Nov 7, 2012 Storm Summary

November 7, 2012 Snowstorm

On November 7, 2012, a moderate snowstorm affected the NYC area with moderate to locally heavy wet snow. Typically, a storm of this magnitude is not unusual, with numerous bigger storms observed over the last few years. This event, however, was made notable due to several factors, including this being the second year in a row the NYC area observed an unseasonably early snowstorm, unusually difficult forecasting of the storm even 1-2 days in advance, and this wet snowstorm coming barely a week after hurricane Sandy devastated the Mid Atlantic coast.

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November 7, 2012 Storm Archive

November 2 - Nor'easter Expected Next Week
November 4 - Rain, Wind Return This Week
November 6 - Snow And Wind Expected Tomorrow
November 7 Storm Updates

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Storm History

Following hurricane Sandy in late October, a strong trough remained in place over the Northeast region through the first week of November; the upper level low exited the region on November 3, but was replaced by another ULL diving into southeastern Canada on November 5-6 while a strong shortwave tracked south through the central US into the interior Southeast, then up the East Coast while interacting with another shortwave to its southwest taking a similar path.

A weak surface low pressure developed off the Southeast coast on the morning of Tuesday, June 6, tracking NNE parallel the coast while quickly intensifying over the next 24 hours to reach a minimum pressure around 988 mb while off the coast of New Jersey on Wednesday. As the track was relatively east, precipitation failed to expand much inland, with the heaviest precipitation mostly confined to coastal areas. The storm became vertically stacked overnight, with the low pressure slowly weakening as it stalled just southeast of Cape Cod, exiting the region on Thursday night.

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Storm Impact in the Northeast

Radar image from 4:48 PM, from the National Weather Service, showing a heavy snow band over the NYC area.

Precipitation began to spread into the area from the southeast in the early morning, reaching the immediate NYC area towards 12 PM. Precipitation was initially in the form of rain especially east and south of NYC, but as temperatures cooled down into the low to mid 30s, a mix of rain/snow and plain snow spread into NYC and locations further north/west around this time. Through the rest of the early-mid afternoon hours, the heavier snow bands continued to advance northwest until stalling at their westernmost point, over the immediate NYC area, focusing over eastern NJ, southeastern NY, southwest CT, NYC, and western Long Island especially over Nassau county, while locations that have been seeing rain mostly changed over to snow. These locations remained under the heavier snow bands through the rest of the evening into the early overnight hours, with the snow not weakening until after 11 PM to 12 AM.

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Forecasting The Storm

(This section has not been completed yet. It is likely to be added in early-mid July.)

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Storm Snow Totals

While this storm was less significant than the October 2011 snowstorm, when a widespread axis of 10+ inches of snow was located north and west of the I-95 corridor, this storm is still notable for its snow totals as it was another unseasonably early snowstorm, only a year after the last such occurrence, and a little more than a week after hurricane Sandy devastated the region.

The higher snow totals with this storm were confined to a relatively narrow axis from east-central NJ into the NYC area and central New England, where over 3-6 inches of snow fell. There were two snow maximum areas; the highest totals with this storm were observed in Clintonville, CT (New Haven county) and Monroe, CT (Fairfield county), with 13.5 inches of snow, with similar totals around the same area. The second highest total from the storm was reported in Monmouth county, NJ, with 13.0 inches of snow in Freehold, NJ.

Some of the higher snow totals from the storm came from locations that were not forecast to receive much, if any accumulations, as the axis of heavier snow was originally expected to be further west, towards western New Jersey and eastern Pennsylvania, which ended up with only minor accumulations. Western to central Long Island were initially expected to receive very little accumulations, but ended up with at least 3 to 6 inches of snow, with totals as high as 8.5 inches in Woodmere and Albertson, NY (Nassau county). Coastal New Jersey was expected to see less accumulations than locations further inland, but the heavier snow bands set up over parts of eastern New Jersey, especially over Monmouth county, where the highest totals in New Jersey were observed. In the immediate NYC area, totals ranged from T-3 inches in far western and eastern areas to 3-6 inches across the immediate NYC area, SE NY and most of Connecticut, with a narrow band of 6-13 inches from western LI/northeast NJ into southwestern and central Connecticut.