December 15–17, 2020 nor'easter

North American nor'easter in 2020
December 15–17, 2020 nor'easter
Category 2 "Significant" (RSI/NOAA: 5.58)
GOES-16 satellite image of the nor'easter off the New England coast at 15:56 UTC (10:56 a.m. EST) on December 17, with an eye-like feature
TypeExtratropical cyclone
Nor'easter
Winter storm
Ice storm
FormedDecember 14, 2020
DissipatedDecember 19, 2020
Highest winds
  • 1-minute sustained:
    60 mph (95 km/h)
Highest gust63 mph (101 km/h) in Mantoloking, New Jersey
Lowest pressure995 mb (29.38 inHg)
Tornadoes
confirmed
2 on December 16
Max. rating1EF2 tornado
Duration of
tornado outbreak2
1 hour, 26 minutes
Maximum snowfall
or ice accretion
Snow – 48 in (120 cm) near Danbury, NH
Ice – 0.60 in (1.5 cm) near Pipers Gap, Virginia
Fatalities7 fatalities
Damage> $125 million (2021 USD)[1]
Power outages230,000 in Maine alone[2]
Areas affectedSouthern Plains, Upland South, Southeastern and Northeastern United States (primarily New England and the Mid-Atlantic), Atlantic Canada

1Most severe tornado damage; see Fujita scale
2Time from first tornado to last tornado

The December 15–17, 2020 nor'easter was a powerful nor'easter that hammered the Northeastern United States and produced widespread swaths of over 1 foot (12 in) of snow in much of the region from December 15–17, 2020, ending a 1,000+ day high-impact snowstorm drought in much of the Mid-Atlantic and coastal New England regions. The system developed out of a weak area of low-pressure that first developed over the Central United States producing some snowfall before moving eastward, and by December 16, a new, dominant area of low pressure began to develop along the Southeast coast. This low steadily deepened as it moved along and impacted the Mid-Atlantic coastline, prompting several winter-related advisories and warnings for much of the Northeast.

Multiple states that were expected to be impacted by the nor'easter, including New Jersey, Pennsylvania, and Virginia declared states of emergencies on December 15–16 in advance of the storm. New York and Boston declared a snow emergency the day of the storm as well. The nor'easter brought significant snowfall to metropolitan areas such as New York City, Philadelphia, and Washington, D.C., which eclipsed the entire snowfall total from the previous winter season, as well as Boston and Portland that saw over a foot of snow from the storm. Tens of thousands lost power during the storm, and the storm caused high wind gusts along the Jersey Shore, in addition to rough surf and even storm surge in coastal Massachusetts. At least 7 people have been confirmed killed as a result from the storm, and it is estimated to have caused over $125 million (2021 USD) in damages.[1] The winter storm was rated Category 2 winter storm on the Regional Snowfall Index (RSI) scale, the first such storm for the Northeastern United States since a nor'easter in March 2018.[3] The system was unofficially named Winter Storm Gail by The Weather Channel.[4]

Meteorological history

Map plotting the storm's track and intensity, according to the Saffir–Simpson scale
  Tropical depression (≤38 mph, ≤62 km/h)
  Tropical storm (39–73 mph, 63–118 km/h)
  Category 1 (74–95 mph, 119–153 km/h)
  Category 2 (96–110 mph, 154–177 km/h)
  Category 3 (111–129 mph, 178–208 km/h)
  Category 4 (130–156 mph, 209–251 km/h)
  Category 5 (≥157 mph, ≥252 km/h)
  Unknown
Storm type
circle Tropical cyclone
square Subtropical cyclone
triangle Extratropical cyclone, remnant low, tropical disturbance, or monsoon depression