Great Appalachian Storm of November 1950

Infobox winter storm|name=Great Appalachian Storm of November 1950
image location=Image-19501126sfc.gif


stormtype=Nor'easter
date formed=November 24 1950
date dissipated=November 30 1950
maximum amount=57 inches (145 cm)
pressure=978 mbar (28.88 inHg)
total damages (USD)=$66.7 million (1950 dollars)National Climatic Data Center. [http://www1.ncdc.noaa.gov/pub/orders/A7D756B2-23BA-E264-3117-B74DC625363E.PDF Climatological Data: National Summary 1950.] Retrieved 2006-11-26.]
total fatalities=353
areas affected=Eastern Third of the United States and Southeast Canada

The Great Appalachian Storm of November 1950 was a large extratropical cyclone which moved through the Eastern United States, causing significant winds, heavy rains east of the Appalachians, and blizzard conditions along the western slopes of the mountain chain. Power was out to more than 1,000,000 customers during this event. In all, the storm impacted 22 states, killing 353, and creating US$66.7 million in damage (1950 dollars). [National Oceanic and Atmospheric Administration. [http://www.noaanews.noaa.gov/stories/s334c.htm NOAA'S TOP U. S. WEATHER, WATER AND CLIMATE EVENTS OF THE 20TH CENTURY.] Retrieved on 2006-11-25.] At the time, U.S. insurance companies paid more money out to their policy holders for damage resulting from this cyclone than for any other previous storm or hurricane.

ynoptic history

The preceding atmospheric state was one of La Niña conditions, the cold phase of ENSO, which favors a storm track from the Ohio and Tennessee Valleys into the Appalachians. [Joe D'Aleo. [http://www.intellicast.com/DrDewpoint/Library/1101/ SOME MEMORABLE LA NINA NOVEMBER STORMS.] Retrieved on 2006-11-25.] The cyclone initially formed in southeast North Carolina near a cold front on the morning of November 24 as the main cyclone over the Great Lakes weakened. Rapid development ensued as the surface center began to migrate back into a closed 500 hPa (14.75 inHg)-level (around 6,000 m/20,000 ft above sea level) cyclone, and the cyclone bombed while moving north through Washington, D.C. the next morning. The former occluded front to its northwest became a warm front which moved back to the west around the strengthening, and now dominant, southern low pressure center. By the evening of November 25, the cyclone retrograded, or moved northwestward, into Ohio due to a blocking ridge up across eastern Canada. It was at this time that the pressure gradient was its most intense across southern New England and eastern New York. The cyclone moved west over Lake Erie to the north of the upper cyclone before looping over Ohio as the low-level and mid-level cyclone centers coupled. Significant convection within its comma head led to the development of a warm seclusion, or a pocket of low level warm air, near its center which aided in further development due to the increased lapse rates a warmer low level environment affords under a cold low. After the system became stacked with height, the storm slowly spun down as it drifted north and northeast into eastern Canada over the succeeding few days. [Clarence D. Smith, Jr. [http://docs.lib.noaa.gov/rescue/mwr/078/mwr-078-11-0204.pdf The Destructive Storm of November 25-27, 1950.] Retrieved on 2006-11-25.]

United States effects

This extratropical cyclone rapidly deepened as it moved up the eastern side of the Appalachians during November 24 and November 25 and continued into November 27. Coastal flooding was seen along the U.S. coastline from New Jersey northward.

Alabama

All-time record lows for November were set at Birmingham (5˚F), Mobile (22˚F), and Montgomery (13˚F).

Florida

All-time record lows for November were set at Apalachicola (24˚F), Pensacola (22˚F), and Jacksonville (23˚F).

Georgia

All-time record lows for November were set at Atlanta (3˚F), Augusta (11˚F), and Savannah (15˚F).

Kentucky

An all-time record low for November was set at Louisville (-1˚F).

New Hampshire

Concord record a wind gust of 110 mph (177 km/h) during the height of the storm. Winds at Mount Washington reached 160 mph (257 km/h).

New Jersey

Wind gusts to 108 mph (174 km/h) struck Newark, New Jersey.USA Today. [http://www.usatoday.com/weather/news/1998/wnov1113.htm 'November Witches' Batter Great Lakes.] Retrieved on 2006-11-25.]

New York

Sustained winds of 50-60 mph (80-100 km/h) with gusts to 83 mph were recorded at Albany, New York. A wind gust of 94 mph was recorded in New York City. Extensive damage was caused by the wind across New York, including massive tree fall and power outages. [Old Farmers Almanac. [http://www.almanac.com/newsletter/sample/index.php Weather -- Thanksgiving Storms.] Retrieved on 2006-11-25.] Coastal flooding breached dikes at LaGuardia Airport, flooding the runways. [Richard Monastersky. [http://www.sciencenews.org/pages/sn_arc99/8_28_99/bob1.htm Acclimating to a Warmer World.] Retrieved on 2006-11-26.] Flooding extended to New York City's Office of Emergency Management on the Lower East Side, in Manhattan. [Alexis S. Nussbaum. [http://www.climate.org/topics/weather/new_york_severe_storm_threat.shtml Powerful Hurricanes and Northeasters: Threat to the Big Apple.] Retrieved on 2006-11-26.]

