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Johnstown Flood
after the catastrophic failure of the South Fork Dam on the Little Conemaugh River 14 miles (23 km) upstream of the town of Johnstown, Pennsylvania. The dam broke after several days of extremely heavy rainfall, unleashing 20 million tons of water (18 million cubic meters) from the reservoir known as Lake Conemaugh. -
Great Hinckley Fire
After a two-month summer drought, combined with very high temperatures, several small fires started in the pine forests of Pine County, Minnesota. The fires' spread apparently was due to the then-common method of lumber harvesting, wherein trees were stripped of their branches in place; these branches littered the ground with flammable debris. -
Okeechobee Hurricane
was one of the deadliest tropical cyclones in the history of Puerto Rico. The fourth tropical cyclone, third hurricane, and only major hurricane of the 1928 season, this system developed just offshore the west coast of Africa on September 6. Initially a tropical depression, it strengthened into a tropical storm later that day, shortly before passing south of the Cape Verde Islands. -
Super Outbreak
The entire outbreak caused more than $600 million (1974 USD) in damage in the United States alone, and extensively damaged approximately 900 sq mi (2,331 km2) along a total combined path length of 2,600 mi (4,184 km).[1][2] At one point, as many as 15 separate tornadoes were ongoing at the same time. -
Great Lakes Blizzard
Daily peak wind gusts ranging from 46 to 69 mph (74 to 111 km/h) were recorded by the National Weather Service in Buffalo with snowfall as high as 100 in (254 cm) recorded in areas,[1] and the high winds blew this into drifts of 30 to 40 ft (9 to 12 m). There were 23 total storm-related deaths in western New York, with five more in northern New York. -
The North American Drought
This multi-year drought began in most areas in 1988 and continued into 1989. The drought caused $60 billion (1988 United States dollars) in damage ($120 billion in 2014 United States dollars, adjusting for inflation). The drought occasioned some of the worst blowing-dust events since 1977 or the 1930s in many locations in the Midwestern United States, including a protracted dust storm, which closed schools in South Dakota in late February 1988. -
Great Flood of the 1993
April to October 1993. The flood was among the most costly and devastating to ever occur in the United States, with $15 billion in damages. The hydrographic basin affected cover around 745 miles (1,199 km) in length and 435 miles (700 km) in width, totaling about 320,000 square miles (830,000 km2).[2] Within this zone, the flooded area totaled around 30,000 square miles (78,000 km2)[3] and was the worst such U.S. disaster since the Great Mississippi Flood of 1927, -
Northridge Earthquake
It had a duration of approximately 10–20 seconds. The blind thrust earthquake had a moment magnitude (Mw) of 6.7, which produced ground acceleration that was the highest ever instrumentally recorded in an urban area in North America,[5] measuring 1.8g (16.7 m/s2)[6] with strong ground motion felt as far away as Las Vegas, Nevada, about 220 miles (360 km) from the epicenter. The peak ground velocity at the Rinaldi Receiving Station was 183.