Snow Fall Analysis for November 19, 2016

screen-shot-2016-11-20-at-8-53-03-amOn the evening of November 19, 2016; a strong cold front will moved through the Great Lakes, Mid Atlantic, and New England with a line of heavy showers than change over to snow as temperatures at the surface fell over 30 degrees from the mid to upper 60’s into the lower to mid 30’s, which was expected.  However, what was not expected was measurable snowfall over portions of northeastern Pennsylvania, northwestern New Jersey, the Hudson River Valley, and northwestern Connecticut.

screen-shot-2016-11-20-at-8-42-30-amThe snowfall was able to accumulate in these locations, especially above 500 feet, due to stronger than expected cyclogenesis over the Long Island Sound.  The support for this secondary low pressure development can be found in the upper and mid levels of the atmosphere and transferred down to the lower and boundary layers of the atmosphere as the evening progressed.

Above is last night at 300 MB which shows a negatively tilted trough with a jet streak over New England.  As a result, strong divergence is found over the Northern Mid Atlantic and Southern New England supporting rapidly rising air in the atmosphere.

screen-shot-2016-11-20-at-8-40-35-amSo we know that the upper level environment was favorable for rapidly rising air, but what really allowed for rapid cooling of the lower level of the atmosphere was the strong frontogenesis at the mid levels of the atmosphere.  This strong frontogenesis, which can be seen above, leads to rapid cooling of the atmosphere and support deformation in the atmosphere.  The combination of the negatively titled trough leading to divergence at 250 MB/300 MB combined with frontogenesis from 500 MB to the surface all combined to produce rapid lifting of the atmosphere which supports heavy precipitation and rapid cooling.  The combination of those factors with 850 MB temperatures falling 12C from ahead to behind the frontal passage, supporting the development of heavy, wet snowfall.

As such, due to the lifting behind the cold front, called an anafront, the snowfall was able to accumulate as the boundary layer, lower levels, and mid levels all rapidly cooled at the same time.

SNOW FALL RESULTS:

********************STORM TOTAL SNOWFALL********************

LOCATION          STORM TOTAL     TIME/DATE   COMMENTS
                     SNOWFALL           OF
                     /INCHES/   MEASUREMENT

CONNECTICUT

...FAIRFIELD COUNTY...
   NEW CANAAN             0.6   543 AM 11/20  TRAINED SPOTTER
   SHELTON                0.3   720 AM 11/20  PUBLIC

NEW JERSEY

...ESSEX COUNTY...
   CEDAR GROVE            0.5   300 AM 11/20  PUBLIC

...PASSAIC COUNTY...
   WEST MILFORD           4.5   330 AM 11/20  1100 FT ELEVATION.

NEW YORK

...ORANGE COUNTY...
   SALISBURY MILLS        5.0   825 AM 11/20  PUBLIC
   2 NW WEST POINT        4.0   145 AM 11/20  TRAINED SPOTTER
   KIRYAS JOEL            3.6   815 AM 11/20  PUBLIC
   ORANGE LAKE            3.0   715 AM 11/20  TRAINED SPOTTER
   NEW WINDSOR            3.0   715 AM 11/20  PUBLIC
   FLORIDA                2.5   700 AM 11/20  PUBLIC

...WESTCHESTER COUNTY...
   POUND RIDGE            1.5   730 AM 11/20  TRAINED SPOTTER

...ALBANY COUNTY...
   KNOX                   6.0   847 AM 11/20  WEATHERNET6
   COLONIE                0.5   921 AM 11/20  WEATHERNET6

...COLUMBIA COUNTY...
   4 NNW HILLSDALE        8.0   800 AM 11/20  TRAINED SPOTTER
   AUSTERLITZ             6.0   755 AM 11/20  WEATHERNET6
   CHATHAM                6.0   726 AM 11/20  WEATHERNET6
   GHENT                  5.0   825 AM 11/20  FACEBOOK
   ANCRAMDALE             3.8   646 AM 11/20  WEATHERNET6
   TAGHKANIC              3.3   802 AM 11/20  WEATHERNET6
   KINDERHOOK             3.0  1102 AM 11/20  TRAINED SPOTTER
   NORTH CHATHAM          0.2   412 AM 11/20  WEATHERNET6

