The snowstorm of December 12 to 16, 2009

The Regional Snowfall Index is NOAA’s ranking of snowstorms east of the Rockies by how much snow fell, over how wide an area and on how many people, region by region: the area and the population above four snowfall thresholds set for each region, weighted against that region’s own history. A storm is scored in each region it reached, on a scale from 1, notable, to 5, extreme.

Events

200

Deaths

2

Injuries

51

Damage

$15,000

Episodes

44

Every winter weather episode the Weather Service filed east of the Rockies in these dates. A few may belong to another system on the same days. Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.

• Cold in Pennsylvania, December 11, 20097 eventsArctic air behind a strong storm system brought wind chill values to between 10 and 15 below zero to the higher elevations of western Pennsylvania, northern West Virginia, and Garrett county Maryland.
• Cold in West Virginia, December 11, 20092 eventsArctic air behind a strong storm system brought wind chill values to between 10 and 15 below zero to the higher elevations of western Pennsylvania, northern West Virginia, and Garrett county Maryland.
• Cold in Maryland, December 11, 20091 eventArctic air behind a strong storm system brought wind chill values to between 10 and 15 below zero to the higher elevations of western Pennsylvania, northern West Virginia, and Garrett county Maryland.
• Lake-Effect Snow in Pennsylvania, December 11, 20091 eventA heavy lake effect snow band produced six to eight inches of snow across northwest Warren County.
• Lake-Effect Snow in New York, December 11 to 12, 20091 eventAn intense lake effect snow band dropped south into the far northern part of Oneida County late Friday afternoon on the 11th, and continued until the early morning hours of the 12th. Storm total snowfall ranged from 8 to 17 inches.
• Winter Storm in Oregon, December 11 to 12, 20094 eventsWith abnormally cold air in place over much of northwest Oregon, a storm system moved over the region, bringing heavy precipitation, which fell as ice over many areas. Many major highways and interstates were closed due to icy conditions causing travel to be treacherous.
• Winter Storm in Washington, December 11 to 12, 20091 eventWith abnormally cold air already in place over much of southwest Washington, a storm system advanced across the region, bringing heavy precipitation, which fell as ice over many areas.
• Winter Storm in California, December 11 to 13, 20092 eventsA winter storm brought one to two feet of snow and strong winds to the higher elevations of the northern Sierra Nevada Mountains.
• Winter Storm in Utah, December 12 to 14, 200913 eventsA series of moist Pacific storm systems moved through Utah over a 3-day period. The storm brought wet, heavy snow to much of the state, with the heaviest snow across both the valleys and mountains of northern Utah.
• Heavy Snow in Idaho, December 12 to 13, 20095 eventsA strong Pacific storm system brought widespread heavy snow to extreme southern and eastern Idaho over the weekend of December 12th and 13th.
• Winter Storm in Montana, December 12 to 13, 20094 eventsAn arctic cold front moving across North Central Montana brought snow and cold temperatures to the area. Snow accumulations in excess of 8 inches were reported.
• Winter Weather in North Carolina, December 12 to 13, 200920 eventsLight freezing rain developed during the evening hours across the mountains and portions of the foothills and piedmont of North Carolina. Ice accretion was mainly limited to elevated surfaces.
• Winter Weather in Georgia, December 12 to 13, 20091 eventLight freezing rain developed during the evening across the mountains of extreme northeast Georgia. Ice accretion was mainly limited to elevated surfaces.
• Extreme Cold in North Dakota, December 12 to 15, 200917 eventsA prolonged period of advisory to warning criteria wind chills occurred across portions of west and central North Dakota from the evening hours of December 12th through the morning hours of December 15th.
• Extreme Cold in North Dakota, December 13, 20098 eventsThe combination of subzero temperatures and a brisk north to northwest wind produced wind chill readings colder than 40 below zero.
• Winter Weather in Virginia, December 13, 200916 eventsLow pressure developed off the Mid-Atlantic coast causing precipitation to develop over Virginia. There was enough cold air in place for precipitation to start off as a wintry mix of sleet and freezing rain.
• Winter Weather in West Virginia, December 13, 200910 eventsLow pressure developed off the Mid-Atlantic coast causing precipitation to develop over eastern West Virginia. There was enough cold air in place for precipitation to start off as a wintry mix of sleet and freezing rain.
• Winter Weather in Maryland, December 13, 200910 eventsLow pressure developed off the Mid-Atlantic coast causing precipitation to develop over Maryland. There was enough cold air in place for precipitation to start off as a wintry mix of sleet and freezing rain across locations to the north and west of Baltimore.
• Extreme Cold in Minnesota, December 13, 20093 eventsThe combination of subzero temperatures and a brisk north to northwest wind produced wind chill readings colder than 40 below zero.
• Winter Weather in Pennsylvania, December 13, 20092 deaths · 13 eventsAs warm air headed north ahead of low pressure moving into the Ohio Valley freezing rain quickly developed across much of eastern Ohio, western Pennsylvania, northern West Virginia, and Garrett county Maryland.
