National Weather Service United States Department of Commerce

Overview

On December 16-17, 2020, a Nor’easter left behind a large footprint of double-digit snowfall totals across the interior Mid-Atlantic and Northeast regions. The heaviest snow fell in a narrow band that stretched from north-central Pennsylvania to far southeastern Maine. Snowfall totals in excess of 30 inches were reported in this mesoscale snowband with localized amounts exceeding 40 inches across the Southern Tier of New York, southern Vermont and New Hampshire. Numerous snowfall records were set with this storm including a new storm-total snowfall of 40” at Binghamton, New York. While the sheer amount of snow was extraordinary by itself, the short duration and intense snowfall rates adds to the remarkability of this event. Snowfall rates of 4 to 6 inches per hour for much of the night and early morning on 17 December resulted in snowfall totals near three feet in 12 hours. This amount of snow in a short period of time caused roads to become nearly impassible as snow plows could not keep up and even in some instances became stuck.

Below is a map showing preliminary snowfall amounts across these areas. Click on map for a larger view.

Map showing snowfall amounts across parts of NY and PA

Here is a zoomed in version of the snowfall map focused on the Binghamton, NY forecast warning area. Click on map for a larger view.

Map showing snowfall amounts across parts of NY and PA

 

Click to view snowfall reportsExpandCollapse


...SNOWFALL REPORTS...

Location                     Amount    Time/Date       Provider

...New York...

...Broome County...
2 SW Nws Binghamton          42.0 in   1028 AM 12/17
1 SSW Port Crane             41.0 in   0945 AM 12/17   Public
Endwell                      41.0 in   0859 AM 12/17   Trained Spotter
2 E Vestal                   41.0 in   0830 AM 12/17   NWS Employee
2 S Binghamton               41.0 in   0800 AM 12/17   Public
Endicott                     40.5 in   0550 AM 12/17   Trained Spotter
Nws Binghamton               40.0 in   0100 PM 12/17   Official NWS Obs
2 SW Vestal Center           40.0 in   0730 AM 12/17   NWS Employee
West Corners                 39.5 in   0649 AM 12/17   Public
Vestal                       37.9 in   0927 AM 12/17   Trained Spotter
Johnson City                 37.5 in   0858 AM 12/17   Trained Spotter
Chenango Bridge              36.0 in   0742 AM 12/17   Public
Chenango Forks               35.0 in   0415 AM 12/17   Public
2 SSE Vestal Center          35.0 in   0747 AM 12/17   Public
1 WSW Endwell                35.0 in   0510 AM 12/17   Public
1 SSW Port Dickinson         33.0 in   1249 PM 12/17
1 W Port Dickinson           32.0 in   0630 AM 12/17   Trained Spotter
2 NNE Johnson City           31.0 in   0500 AM 12/17   Public
Binghamton                   30.0 in   0925 AM 12/17   Trained Spotter
Lisle                        30.0 in   0626 AM 12/17   Public
Chenango Forks 3.0 SE        29.8 in   0800 AM 12/17   COCORAHS
1 SW Chenango Bridge         29.0 in   0830 AM 12/17   Public
Nanticoke                    29.0 in   0636 AM 12/17   Public
1 WSW West Corners           28.5 in   0245 AM 12/17   NWS Employee
0.7 N Whitney Point          28.0 in   1000 AM 12/17   COOP
Binghamton 1.3 ENE           27.5 in   1000 AM 12/17   COCORAHS
2 SE Union Center            27.0 in   0225 AM 12/17   NWS Employee
Kirkwood                     24.0 in   0625 AM 12/17   Public
2 ENE Lisle                  23.0 in   0721 AM 12/17   Public
Whitney Point                21.0 in   0157 AM 12/17   Public
Windsor                      20.5 in   1234 PM 12/17   Public

...Cayuga County...
Aurora 2.4 N                 5.2 in    0800 AM 12/17   COCORAHS
Auburn 8.3 SSE               5.2 in    0600 AM 12/17   COCORAHS
Auburn                       4.8 in    0600 AM 12/17   COOP
2.0 N Cayuga                 4.0 in    0645 AM 12/17   COOP
Union Springs                4.0 in    0530 AM 12/17   Public
Cayuga 4.0 NNE               3.3 in    0700 AM 12/17   COCORAHS

