 Surface analysis showing cyclone near time of maximum intensity on November 25, 1950 | |
| Meteorological history | |
|---|---|
| Formed | November 24, 1950[1] |
| Dissipated | November 30, 1950 |
| Category 5 "Extreme" blizzard | |
| Regional snowfall index: 34.69 (NOAA) | |
| Lowest pressure | 978mbar (hPa); 28.88 inHg |
| Maximum snowfall or ice accretion | 57 inches (1,400 mm) |
| Overall effects | |
| Fatalities | 383 |
| Damage | $66.7 million (1950 dollars)[2] |
| Areas affected | Eastern United States Southeast Canada |
TheGreat Appalachian Storm of November 1950 was a largeextratropical cyclone which moved through theEastern United States, causingblizzard conditions along the western slopes of theAppalachian Mountains and significant winds and heavy rainfall east of the mountains. Hurricane-force winds, peaking at 110 miles per hour (180 km/h) inConcord, New Hampshire, and 160 mph (260 km/h) in the highlands ofNew England, disrupted power to 1 million customers during the event.
In all, the storm impacted 22 states, killing 383[3][4][5] people, injuring over 160, and causing$66.7 million in damage (equivalent to $872,000,000 in 2024).[5] U.S. insurance companies paid out more money to their policy holders for damage resulting from the cyclone than for any previous storm or hurricane at the time. The cyclone is also one ofonly twenty-six storms to rank as a Category 5 on theRegional Snowfall Index.[6]
Termed, the "Storm of the Century".[3][5]
The preceding atmospheric state was one ofLa Niña conditions, the cold phase ofENSO, which favors a storm track from theOhio andTennessee Valleys into the Appalachians.[7] Thecyclone initially formed in southeastNorth Carolina near a cold front on the morning of November 24 as the main cyclone over theGreat Lakes weakened.[1] Rapid development ensued as the surface center began to migrate back into a closed 500 hPa-level (14.75 inHg) (around 6,000 m/20,000 ft above sea level) cyclone, and the cyclonebombed 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, intoOhio due to a blocking ridge up across eastern Canada. It was at this time that the pressure gradient was its most intense across southernNew England and eastern New York. A wide area of +4 standard deviation 850mb winds occurred.[8] The cyclone moved west overLake 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 increasedlapse 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.[9]
Thisextratropical cyclone rapidly deepened as it moved up the eastern side of the Appalachians during November 24 and 25 and continued into November 27.Coastal flooding was seen along the U.S. coastline fromNew Jersey northward.
In Alabama, all-time record lows for November were set atBirmingham 5 °F (−15 °C),[10]Mobile 22 °F (−6 °C), andMontgomery 13 °F (−11 °C). Across Florida, all-time record lows for November were set atApalachicola (24 °F (−4 °C)),Pensacola (22 °F (−6 °C)), andJacksonville (23 °F (−5 °C)). Within Georgia, all-time record lows for November were set atAtlanta (3 °F (−16 °C) ),Columbus (10 °F (−12 °C)),Augusta (11 °F (−12 °C)), andSavannah (15 °F (−9 °C).[citation needed]
An all-time record low for November was set atLouisville (−1 °F (−18 °C).[11]
Concord recorded a wind gust of 110 miles per hour (180 km/h) during the height of the storm.[citation needed] Winds atMount Washington reached 160 miles per hour (260 km/h).[12]
Sustained winds of 50–60 mph (80–97 km/h) with gusts to 83 miles per hour (134 km/h) were recorded atAlbany, New York. A wind gust of 94 miles per hour (151 km/h) was recorded in New York City. Extensive damage was caused by the wind across New York, including massive tree fall and power outages.[13] Coastal flooding breached dikes atLaGuardia Airport, flooding the runways.[14] Flooding extended to New York City's Office of Emergency Management on theLower East Side, inManhattan.[15]
Extensive wind damage with tidal flooding along the coast. On the coast structures and railroad tracks washed away. Plows were needed to remove sand from coastal roads. Roofs torn off on the coast and at the University of Connecticut. The tide atNew London was 7.58 ft (2.31 m), third highest in the last 100 years.Hartford had sustained winds of 70 mph (110 km/h), the highest ever on record, with 100 mph (160 km/h) gusts also the highest on record were recorded on 3 separate occasions. The 62 mph (100 km/h) sustained wind recorded atBridgeport is the 4th highest on record. Other gusts included 88 mph (142 km/h) at Bridgeport and 77 mph (124 km/h) atNew Haven.[8]
A wind gust of 108 mph (174 km/h), the strongest ever recorded in New Jersey, occurred inNewark.[16]
All-time record lows for November were set atAsheville 1 °F (−17 °C)[17] andWilmington 16 °F (−9 °C).[citation needed]
On the storm's west side, nearly a foot of snow fell onDayton, Ohio, which combined with the wind and cold temperatures to constitute their worst blizzard on record.[18] Nearly the entire state was blanketed with 10 inches (25 cm) of snow, with 20–30 inches (51–76 centimetres) being measured in eastern sections of Ohio. The highest report was 44 inches (110 cm) fromSteubenville.[19] Snow drifts were up to 25 feet (7.6 m) deep. Winds exceeded 40 miles per hour (64 km/h) with gusts as high as 60 miles per hour (97 km/h). Bulldozers were used to clear roads.[1] Despite the high winds and snow, the annualfootball game between theUniversity of Michigan andOhio State University went on as scheduled inColumbus and was nicknamed theSnow Bowl. When the snow melted during the first four days of December, river flooding occurred inCincinnati.[citation needed]
During the height of the storm, record to near-record flooding occurred along the eastern side of the Appalachians across eastern and central sections of the state. TheSchuylkill at Fairmount Dam reached its highest stage since 1902.[2] InPittsburgh, 30.5 inches (77 cm) of snow accumulated from this cyclone. Tanks were used to clear the resultant snow.[20] When a warm spell visited the region during the first four days of December, river flooding struck Pittsburgh.
All-time record lows for November were set atCharleston (17 °F (−8 °C)) andGreenville (11 °F (−12 °C)).[citation needed]
All-time record lows for November were set atChattanooga (4 °F (−16 °C)),[citation needed]Knoxville (5 °F (−15 °C)),[21]Memphis (9 °F (−13 °C)), andNashville (−1 °F (−18 °C)).[citation needed]
Parkersburg recorded 34.4 inches (87 cm) of snowfall during the passage of this low, which exceeded its snowiest November on record by over 5 inches (13 cm).Pickens reported the highest amount from anywhere within the cyclone, with 57 inches (140 cm) measured. November 1950 becameWest Virginia's snowiest month on record.[22] This remarkably heavy snow led to 160 deaths.[23]
This system was a major snowstorm for the area, with 12 inches (30 cm) inToronto on November 24. This set a record for single-day snowfall in November.[24]
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 theNational Centers for Environmental Prediction.[25]
Storms during the time framesNovember 8–10, 1913, October 22–25, 1923, and November 19–22, 1952 were considered analogous to this cyclone.[26] Despite their similarities, there are some differences. For example, the 1913 event was much more destructive toGreat Lakes shipping, while the 1950 storm caused greater snowfall amounts.
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