North Carolina

All-time record lows for November were set at Asheville (-5˚F) and Wilmington (16˚F).

Ohio

On the storm's west side, nearly a foot of snow fell on Dayton, Ohio, which combined with the wind and cold temperatures, became their worst blizzard on record. [Weather Channel. [http://www.weather.com/newscenter/specialreports/sotc/storm8/page1.html Storms of the Century: #8 – November 1950 "Appalachian Storm."] Retrieved on 2006-11-25.] Nearly the entire state was blanketed with 10 inches of snow, with 20-30 inches (50-75 cm) being measured in eastern sections of Ohio. The highest report was 44 inches (112 cm) from Steubenville. [Ron Hahn. [http://sheridan.geog.kent.edu/owon/history/nov/november.htm November.] Retrieved on 2006-11-26.] Snow drifts were up to 25 feet (7.6 m) deep. Winds exceeded 40 mph (65 km/h) with gusts as high as 60 mph (96 km/h). Bulldozers were used to clear roads. [Ohio History. [http://www.ohiohistory.org/etcetera/exhibits/swio/pages/content/1950_thanksgivingStorm.htm November 23-27, 1950: Great Thanksgiving Storm.] Retrieved on 2006-11-26.] Despite the high winds and snow, the annual football game between the University of Michigan and Ohio State University went on as scheduled in Columbus and was nicknamed the Snow Bowl. When the snow melted during the first four days of December, river flooding occurred in Cincinnati.

Pennsylvania

During the reign of the storm, record to near-record flooding occurred along the eastern side of the Appalachians across eastern and central sections of the state. The Schuylkill at Fairmont Dam reached its highest stage since 1902. In Pittsburgh, 30.5 inches (77.5 cm) of snow accumulated from this cyclone. Tanks were used to clear the resultant snow. [Remember Pittsburgh. [http://www.rememberpittsburgh.org/3087.html Snow Disaster.] Retrieved on 2006-11-26.] When a warm spell visited the region during the first four days of December, river flooding struck Pittsburgh.

outh Carolina

All-time record lows for November were set at Charleston (17˚F) and Greenville (11˚F).

Tennessee

All-time record lows for November were set at Chattanooga (4˚F), Knoxville (5˚F), Memphis (9˚F), and Nashville (-1˚F).

West Virginia

Parkersburg recorded 34.4 inches (87.3 cm) of snowfall during the passage of this low, which exceeded its snowiest November on record by over 5 inches. Pickens reported the highest amount from anywhere within the cyclone, with 57 inches (145 cm) measured. November 1950 became West Virginia's snowiest month on record. [National Climatic Data Center. [http://lwf.ncdc.noaa.gov/oa/climate/research/2003/feb/st046dv00pcp200302.html Climate of 2003 - February West Virginia Drought.] Retrieved on 2006-11-26.] This remarkably heavy snow led to 160 deaths.

Effects in Canada

Ontario

This system was a major snowstorm for the area, with 12 inches (30.5 cm) in Toronto on November 24. This set a record for single-day snowfall in November. [Weather Doctor. [http://www.islandnet.com/~see/weather/almanac/diarynov.htm Significant Weather Events: Canada.] Retrieved on 2006-11-26.]

Lasting impact

This cyclone was used as a test case for some of the first attempts at numerical modeling of the atmosphere, and is still used as a case study to run recent versions of forecast models. These studies helped create what is now known as the National Centers for Environmental Prediction. [Robert E. Kistler, Louis Uccellini, and Paul J. Kocin. [http://ams.confex.com/ams/84Annual/techprogram/paper_73168.htm Thanksgiving Weekend Storm of 1950.] Retrieved on 2006-11-25.]

Other similar storms

Storms during the time frames November 8-10, 1913, October 22-25, 1923, and November 19-22, 1952 were considered analogous to this cyclone. [Clarence D. Smith, Jr. and Charlotte L. Roe [http://docs.lib.noaa.gov/rescue/mwr/080/text/mwr-080-11-0227.txt COMPARISONS BETWEEN THE STORMS OF NOVEMBER 20-22, 1952, AND NOVEMBER 25-27, 1950.] Retrieved on 2006-11-25.] Despite their similarities, there are some differences. For example, the 1913 event was much more destructive to Great Lakes shipping, while the 1950 storm caused greater snowfall amounts.

ee also

*Cyclogenesis
*Extratropical cyclone
*Great Lakes Storm of 1913

References