...Chemung County...
2 NW Waverly                 31.0 in   0811 AM 12/17   Public
2 WSW Waverly                27.5 in   0700 AM 12/17   Trained Spotter
4 W Waverly                  23.0 in   0900 AM 12/17   Public
Van Etten                    23.0 in   0730 AM 12/17   Public
Elmira                       21.5 in   0715 AM 12/17   Public
1 NE Southport               20.0 in   0845 AM 12/17   Public
Elmira                       19.0 in   0700 AM 12/17   Public
Elmira 0.7 WNW               19.0 in   0650 AM 12/17   COCORAHS
1.0 NE West Elmira           18.7 in   0700 AM 12/17   COOP
1 SSE Horseheads             18.0 in   1112 AM 12/17   Trained Spotter
Southport                    18.0 in   0820 AM 12/17   Public
Horseheads                   16.0 in   0841 AM 12/17   Broadcast Media
3 NNE Swartwood              15.4 in   0700 AM 12/17   Public
Erin                         15.0 in   0847 AM 12/17   Trained Spotter
1 ESE Horseheads North       13.0 in   0200 AM 12/17   Broadcast Media

...Chenango County...
Oxford 0.8 NNW               35.0 in   0800 AM 12/17   COCORAHS
3 NE Norwich                 34.0 in   1030 AM 12/17   Public
Greene                       34.0 in   0700 AM 12/17   Trained Spotter
Oxford                       33.0 in   0700 AM 12/17   Trained Spotter
Norwich 5.4 W                30.0 in   0700 AM 12/17   COCORAHS
Preston                      29.0 in   0700 AM 12/17   Trained Spotter
Norwich                      28.0 in   0706 AM 12/17   Trained Spotter
Bainbridge                   28.0 in   0700 AM 12/17   Trained Spotter
1 N Mt Upton                 25.0 in   0455 AM 12/17   Public
Coventry                     22.0 in   0535 AM 12/17   Public
Plymouth                     22.0 in   0700 AM 12/17   Trained Spotter
North Norwich                21.0 in   0704 AM 12/17   Trained Spotter
Sherburne                    21.0 in   0456 AM 12/17   Public
Smyrna                       19.0 in   0705 AM 12/17   Trained Spotter

...Cortland County...
Marathon                     24.5 in   1100 AM 12/17   Public
Freetown 1.0 NE              16.0 in   0700 AM 12/17   COCORAHS
2 N Harford                  15.0 in   0515 AM 12/17   Public
2 NW Mcgraw                  12.3 in   0957 AM 12/17
Cortland                     12.0 in   1107 AM 12/17   Trained Spotter
Scott                        12.0 in   0858 AM 12/17   Trained Spotter
Cortland West                12.0 in   0600 AM 12/17
Homer                        9.5 in    0900 AM 12/17   Trained Spotter

...Delaware County...
2 S Kortright                41.0 in   0703 AM 12/17   Trained Spotter
Davenport                    38.0 in   0703 AM 12/17   Trained Spotter
Franklin                     36.0 in   0640 AM 12/17   Public
Sidney                       30.0 in   0900 AM 12/17   Public
Davenport Center             27.0 in   0830 AM 12/17   Public
Meridale                     27.0 in   0704 AM 12/17   Trained Spotter
1 SE Sidney                  25.0 in   0745 AM 12/17   Trained Spotter
Walton 6.5 W                 23.4 in   0700 AM 12/17   COCORAHS
2 S Delhi                    23.0 in   0800 AM 12/17   CO-OP Observer
2 NW Fishs Eddy              21.2 in   1043 AM 12/17
Hobart 4.8 ESE               21.0 in   0700 AM 12/17   COCORAHS
Fleischmanns 5.7 N           17.4 in   0700 AM 12/17   COCORAHS
Hancock                      16.0 in   0758 AM 12/17   Public
Long Eddy 6.5 NNE            15.7 in   0800 AM 12/17   COCORAHS
4 NW Cooks Falls             15.0 in   1019 AM 12/17

