Another major La Nina driven storm system, originating largely in the southern branch of the jet stream, crashed through the Northeast, moving slowly, while bringing an enormous amount of moisture over a prolonged period from Saturday March 5 through Monday morning March 7. The brunt of the storm, however, with the greatest impact on the region occurred during the Sunday through Monday morning period when a combination of heavy snow, heavy rain, and significant sleet and freezing rain fell. Storm total rainfall/liquid equivalent precipitation ranged from two to three inches on average. Total snowfall accumulations of 15"-20" occurred on average throughout the Adirondacks, Otsego, and much of Montgomery County, with 6"-10" surrounding that zone which included the rest of the Catskills, Mohawk valley to much of Rutland County, VT. Lesser snow totals of 3"-6" occurred in the Capital Region after rainfall of approximately 1.75" to 2.25" and up to 1/2" of ice accretion. 1"-3" of snow came on the very tail end of the storm in parts of the mid Hudson valley and northern Berkshire County after 2"-4" of rain and icing ranging from .20" to .50".
Impacts:
The Major Snow Zone
Adirondacks-Catskills-Schoharie County-The Mohawk Valley-northern Saratoga, northern Washington, and Rutland Counties
One to two inch per hour snowfall rates developed during the early to mid morning on Sunday in northern Herkimer and Hamilton counties with the snow line moving south into the Mohawk valley, western Catskills, and Schoharie County through the mid to late afternoon. Strong northeast-northeast wind in combination with the heavy snowfall rates produced low visibility and exceptionally hazardous travel conditions from Sunday afternoon through the mid morning on Monday. Scattered power outages were reported due to the combined effects of snow weighting and the strong wind gusts. Minor flooding was also reported in portions of the Mohawk valley as heavy rain preceded the change to snow.
| Photographer: WeatherNet 6 Spotter Chris Hayes Speculator, NY Hamilton County Monday Afternoon March 7, 2011, 17" Storm Total Snowfall |
Photographer: WeatherNet 6 Spotter Sue Buhl Richmondville, NY Schoharie County Monday Afternoon March 7, 2011, 21 " Storm Total Snowfall |
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The Heavy Rain to Ice Zone
Capital Region-Bennington County, VT-the Mid Hudson valley
Rain overspread this zone through Sunday morning becoming heavy at times during the afternoon. Temperatures dropped from around 50° at noon with the passage of a cold front to near 30° by the late afternoon and the evening. Mild air remained in place aloft which set the stage for the change to freezing rain, and eventually a mixture of freezing rain and sleet as colder air deepened slightly aloft along the northern edge of the mix zone through Schenectady, southern Saratoga, southern Washington and southern Bennington counties where sleet accumulations ranged from 3/4" to as much as 3" on average. More of a pure wind driven freezing rain developed from Albany on south and through the mid Hudson valley as a low level cold
air drainage flow set up. Ice accumulations ranged from .10" to as much as .50" with the higher amounts more widespread from eastern Schenectady, southern Saratoga, southern Washington, southern Bennington, Albany, Rensselaer, and Columbia counties. Numerous power outages occurred in this zone from Sunday night through Monday morning as the combination of heavy ice weighting and strong gusty NNE winds brought down tree branches and trees on power lines. Approximately 10,000 National Grid and NYSEG customers in the Capital Region remained without power through Tuesday March 8.
| Photographer: WeatherNet 6 Spotter Spencer Conlin Eagle Bridge Washington County Tuesday Afternoon March 8, 2011, Heavy Icing still on the trees |
Photographer: WeatherNet 6 Spotter Spencer Conlin Eagle Bridge Washington County Tuesday Afternoon March 8, 2011, Heavy Icing still on the trees |
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The Main Flood Zone:
Eastern Ulster, eastern Greene, Columbia, Dutchess, southern Berkshire and Litchfield Counties
Preceding a change to ice and a little snow at the tail end of the storm, exceptionally heavy rain fell in these counties from Sunday afternoon through Sunday night, amounting to 2"-4" on average. Widespread urban and poor drainage flooding was reported as well as basement flooding. Minor to locally moderate flooding of small streams and creeks was also reported as the combined runoff from the rainfall and melting snow was more than sufficient to produce significant rises on the waterways. Several ice jams were reported on area rivers and streams, but no significant flooding resulted from the blockages.
Set-Up-Saturday March 5
This storm largely originated from the southern branch of the jet stream, amplifying as it tracked east across the country. High pressure ridging at the jet stream level in advance of the storm over the eastern half of the country caused a lead low pressure system to initially track west of the St. Lawrence valley Saturday March 5. This track allowed a warm frontal passage Saturday morning with scattered light mixed snow, sleet, and rain showers which all but dissipated by the early to mid morning. A mild air mass flowed into eastern New York and western New England through the day with generally dry conditions and temperatures warming to 45°-50°. An advancing cold frontal zone brought the first steady rain to the Adirondacks from Saturday afternoon through Saturday night with rainfall totals ranging from 1/2" to an 1" by early Sunday morning.
