranks as the 4th warmest September going back to 1895, with five of the eight warmest Septembers occurring since 2005. Seven of the most recent 13 months have ranked in the top 10 for warmth in their respective months.

Monthly rainfall averaged 3.36” across the state, which is 0.69” below average and ranks as the 61st driest of the past 122 Septembers. However, as discussed below, the average this month does not show the wide disparity of rainfall between the northern and southern parts of the state. While concerns for persistent dry conditions continued increasing across most of NJ through mid September, two soakings in the south alleviated worries in this region. Meanwhile, only one event of note produced totals exceeding an inch in much of the north, thus this region remains much too dry. As of the 27th, a good deal of north and central NJ was considered in moderate drought, with the remainder deemed abnormally dry according to the US Drought Monitor. North Jersey remained under a NJ Department of Environmental Protection “drought watch."