...Madison County...
South Brookfield             22.0 in   0700 AM 12/17   Public
Hamilton                     18.0 in   0718 AM 12/17   Public
Erieville                    13.2 in   1038 AM 12/17   Trained Spotter
Nelson                       11.5 in   0915 AM 12/17   Public
Oneida                       10.0 in   0857 AM 12/17   Trained Spotter
Cazenovia 2.9 SE             9.5 in    0700 AM 12/17   COCORAHS
3 SE Perryville              7.8 in    0800 AM 12/17   Trained Spotter
1 WSW Sherrill               7.5 in    0944 AM 12/17   Public
Chittenango                  6.0 in    0736 AM 12/17   Trained Spotter
1 ENE Sullivan               5.6 in    0922 AM 12/17
Chittenango 2.1 ESE          5.0 in    0800 AM 12/17   COCORAHS

...Oneida County...
1 W Sauquoit                 10.7 in   0643 AM 12/17   Trained Spotter
Utica                        10.5 in   1125 AM 12/17   Broadcast Media
1 SE Clinton                 10.5 in   1003 AM 12/17   Trained Spotter
3 S Utica                    10.0 in   0907 AM 12/17   Public
Deerfield                    9.5 in    1030 AM 12/17   Public
Paris                        9.2 in    1048 AM 12/17   Trained Spotter
New Hartford                 9.1 in    0601 AM 12/17   Trained Spotter
Westmoreland 4 N             8.0 in    0700 AM 12/17   COOP
Sherrill                     8.0 in    0645 AM 12/17   Public
Holland Patent 1.1 WNW       7.0 in    0700 AM 12/17   COCORAHS
Durhamville 3.5 NNW          6.3 in    0700 AM 12/17   COCORAHS
Rome                         6.0 in    0700 AM 12/17   Trained Spotter
1 WSW Griffiss Afb           6.0 in    0700 AM 12/17   Trained Spotter
Point Rock 0.6 SE            4.1 in    0730 AM 12/17   COCORAHS

...Onondaga County...
Jamesville                   6.0 in    0845 AM 12/17   Trained Spotter
Skaneateles 9.1 SE           6.0 in    0700 AM 12/17   COCORAHS
Marcellus                    5.2 in    0811 AM 12/17   Trained Spotter
Syracuse                     5.0 in    0849 AM 12/17   Trained Spotter
Camillus 1.0 W               4.8 in    0700 AM 12/17   COCORAHS
Syracuse 2.7 S               4.7 in    0730 AM 12/17   COCORAHS
Skaneateles 0.8 NNW          4.2 in    0710 AM 12/17   COCORAHS
Westvale                     4.0 in    0541 AM 12/17   Broadcast Media
Clay 4.6 NW                  3.5 in    0830 AM 12/17   COCORAHS
Baldwinsville 3.3 NE         3.5 in    0800 AM 12/17   COCORAHS
Brewerton 1.5 ESE            3.4 in    0815 AM 12/17   COCORAHS
Baldwinsville                3.3 in    0900 AM 12/17   Trained Spotter
Liverpool 4.5 N              3.2 in    0720 AM 12/17   COCORAHS
Brewerton Lock 23            3.0 in    0700 AM 12/17   COOP

...Otsego County...
Unadilla                     31.4 in   0838 AM 12/17   Trained Spotter
Gilbertsville                28.0 in   1045 AM 12/17   Public
Emmons                       27.1 in   0926 AM 12/17   Trained Spotter
Schenevus                    27.0 in   0702 AM 12/17   Trained Spotter
Maryland                     26.0 in   0630 AM 12/17   Public
2 NNW Emmons                 25.5 in   0718 AM 12/17   Public
Otego                        25.0 in   0955 AM 12/17   Public
Otego                        25.0 in   1000 AM 12/17   Public
Hartwick                     24.7 in   0930 AM 12/17   COCORAHS
1 NNE Oneonta                24.5 in   1202 PM 12/17   Trained Spotter
Oneonta                      24.0 in   0800 AM 12/17   Public
Edmeston                     24.0 in   0550 AM 12/17   Public
3 NE Mt Vision               20.5 in   0500 AM 12/17   Public
Cooperstown                  19.0 in   0705 AM 12/17   Trained Spotter
Unadilla Forks               17.0 in   0600 AM 12/17   Public