...DUTCHESS COUNTY...
   POUGHQUAG              4.0   615 AM 11/20  PUBLIC
   1 ESE BULLS HEAD       3.0   950 AM 11/20  PUBLIC
   LA GRANGE              2.8   702 AM 11/20  METEOROLOGIST
   SALT POINT             2.0  1032 AM 11/20  TRAINED SPOTTER
   1 SE SPACKENKILL       1.0   610 AM 11/20  TRAINED SPOTTER
   2 NNW LINDEN ACRES     0.3   821 AM 11/20  TRAINED SPOTTER

...FULTON COUNTY...
   PERTH                  4.5   859 AM 11/20  WEATHERNET6
   BROADALBIN             2.5   728 AM 11/20  WEATHERNET6

...GREENE COUNTY...
   WEST KILL              6.5   641 AM 11/20  WEATHERNET6
   HALCOTT CENTER         6.5   706 AM 11/20  WEATHERNET6
   GREENVILLE CENTER      0.5   608 AM 11/20  WEATHERNET6

...HAMILTON COUNTY...
   PISECO                 5.5   809 AM 11/20  WEATHERNET6
   INDIAN LAKE            5.0   721 AM 11/20  WEATHERNET6
   INLET                  4.5   617 AM 11/20  TRAINED SPOTTER
   HOFFMEISTER            4.5   722 AM 11/20  WEATHERNET6
   8 W LONG LAKE          2.0   922 AM 11/20  AMATEUR RADIO
   WELLS                  0.8   635 AM 11/20  WEATHERNET6

...MONTGOMERY COUNTY...
   GLEN                   4.0   833 AM 11/20  WEATHERNET6
   AMSTERDAM              3.5   821 AM 11/20  TRAINED SPOTTER
   PALATINE BRIDGE        2.5   836 AM 11/20  WEATHERNET6

...RENSSELAER COUNTY...
   1 S WEST STEPHENTOWN  10.5  1015 AM 11/20  REPORTS OF WIRES DOWN
   SAND LAKE              7.5   730 AM 11/20  PUBLIC
   BERLIN                 6.0   848 AM 11/20  WEATHERNET6
   WEST SAND LAKE         6.0   945 AM 11/20  AMATEUR RADIO
   NASSAU                 5.0   901 AM 11/20  FACEBOOK
   EAST SCHODACK          3.8   720 AM 11/20  TRAINED SPOTTER

...SARATOGA COUNTY...
   MIDDLE GROVE           6.0   749 AM 11/20  PUBLIC
   MALTA                  0.4   938 AM 11/20  WEATHERNET6

...SCHENECTADY COUNTY...
   DELANSON               4.0   848 AM 11/20  WEATHERNET6
   1 SSW AQUEDUCT         1.1   925 AM 11/20  NWS EMPLOYEE
   SCHENECTADY-GE PLOT    0.5   943 AM 11/20  NWS EMPLOYEE

...SCHOHARIE COUNTY...
   JEFFERSON              7.0   737 AM 11/20  WEATHERNET6
   RICHMONDVILLE          4.2   651 AM 11/20  WEATHERNET6

...ULSTER COUNTY...
   2 ENE PLATTEKILL       4.0   700 AM 11/20  TRAINED SPOTTER
   PHOENICIA              1.0   728 AM 11/20  WEATHERNET6

...WARREN COUNTY...
   1 N WARRENSBURG        0.3   909 AM 11/20  EMERGENCY MNGR

...WASHINGTON COUNTY...
   HEBRON                 0.2   609 AM 11/20  WEATHERNET6

NEW JERSEY

...BURLINGTON COUNTY...
   MOUNT HOLLY WFO          T  1200 AM 11/20  NWS OFFICE

...HUNTERDON COUNTY...
   3 NNE GLEN GARDNER     3.2   700 AM 11/20  COCORAHS
   3 NNE HOLLAND TWP      2.3   625 AM 11/20  COCORAHS
   1 S BETHLEHEM TWP      2.0   700 AM 11/20  COCORAHS
   1 E MOUNTAINVILLE      1.5   845 AM 11/20  ELEV 1000 FT
   4 NW STOCKTON          1.3   700 AM 11/20  COCORAHS
   1 NW CALIFON           1.2   800 AM 11/20  COCORAHS
   3 N LEBANON            1.2   555 AM 11/20  COCORAHS
   4 N CLINTON TWP        1.0   800 AM 11/20  COCORAHS