• Winter Weather in Ohio, December 13, 20098 eventsAs warm air headed north ahead of low pressure moving into the Ohio Valley freezing rain quickly developed across much of eastern Ohio, western Pennsylvania, northern West Virginia, and Garrett county Maryland.
• Winter Weather in West Virginia, December 13, 20094 eventsAs warm air headed north ahead of low pressure moving into the Ohio Valley freezing rain quickly developed across much of eastern Ohio, western Pennsylvania, northern West Virginia, and Garrett county Maryland.
• Winter Weather in Maryland, December 13, 20091 eventAs warm air headed north ahead of low pressure moving into the Ohio Valley freezing rain quickly developed across much of eastern Ohio, western Pennsylvania, northern West Virginia, and Garrett county Maryland.
• Winter Weather in Maryland, December 13, 20091 eventFreezing rain that started during the morning on the 13th led to several accidents across Cecil County, mainly on bridges and overpasses. Temperatures were just cold enough at the start of the precipitation for it to fall as freezing rain.
• Winter Weather in Delaware, December 13, 20091 eventFreezing rain that started during the morning of the 13th led to several accidents across New Castle County, mainly on bridges and overpasses. Temperatures were just cold enough at the start of the precipitation for it to fall as freezing rain.
• Winter Weather in Pennsylvania, December 13, 20098 eventsFreezing rain occurred across most of Eastern Pennsylvania from the morning into the afternoon of the 13th. Ice accretions averaged between one and two tenths and led to many accidents on untreated roadways, bridges and overpasses. Freezing rain began between 8 a.m.
• Winter Weather in New Jersey, December 13, 20095 injured · 5 eventsFreezing rain occurred across most of the Raritan Basin as well as all of northwest New Jersey from the morning into the afternoon of the 13th. Ice accretions averaged between one and three tenths and led to many accidents on untreated roadways, bridges and overpasses.
• Winter Weather in New Jersey, December 13, 20093 eventsLow pressure slowly tracked east across the United States and Canadian border from December 13th 2009 through December 14th 2009, with its trailing cold front slowly pushing through the region.
• Winter Weather in Connecticut, December 13, 200946 injured · 1 eventLow pressure slowly tracked east across the United States and Canadian border from December 13th 2009 through December 14th 2009, with its trailing cold front slowly pushing through the region.
• Winter Weather in Michigan, December 14 to 16, 20092 eventsA northwest flow of Arctic air across Lake Superior continued to support moderate lake effect snow showers over portions of western Upper Michigan from the 14th into the 16th.
• Heavy Snow in Washington, December 14 to 15, 20091 eventA Pacific system brought heavy snow to the south Washington Cascades.
• Heavy Snow in Oregon, December 14 to 15, 20091 eventA Pacific system brought heavy snow to the north Oregon Cascades.
• Cold in Montana, December 14 to 15, 20092 eventsGusty winds along with cold surface temperatures produced very cold wind chill values. Wind chill readings colder than -40 degees Fahrenheit were reported.
• Heavy Snow in Alaska, December 14 to 16, 20091 eventAn area of low pressure developed south of the Kenai Peninsula on the morning of the 14th, and tracked to the Prince William Sound where the low remained quasi-stationary and slowly deepened on the 15th into the 16th.
• Extreme Cold in North Dakota, December 14 to 15, 200910 eventsThe combination of wind speeds holding up in the 10 to 20 mph range and temperatures well below zero sent wind chill readings to 40 below to 50 below zero.
• Winter Storm in California, December 15, 20091 eventA quick moving winter storm brought another round of snow to the far northern Sierra Nevada Mountains.
• Heavy Snow in Idaho, December 15 to 17, 20091 eventFifteen inches of snow fell at the Black Bear SNOTEL site.
• Blizzard in Alaska, December 15 to 17, 20092 eventsA storm in the northern Gulf of Alaska produced heavy snow and localized strong wind. Snow fall totaled over 7 feet in Thompson Pass from December 14th through December 16th. Along with the snow gusty wind created blizzard conditions through the pass.
• Heavy Snow in Alaska, December 15 to 17, 20092 eventsA complex low pressure system was over the entire Gulf of Alaska on the night of 12/15. Low level cold air aided by a north wind persisted over northern SE Alaska into 12/18. The arctic front that oscillated north and south over the Northern Panhandle on 12/18.
• Lake-Effect Snow in New York, December 16 to 17, 2009$15,000 · 1 eventThe winter lake effect season's second storm was a marginal one and restricted mainly to snows off Lake Ontario.
• Lake-Effect Snow in New York, December 16, 20091 eventHeavy lake effect snow occurred from the morning of the 16th to the early evening hours. Snowfall accumulations ranged around 1 foot.
• Heavy Snow in Washington, December 16, 20091 eventMoist southwest flow aloft produced 12 inches of snowfall at Paradise, Mt Rainier, on Dec 16.
• Winter Storm and High Wind in Alaska, December 17 to 18, 200958 kt wind · 2 eventsA storm force low developed off the Queen Charlotte Islands down to 972 MB on Thursday afternoon 12/17 and moved rapidly northward under a southerly jet stream, making landfall around Icy Cape on the morning of 12/18.
• Blizzard in Alaska, December 17, 20091 eventA storm in Prince William Sound produced heavy snow and strong wind in Thompson Pass that resulted in a blizzard through the pass.

The snowstorm of December 7 to 11, 2009The snowstorm of December 18 to 21, 2009Snow nowEvery winter storm filed

NOAA NCEI Regional Snowfall Index, and the Storm Events Database for the episodes.