...Schuyler County...
Mecklenburg 4 SW             12.0 in   0700 AM 12/17   COOP
1 WNW Odessa                 11.8 in   1243 PM 12/17   Public
Smith Valley 1.9 SE          11.4 in   0700 AM 12/17   COCORAHS
1 SSE Burdett                10.0 in   0630 AM 12/17   Trained Spotter
Catharine                    9.8 in    1108 AM 12/17   Trained Spotter
Dundee 6.2 E                 7.5 in    0700 AM 12/17   COCORAHS

...Seneca County...
Fayette                      5.3 in    0753 AM 12/17   Public

...Steuben County...
Caton                        18.0 in   0625 AM 12/17   Public
Addison                      14.0 in   0749 AM 12/17   Public
Corning                      14.0 in   0700 AM 12/17   Trained Spotter
Painted Post 0.7 SSE         13.8 in   0600 AM 12/17   COCORAHS
Campbell                     13.0 in   0802 AM 12/17   Public
Prattsburg                   11.0 in   0830 AM 12/17   Trained Spotter
Sonora                       11.0 in   0800 AM 12/17   Trained Spotter
Howard                       11.0 in   0740 AM 12/17   Trained Spotter
Canisteo                     11.0 in   0838 AM 12/17   Trained Spotter
Bath 4.2 E                   11.0 in   0700 AM 12/17   COCORAHS
Bath                         10.5 in   1045 AM 12/17   Public
Cohocton                     10.0 in   0800 AM 12/17   Trained Spotter
Kanona                       10.0 in   0700 AM 12/17   Trained Spotter
Avoca                        9.5 in    0736 AM 12/17   Trained Spotter
Hornell                      9.3 in    0825 AM 12/17   Trained Spotter
Arkport                      7.3 in    0832 AM 12/17   Trained Spotter

...Sullivan County...
Kiamesha                     16.5 in   0800 AM 12/17   Public
Woodridge                    15.7 in   0756 AM 12/17   Trained Spotter
Glen Spey                    15.5 in   0700 AM 12/17   Trained Spotter
Wurtsboro                    14.5 in   0755 AM 12/17   Trained Spotter
3 SE Hartwood                14.5 in   0654 AM 12/17   Public
Grahamsville                 14.2 in   0800 AM 12/17   Trained Spotter
Monticello                   12.0 in   0800 AM 12/17   Public
Parksville                   10.5 in   0659 AM 12/17   Trained Spotter

...Tioga County...
2 SE Newark Valley           44.0 in   0700 AM 12/17   Public
1 NNE Tioga Terrace          43.0 in   0945 AM 12/17   Trained Spotter
1 N Foster                   41.2 in   1250 PM 12/17   NWS Employee
Owego                        41.0 in   0815 AM 12/17   Public
2 ESE Campville              40.5 in   0905 AM 12/17
1 ENE Owego                  39.0 in   0915 AM 12/17   Public
3 WNW Foster                 39.0 in   0800 AM 12/17   Public
Apalachin                    38.0 in   0510 AM 12/17   Public
1 NW Tioga Terrace           37.0 in   0730 AM 12/17   Public
Tioga Terrace                37.0 in   1037 AM 12/17   Trained Spotter
Owego                        35.0 in   0700 AM 12/17   Public
Newark Valley                35.0 in   0515 AM 12/17   Public
Waverly                      33.7 in   1019 AM 12/17   Trained Spotter
1 ENE Waverly                28.0 in   1055 AM 12/17
Lockwood                     26.0 in   0631 AM 12/17   Public
Candor                       25.0 in   0900 AM 12/17   Public
Berkshire 2.0 N              25.0 in   0730 AM 12/17   COCORAHS
Berkshire                    25.0 in   0730 AM 12/17   Trained Spotter
Berkshire                    24.8 in   0630 AM 12/17   Public
Candor 1.8 N                 24.5 in   0700 AM 12/17   COCORAHS
2 NNW Berkshire              23.0 in   0858 AM 12/17   Public