Sunday-Sunday Night March 6-7:
Deep southwesterly flow at the jet stream level along the Atlantic seaboard was in place through Sunday night. The flow through this jet transported an anomalously high amount of gulf of Mexico moisture into the region while also causing the eastward progress of the entire system to slow. This resulted in a prolonged period of very heavy precipitation from central New York through western New England as moisture channeled north along the stalling frontal boundary. The precipitation was further enhanced as a strong upper air trough rotating around the base of the mean jet stream flow amplified as it tracked up the Appalachians causing surface storm to form along the front over the mid Atlantic region. This storm rapidly intensified as it tracked north Sunday night, passing east of the eastern tip of Long Island through Monday morning. The combined effects of the storm's circulation pumping the moisture rich Atlantic air over the increasingly cold dome of low level air over New York and the approaching upper air storm produced strong vertical motions in the atmosphere creating a favorable scenario for heavy precipitation. The surface storm also had the effect of slowing the eastward progress of the heavy snow zone as the circulation blocked the advance of the deep cold air. However, the low level northerly cold air drainage flow increased in response to the deepening low pressure system causing surface temperatures to drop below freezing through the night in the mid Hudson valley causing the heavy rain to change to heavy freezing rain.. A north to northeast wind increased with the approach of the storm, gusting at times from 30-40 mph which produced a dramatic weather event with a heavy wind driven snow in the snow zone to a heavy wind driven sleet and ice storm in the narrow mixed precipitation zone, to a torrential wind driven rain storm in the mid Hudson valley to southern Berkshire and Litchfield counties.
Monday March 7:
Heavy snow persisted in the Catskills, Mohawk valley, and Adirondacks through the morning with a change to snow working into the Capital Region and southern Vermont between 4am and 6am. The change to snow in the mid Hudson valley during the morning was brief as rapid drying occurred on the southwest flank of the storm. The circulation moved well northeast of the region by the early afternoon marking an end to the storm. Strong sinking air in the atmosphere behind the storm blew out the clouds allowing for a sunny and dry afternoon.
WeatherNet 6 Observed Snowfall Distribution for the March 6-7, 2011 Storm
WeatherNet Storm Storm Total Combined Sleet and Snowfall Reports for March 6-7, 2011
| Town | County | Snowfall Report | Town | County | Snowfall Report |
| Pittsfield, MA | Berkshire | 1/2" | Alford, MA | Berkshire | 1/2" |
| Savoy, MA | Berkshire | 1.1" | |||
| Green Island | Albany | 6.5" | Latham | Albany | 5" |
| Knox | Albany | 12" | Colonie | Albany | 5" |
| Albany (NWS) | Albany | 6.1" | East Berne | Albany | 6" |
| Glenmont | Albany | 3" | Preston Hollow | Albany | 6.5" |
| Potter Hollow | Albany | 10" |
Voorheesville | Albany | 5.3" |
| Feura Bush | Albany | 3" | |||
| Chatham Center | Columbia | 3" | Livingston | Columbia | 1.5" |
| Taghkanic | Columbia | 1/2" | Germantown | Columbia | 1.5" |
| Kinderhook | Columbia | 2" | |||
| Arkville | Delaware | 10.3" | Harpersfield | Delaware | 8.5" (4:30am) Not a Total |
| Caroga Lake | Fulton | 11.5" | Gloversville | Fulton | 10" |
| Broadalbin | Fulton | 10.5" | Johnstown | Fulton | 10" |
| Halcott | Greene | 6" | Prattsville | Greene | 12" |
| Ashland | Greene | 12" | Catskill | Greene | 2" to 3" |
| Freehold | Greene | 5.5" | Greenville | Greene | 4" |
| Cairo | Greene | 4" | |||
| Blue Mountain Lake | Hamilton | 23.3" | Indian Lake | Hamilton | 22.5" |
| Wells | Hamilton | 19" | Speculator | Hamilton | 17" |
