Terms to know
- Tropical depression - A tropical cyclone in which the maximum sustained surface wind is 38 mph or less.
- Tropical storm - A tropical cyclone in which the maximum sustained surface wind is 39-73 mph.
- Hurricane Watch - An announcement for an area that a hurricane or hurricane conditions may pose a threat to coastal areas within 36 hours.
- Hurricane warning - A warning that sustained winds of 74 mph or higher associated with a hurricane is expected within 24 hours or less.
Costliest hurricanes
Hurricanes leave havoc in their wake. The 10 costliest to hit the U.S. mainland:
- Katrina - Alabama, Mississippi, Louisiana, 2005, $75 billion
- Andrew - Florida and Louisiana, 1992, $35 billion.
- Hugo - South Carolina, 1989, $7 billion.
- Floyd - Mid-Atlantic and Northeast, 1999, $4.5 billion.
- Fran - North Carolina, 1996, $3.2 billion.
- Opal - Florida and Alabama, 1995, $3 billion.
- Georges - Florida Keys, Mississippi and Alabama, 1998, $2.31 billion.
- Frederic - Alabama and Mississippi, 1979, $2.3 billion.
- Agnes - Florida, Northeast U.S., 1972, $2.1 billion.
- Alicia - Texas, 1983, $2 billion.
Deadliest hurricanes
Galveston, Texas, 1900, 8,000 to 12,000 dead.
Lake Okeechobee, Fla., 1928, 1,836.
Alabama, Mississippi, Louisiana, 2005, 1,605 (Katrina)
Florida Keys and South Texas, 1919, more than 600 to 900.
New England, 1938, 600.
Florida Keys, 1935, 408.
Southwest Louisiana and North Texas, 1957, 390 (Audrey)
Northeast U.S., 1944, 390.
Grand Isle, La., 1909, 350.
New Orleans, 1915, 275.
Galveston, Texas, 1915, 275.