...Tompkins County...
Newfield Hamlet 4.3 S        16.0 in   0900 AM 12/17   COCORAHS
Freeville                    16.0 in   0640 AM 12/17   Public
Jacksonville                 14.0 in   0900 AM 12/17   Trained Spotter
3 S Newfield Hamlet          13.9 in   1124 AM 12/17
Danby                        13.0 in   1045 AM 12/17   Public
Ithaca 6.4 E                 13.0 in   0730 AM 12/17   COCORAHS
Ithaca 5.4 SSW               12.8 in   0700 AM 12/17   COCORAHS
Ithaca 1.1 SE                11.3 in   0700 AM 12/17   COCORAHS
1 E Northeast Ithaca         11.0 in   0925 AM 12/17   Trained Spotter
Ithaca                       11.0 in   0750 AM 12/17   Public
Etna                         11.0 in   0730 AM 12/17   Public
Groton                       10.5 in   0730 AM 12/17   Public
Freeville 1.5 NE             10.5 in   0700 AM 12/17   COCORAHS
Groton 3.2 SSW               10.2 in   0800 AM 12/17   COCORAHS
1.1 E Forest Home            10.2 in   0700 AM 12/17   COOP
1 NE Trumansburg             10.0 in   0830 AM 12/17   Public
Ithaca 2.0 ESE               9.8 in    0800 AM 12/17   COCORAHS
Trumansburg 0.4 WNW          9.2 in    0700 AM 12/17   COCORAHS
Lansing                      8.5 in    0933 AM 12/17   Trained Spotter

...Yates County...
Branchport                   10.0 in   0851 AM 12/17   Trained Spotter
Italy Hill                   8.5 in    0500 AM 12/17   Public
Middlesex 3.5 S              7.0 in    0900 AM 12/17   COCORAHS
Penn Yan                     6.0 in    0445 AM 12/17   Public
Benton                       5.0 in    0942 AM 12/17   Trained Spotter

...Pennsylvania...

...Bradford County...
3 ENE Alba                   43.3 in   0700 AM 12/17   Public
Burlington 6.1 SW            36.0 in   0445 AM 12/17   COCORAHS
Troy                         36.0 in   0600 AM 12/17   Public
Rome                         34.8 in   0730 AM 12/17   Public
Litchfield                   34.0 in   1045 AM 12/17   Public
Sayre                        34.0 in   0900 AM 12/17   Public
1 NE Sayre                   33.0 in   0903 AM 12/17
Ridgebury                    31.0 in   0647 AM 12/17   Public
Towanda                      28.0 in   0947 AM 12/17   CO-OP Observer
Alba                         26.0 in   0420 AM 12/17   Trained Spotter
3 W South Branch             23.0 in   1132 AM 12/17   Trained Spotter
3 WSW Browntown              20.0 in   0456 AM 12/17   Public

...Lackawanna County...
East Benton                  20.0 in   0700 AM 12/17   Public
Vandling 0.1 NNE             14.0 in   0700 AM 12/17   COCORAHS
Olyphant                     11.2 in   0830 AM 12/17   Trained Spotter
1 NE Moosic                  11.0 in   0945 AM 12/17   Official NWS Obs
Scranton                     11.0 in   0713 AM 12/17   Public
Clarks Green 0.5 N           10.8 in   0930 AM 12/17   COCORAHS
Moosic                       10.6 in   0735 AM 12/17   Trained Spotter
Clarks Summit                10.0 in   0740 AM 12/17   Public
Clarks Summit                9.7 in    0530 AM 12/17   Trained Spotter
1 E West Scranton            9.3 in    0712 AM 12/17   Trained Spotter
Throop                       9.3 in    0830 AM 12/17   Public
Dickson City                 6.8 in    1040 AM 12/17   Trained Spotter