| Dolgeville | Herkimer | 12" | |||
| Fonda | Montgomery | 10" to 12" | Glen | Montgomery | 15" |
| Hessville | Mongtomery | 19" | Stone Ridge | Mongtomery | 9.3" |
| Amsterdam | Montgomery | 9" to 12.3" | Palatine Bridge | Mongtomery | 15" |
| Maryland | Otsego | 16" | East Worcester | Otsego | 15.5" |
| Cherry Valley | Otsego | 16" | Worcester | Otsego | 15" |
| Schenevus | Otsego | 19" | Oneonta | Otsego | 14.5" |
| Center Brunswick | Rensselaer | 5.8" | Speigletown | Rensselaer | 6" |
| Stephentown | Rensselaer | 1.5" | Berlin | Rensselaer | 0.8" |
| Malta | Saratoga | 6" | Gansevoort | Saratoga | 14" |
| Clifton Park | Saratoga | 5.5" | Milton | Saratoga | 8" |
| Corinth | Saratoga | 11.5" | Charlton | Saratoga | 5.3" |
| Saratoga Springs | Saratoga | 8" to 9.1" | Porter Corners | Saratoga | 13.5" (5am) Not a Total) |
| Edinburg | Saratoga | 8" (5am) Not a Total | |||
| Scotia | Schenectady | 5" | Duanesburg | Schenectady | 12" |
| Princetown | Schenectady | 16.5" | |||
| Richmondville | Schoharie | 21" | Summit | Schoharie | 18" |
| Middleburgh | Schoharie | 19.5" | Schoharie | Schoharie | 13" |
| Esperance | Schoharie | 16" | Huntersland | Schoharie | 12.5" |
| Jefferson | Schoharie | 12" | Seward | Schoharie | 14" |
| Cobleskill | Schoharie | 13.5" | Charlotteville | Schoharie | 13.5" |
| Phoenicia | Ulster | 1.5" | Kingston | Ulster | 0.2" |
| Kerhonkson | Ulster | Trace | Highmount | Ulster | 1" |
| Saugerties | Ulster | 0.2" | Whiteport | Ulster | 1/2" |
| Esopus | Ulster | Trace | |||
| Warrensburg | Warren | 15" | Brant Lake | Warren | 17" |
| Queensbury | Warren | 15" | Lake Luzerne | Warren | 16.5" |
| Granville | Washington | 18" | Cossayuna | Washington | 10.5" |
| Fort Edward | Washington | 15" | Kingsbury | Washington | 15" |
| West Arlington, VT | Bennington | 3" | Landgrove, VT | Bennington | 1.5" |
| Woodford, VT | Bennington | 1.3" | Danby, VT | Rutland | 9.5" |
| West Rutland, VT | Rutland | 12.5" | East Wallingford, VT | Rutland | 10" |
WeatherNet 6-NWS Rainfall/Liquid Equivalent Reports For the Event
| Town | County | Rainfall/Liquid Equivalent Report |
| 2 Miles NNE of Voorheesville | Albany | 2.83" |
| Albany (NWS Office) | Albany | 2.27" |
| Albany (Airport) | Albany | 2.05" |
| Voorheesville | Albany | 1.75" |
| Taghkanic | Columbia | 3.25" |
| Clarksburg, MA | Berkshire | 1.99" (5:30am March 7) Not a Total |
| Stormville | Dutchess | 3.78" |
| Poughkeepsie | Dutchess | 2.80" |
| Red Hook | Dutchess | 2.50" |
| Northville | Fulton | 2.26" |
| Near Gloversville | Fulton | 2.18" |
| Catskill | Greene | 2.45" |
| Near Indian Lake | Hamilton | 2.66" |
| Near Fort Plain | Montgomery | 2.26" |
| Averill Park | Rensselaer | 2.18" |
| Saratoga Springs | Saratoga | 2.24" |
| Niskayuna | Schenectady | 2.02" |
| Kingston | Ulster | 2.78" |
| Esopus | Ulster | 2.00" |
| Phoenicia | Ulster | 4.81" |
| Whiteport | Ulster | 2.60" |
| West Shokan | Ulster | 3.49" |
WeatherNet 6 Observed Ice Distribution for the March 6-7, 2011 Storm
WeatherNet 6-NWS Ice Accumulation Observations For the Event
| Town | County | Ice Accumulation |
| Boght Corners | Albany | 0.30" |
| Feura Bush | Albany | 0.50" |
| Albany (NWS) | Albany | 0.20" |
| 2 Miles NNE of Voorheesville | Albany | 0.10" |
| North Adams, MA | Berkshire | 0.10" |
| La Granville | Dutchess | 0.20" |
| Salt Point | Dutchess | 0.10" |
| Taghkanic | Columbia | 0.40" |
| Chatham Center | Columbia | 0.50" |
| Buskirk | Rensselaer | 0.50" |
| Eagle Mills | Rensselaer | 0.20" |
| Saratoga Springs | Saratoga | 0.10"...3/4" of Sleet |
| Clifton Park (Oaks) | Saratoga | 0.25" to 0.30" |
| Mechanicville | Saratoga | 0.20" to 0.50" |
| 1 Mile NNE Hawthorne Hill | Schenectady | 0.10" |
| North Blenheim | Schoharie | 0.10" |
| Sunderland, VT | Bennington | 0.50" |
| Landgrove, VT | Bennington | 0.50" |
| Esopus | Ulster | Thin Glaze |
| Cossayuna | Washington | 1/8" Ice...3" of Sleet |