...MERCER COUNTY...
   EWING                  0.3  1200 AM 11/20  TRAINED SPOTTER

...MIDDLESEX COUNTY...
   METUCHEN               0.5   300 AM 11/20  PUBLIC

...MONMOUTH COUNTY...
   MANASQUAN                T   700 AM 11/20  TRAINED SPOTTER

...MORRIS COUNTY...
   GREEN POND             4.0   800 AM 11/20  TRAINED SPOTTER
   SCHOOLEYS MOUNTAIN     3.5   515 AM 11/20  TRAINED SPOTTER
   2 SW RANDOLPH TWP      3.0   700 AM 11/20  COCORAHS
   4 W WASHINGTON TWP     2.7   700 AM 11/20  COCORAHS
   SUCCASUNNA             2.0   230 AM 11/20  SOCIAL MEDIA
   1 ENE MINE HILL TWP    1.0   700 AM 11/20  COCORAHS

...SOMERSET COUNTY...
   GREEN BROOK TWP        0.6   634 AM 11/20  TRAINED SPOTTER

...SUSSEX COUNTY...
   1 SW HIGHLAND LAKES    6.7   500 AM 11/20  CO-OP OBSERVER
   HIGH POINT             6.5   755 AM 11/20  TRAINED SPOTTER
   VERNON                 6.0   800 AM 11/20  TRAINED SPOTTER
   3 SE HARDYSTON TWP     4.7   800 AM 11/20  COCORAHS
   GLENWOOD               3.0   630 AM 11/20  PUBLIC
   MONTAGUE               3.0   700 AM 11/20  TRAINED SPOTTER
   2 SW FRANKLIN          2.8   800 AM 11/20  CO-OP OBSERVER
   4 NW SUSSEX            2.0   330 AM 11/20  PUBLIC
   HIGHLAND LAKES         2.0  1240 AM 11/20  TRAINED SPOTTER
   2 W ANDOVER TWP        1.7   830 AM 11/20  COCORAHS
   4 SW WANTAGE           0.8   500 AM 11/20  NWS EMPLOYEE
   SUSSEX                 0.5   815 AM 11/20  SOCIAL MEDIA

...WARREN COUNTY...
   ALLAMUCHY              1.6   445 AM 11/20  TRAINED SPOTTER
   OXFORD                 1.5  1000 AM 11/20  TRAINED SPOTTER
   HACKETTSTOWN           0.8   642 AM 11/20  TRAINED SPOTTER
   STEWARTSVILLE          0.6   815 AM 11/20  TRAINED SPOTTER

PENNSYLVANIA

...BERKS COUNTY...
   HUFFS CHURCH           2.0  1100 PM 11/19  TRAINED SPOTTER

...BUCKS COUNTY...
   SPRINGTOWN             1.1   645 AM 11/20  CO-OP OBSERVER

...CARBON COUNTY...
   KIDDER TWP             6.2   145 AM 11/20  TRAINED SPOTTER

...CHESTER COUNTY...
   GLENMOORE              0.1   700 AM 11/20  CO-OP OBSERVER

...LEHIGH COUNTY...
   SALISBURY TWP          2.2  1230 AM 11/20  ELEVATION 870 FEET.
   LEHIGH VALLEY INTL A     T  1200 AM 11/20  ASOS

...MONROE COUNTY...
   BLAKESLEE              5.5   900 AM 11/20  TRAINED SPOTTER
   POCONO SUMMIT          4.0   900 AM 11/20  TRAINED SPOTTER
   MOUNT POCONO           4.0   800 AM 11/20  TRAINED SPOTTER
   CANADENSIS             2.9   700 AM 11/20  CO-OP OBSERVER

...MONTGOMERY COUNTY...
   GILBERTSVILLE          0.3   929 PM 11/19  TRAINED SPOTTER

...NORTHAMPTON COUNTY...
   WILLIAMS TWP           4.0   644 AM 11/20  TRAINED SPOTTER
   FORKS TWP              0.5  1250 AM 11/20  TRAINED SPOTTER