...Luzerne County...
1 S Harveys Lake             20.0 in   0935 AM 12/17
Harveys Lake                 17.5 in   0900 AM 12/17   Trained Spotter
Sweet Valley                 17.0 in   0700 AM 12/17   Trained Spotter
1 SW Wilkes-Barre            15.0 in   1037 AM 12/17
1 NNW West Pittston          15.0 in   1028 AM 12/17
Exeter                       15.0 in   1020 AM 12/17   Trained Spotter
Ashley                       15.0 in   0800 AM 12/17   Public
1 NNW Sugar Notch            14.5 in   0830 AM 12/17   Public
Edwardsville                 14.2 in   0700 AM 12/17   Trained Spotter
Shavertown                   14.0 in   0830 AM 12/17   Public
Lehman                       14.0 in   0700 AM 12/17   Trained Spotter
Mountain Top 1.0 SW          12.7 in   0950 AM 12/17   COCORAHS
Harveys Lake                 12.0 in   0530 AM 12/17   Trained Spotter
Forty Fort                   12.0 in   0900 AM 12/17   Public
1 NNW Courtdale              12.0 in   0800 AM 12/17   Public
Dallas                       12.0 in   0700 AM 12/17   Trained Spotter
Drums                        11.8 in   1045 AM 12/17   Trained Spotter
1 NW Ashley                  11.4 in   0700 AM 12/17   Trained Spotter
Duryea 0.3 SE                11.0 in   0500 AM 12/17   COCORAHS
Pittston                     11.0 in   0700 AM 12/17   Public
1 SE Albert                  10.0 in   0619 AM 12/17   Public

...Pike County...
Milford 8.7 NW               11.5 in   0700 AM 12/17   COCORAHS
Blooming Grove               10.5 in   0626 AM 12/17   Trained Spotter

...Susquehanna County...
Hallstead                    31.5 in   0858 AM 12/17   Trained Spotter
Susquehanna                  23.5 in   0900 AM 12/17   Trained Spotter
New Milford                  22.0 in   0900 AM 12/17   Trained Spotter
1 NE Susquehanna             22.0 in   0836 AM 12/17   Trained Spotter
Lenoxville                   21.5 in   0217 AM 12/17   Public
New Milford 1.6 SSE          21.0 in   0915 AM 12/17   COCORAHS
2 ESE Birchardville          19.5 in   0813 AM 12/17   Public
Harford 1.4 NNE              18.9 in   0730 AM 12/17   COCORAHS
1 N Montrose                 18.0 in   0400 AM 12/17   Public
1 WNW Montrose               16.0 in   0900 AM 12/17   Trained Spotter
Forest City                  14.0 in   0630 AM 12/17   Public

...Wayne County...
Damascus                     18.0 in   0600 AM 12/17   Trained Spotter
Lakewood                     16.0 in   0621 AM 12/17   Trained Spotter
Equinunk                     15.0 in   0621 AM 12/17   Trained Spotter
2 W Hawley                   14.0 in   1100 AM 12/17   Trained Spotter
Hawley                       14.0 in   0901 AM 12/17   Trained Spotter
Honesdale                    13.6 in   1000 AM 12/17   Trained Spotter
Newfoundland                 13.0 in   0625 AM 12/17   Trained Spotter
1 W Greentown                12.9 in   0640 AM 12/17   Public
Dyberry - 19                 12.8 in   0700 AM 12/17   COCORAHS
Prompton                     11.6 in   0700 AM 12/17   COOP

...Wyoming County...
Falls                        16.0 in   0800 AM 12/17   Trained Spotter
Tunkhannock                  15.5 in   0629 AM 12/17   Public
Nicholson                    15.3 in   0645 AM 12/17   Public
Factoryville                 15.0 in   0745 AM 12/17   Trained Spotter
&&

Observations are collected from a variety of sources with varying
equipment and exposures. We thank all volunteer weather observers
for their dedication. Not all data listed are considered official.
THIS WILL BE THE FINAL SUMMARY FOR THIS STORM. Thanks, everyone.

