Fall

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."

There were many sides to New Jersey’s October 2015 weather, however, when temperature and rainfall observations were averaged, conditions were quite close to long-term (1981–2010) means. The statewide average temperature of 54.4° was 0.4° below normal. This ranked as the 53rd coolest since 1895 (121 years). Precipitation averaged 4.17", which is 0.24" above normal and ranks as 44th wettest. October was bookended by events that dumped the vast majority of the month’s precipitation, with an extended period of very dry weather in between. This led to a continuation of moderate drought in the northeast, with nearby areas remaining abnormally dry. The late-month rain, which for the first time in many months was heaviest over the driest areas, staved off the need for any further drought deterioration, at least for the time being. The major weather event of the month extended over the first five days, when incessant onshore winds generated the worst beach erosion and back bay flooding since Sandy three years ago, though not nearly in the same ballpark of what Sandy wrought.