A History of Hurricanes in the US

A History of Hurricanes in the US THE CLASSIFICATIONS TROPICAL DEPRESSIONS TROPICAL CYCLONES TROPICAL STORMS HURRICANES CYCLONES TYPHOONS Of the 100 or so tropical storms which form each year, two-thirds develop into hurricanes, cyclones or typhoons * MORE INTENSE STORMS Pacific Ocean TYPHOONS HURRICANES CYCLONES CYCLONES Atlantic Ocean Pacific Ocean Indian Ocean HOW A HURRICANE IS FORMED A hurricane is made of bands of thunderstorms that spiral around the center The surrounding clouds may have a diameter of 300 miles and reach a height of six miles Laver of warm sea water must be at least 27°C and 60m deep Latent heat warms surrounding air air becomes lighter and rises 2 Winds must be converging near the surface Existing wind at all altitudes must be the same speed and direction Air rises. More air flows in to replace it, causing wind High pressure area in upper atmosphere pumps away air rising in the storm Water vapour in rising air condenses into droplets, releasing latent heat AT SEA UPON LANDFALL EFFECTS ON EARTH Shipping Strong winds Storm surge Heavy rainfall Tornadoes Large waves, heavy rain, and high winds, disrupt international shipping and, at times, cause shipwrecks. Strong winds can damage or destroy vehicles, buildings, bridges, and other outside objects. Winds in a hurricane can reach up to 200 mph. The quick surge in sea level can move miles/km inland, flooding homes and cutting off escape routes. It's responsible for 90% of all hurricane Intense rainfall can potentially result in flooding, mudslides, and landslides. Inland areas are particularly vulnerable to flooding, due to residents not preparing adequately. The broad rotation of a landfalling tropical cyclone often spawns tornadoes. Most tornadoes that occur in hurricanes are only minimal in strength. related deaths. U.S. HURRICANE STRIKES BY DECADE Number of hurricanes by Saffir-Simpson Category to strike the mainland U.S. each decade CATEGORY 1851-1860 1 MINIMAL 2001-2004 2 MODERATE 000. 00000 3 EXTENSIVE 00000 4 EXTREME 5 CATASTROPHIC SAFFIR-SIMPSON CATEGORY Storm Surge (Ft) 9 13 18+ 980+ 979 964 944 <920 Pressure (Mbars) • 0000 000 0000 000 1911-1920 1941-1950 1921-1930 1931-1940 2000-2007 STORMS Hurricane season storms by month of formation (excludes subtropical storms) Hurricane season runs from June 1 to November 30 September is the statistical height of each hurricane season Tropical storm ●Hurricane June November July October August September LIST OF DEADLIEST ATLANTIC HURRICANES Number of deaths 1780 Great Hurricane of 1780 27,500+ 1998 Mitch 11,374 – 18,000 1900 Galveston 8,000 – 12,000 1974 1930 1963 Fifi Dominican Republic Flora 8,000 – 10,000 2,000 – 8,000 7,186 – 8,000 1881-1890 1871-1880 1891-1900 0000. 000 0000. 00000 1901-1910 1861-1870 00000 0000 00000 0000 ●●●●● 0000 000 Damage Level cat. extr. exte, mod, mi 96 111 131 156+ Wind Speed (Mph) 0000 000 00000 0000 0000 00000 1951-1960 1991-2000 1961-1970 1981-1990 1971-1980