 

This is a loop of the NWS Binghamton, NY WSR-88D radar from 06:57 AM EST (1157 UTC) December 16, 2020 to 12:21 PM EST (1721 UTC) December 17, 2020.

 

The most intense period of snow sets up when a band of higher reflectivity develops in a southwest to northeast orientation over the radar site, shown in yellow. This is where the highest snowfall rates on the order of 3 to 6 inches per hour were occurring. Snowfall amounts ranged from 30 to 45 inches across this area.

 

This is a loop of the GOES East Infrared Satellite Imagery from December 15-18, 2020.

 

The synoptic and mesoscale conditions were highly conducive for a well-developed low pressure system lifting through the Northeast U.S. and an enhanced mesoscale band forming on the back side which produced the intense snowfall rates and swath of heavy snow.

The large scale synoptic pattern at 300 mb was defined by an upper trough lifting east/northeast through the Great Lakes and most of the Northeast U.S. The strong vertical motion was enhanced by a coupled jet, which can be seen on the image to the right as a 150 knot jet streak exits off the North Atlantic coast and a secondary jet rounds the bottom of the trough and noses into the Mid Atlantic. A large portion of the Northeast was situated within the right entrance region of the jet to the north and the left exit quadrant of the jet to the south.

Map showing synoptic pattern at 300mb


The 500 mb pattern was not that unusual either, with a closed low over the Southern Plains becoming an open wave as it moved through the Ohio Valley and through the Northeast. The progressive nature of the wave made the duration of the event relatively short, but that did not hinder the ability of the storm to produce heavy snowfall rates.

Map showing synoptic pattern at 500mb


The 700 mb pattern was defined by an open wave initially, but became a closed circulation early in the morning. The 700mb frontogenesis on the north/northwest side of the circulation become very strong and was one of the forcing mechanisms for the development of the intense snow band.

Map showing synoptic pattern at 700mb


At 850 mb the circulation was closed off through most of the event and tracked from Virginia to just south of Cape Cod. The notable feature at this level that can be seen on this chart to the right is the presence of a very tight thermal gradient (marked by the tight packing of the isotherms (red/warm and blue/cold dashed lines) along the coast). There is also the depiction of a low level moisture source over the Atlantic that likely was entrained into the area of strong vertical motion/forcing across PA/NJ/southern New England.

Map showing synoptic pattern at 850mb


The surface low deepened off the NJ coast during the evening hours of the 16th, but was not that remarkable by Nor'easter standards. The track of the low and the orientation of the wind field to feed Atlantic moisture into the area of strong forcing to the west was likely the strongest contributor to the intensity of the snowfall.

Map showing surface pressure and wind pattern


The following two images depict the presence of two ingredients that are important for the development of conditional symmetric instability (CSI) which was the primary means of producing such an intense band of heavy snow in this event. The red contours indicate 850 mb (top) and 700 mb (bottom) frontogenesis, and the stippled shaded areas are 800-750 mb (top) and (650-500 mb) geostrophic equivalent potential vorticity (EPVg). The presence of F-gen provides the necessary forcing to lift the air parcels to a level where they can tap into positive buoyancy. EPVg below -1 PVU (potential vorticity units) indicates a zone of CSI where enhanced lift can contribute to large vertical motions. When these two elements overlap with eachother, this indicates a strong potential for heavy snow banding, and this can be seen through both of these analyzed layers.

Map showing EPV at 800-750mb and 850mb F-gen

Map showing EPV at 650-500mb and 700mb F-gen

Here are some photos taken from areas in and around Binghamton, NY

Environment Environment Environment Environment
NWS Binghamton, NY. After the storm. Path leading to NWS office. Buried office worktruck.
Environment Environment Environment Environment
Apalachin, NY. Deck in Maine, NY Garage in Maine, NY Johnson City, NY
Environment Environment Environment Environment
Binghamton, NY Oneonta, NY Worcester, NY Binghamton Sports Complex