A Return to Normalcy
November 2007 and Fall Overview
New Jersey State Climatologist
Center for Environmental Prediction, Cook College/NJAES, Rutgers University
December 5, 2007
Following the record warmth of October, November temperatures seemed downright frigid across the Garden State. Finally, leaves were convinced to drop as the temperature averaged 43.9°, which was 1.0° below normal. This is very close to the median temperature for the month, meaning that approximately half of the Novembers back to 1895 have been colder and half warmer. Thanksgiving (22nd) was the warmest day of the month, with afternoon temperatures in the 60s and low 70s ahead of a potent cold front. Just two days later the coldest morning of the month saw temperatures in the teens and 20s. This was the first day this fall that temperatures along portions of the immediate coast dropped below freezing (Harvey Cedars reached 29°). At Walpack, the 12° low that morning marked the 27th sub-freezing low to that date at that Sussex County valley location.
November precipitation was below normal across NJ. On average, 2.12" fell, which is 1.59" below normal. Approximately 2.50" to 3.50" of rain and melted snow fell in northern counties, while southern and central areas commonly received between 1.00" and 2.00". With one month remaining in 2007, a mixed picture in annual precipitation remains in place, with extreme southern counties running about 4" below average for the first 11 months and northern counties close to 4" above average. Only Mercer and Monmouth counties are within 1.1" of the 11-month historic average.
The first measurable snow of the season fell on the hills of northern NJ on the 10th. High Point was the big winner with 4.8", while totals under an inch or two were more common in lower elevations and in the Highlands. A more widespread mantle of snow covered areas of north Jersey, mainly above 200 or 300 feet on the 18th into the 19th (a few lower areas in Essex and Union counties received several tenths of an inch). Among the more impressive totals were 4.5" at Hackettstown (Warren), 5.2" in Newton (Sussex), 6.0" at Tewksbury (Hunterdon) and Chester (Morris) and 6.4" in Marcella (Morris) (see the link near the top right of the ONJSC web page for a listing of reports from these events and all others of note this winter season).
This past fall (September - November) was one of above-average warmth and sub-average precipitation. The excessive warmth of September and October was not balanced by November's cooler than average conditions. Thus fall temperatures averaged 58.2°, or 3.3° above average, making this season the 3rd warmest on record (back to 1895). The early and mid season warmth led to one of the latest, if not the latest, leaf drop on record over the Garden State.
Fall precipitation was below average, thanks to the third driest September on record and a dry November. Only October's 1.58" positive departure kept this season from being closer to record low status and ceased the steady decline in reservoir levels. As it was, this fall was the 31st driest on record.
The National Weather Service's long range forecasting team has issued an outlook for the December 2007 - February 2008 period. For NJ, they project a better chance of temperatures being above average than below and for the southern half of the state, precipitation being more likely to be below than above average. Northern precipitation has equal chances of being in the lower, middle or upper third compared to long term means. This outlook is in large part a result of a moderate to strong La Niña event underway in the tropical Pacific. Such occurrences in the past have resulted in conditions similar to what is projected for NJ this winter.
As difficult as it is to forecast temperature and precipitation, seasonal outlooks for snowfall are even more suspect. However, La Niña winters present perhaps the best opportunity to make a NJ snow forecast, and for snow lovers it isn't the best of one. History has shown that more than two thirds of past La Niña winters have had less than average snowfall across NJ. Depending on how one determines what constitutes a La Niña winter (there are several means of doing so), as few as one out of the past nine events resulted in above average snowfall in New Brunswick. Stay tuned to see what actually transpires!
Past Climate Summaries