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Tornado and Hurricane

A hurricane is a tropical weather system with sustained winds of 74 mph or higher and well-defined circulation that can produce tornadoes, storm surge, heavy rain, flooding, and landslides.

A tropical storm is a system of strong thunderstorms with maximum sustained winds of 39 to 73 mph and a defined circulation.

A tropical depression is the same but with winds less than 38 mph.
Typhoon - A hurricane in the western Pacific
Cyclone - A hurricane in the Indian Ocean

A tornado is a circular wind pattern with wind speeds up to 300 mph, a width of between 100 and 300 yards, and forward speeds up to 60 mph.

The relatively calm eye of a hurricane is generally 20 to 30 miles wide, and the storm can extend outward as much as 400 miles. The heaviest rain and tornadoes are often in the right front quadrant of the storm, usually within 12 to 24 hours of landfall. Powered by heat from the ocean, a hurricane sweeps ocean water ashore in the form of a storm surge. The surge is a dome of water 15 to 20 miles wide and 4 to 20 feet high that is responsible for about 90 percent of hurricane fatalities. Tornadoes account for most of the rest.

Atlantic Ocean storms produce more tornadoes than Gulf of Mexico storms, usually within 30 miles of the eye or in the outer bands 100 to 150 miles from the storm's center. Most tornadoes occur within 150 miles of the coast, often in the daytime. Interaction with a cold front produces more rain and tornadoes. Rainfall of 10 to 15 inches is common during hurricane landfall. Peak hurricane threat in the U.S. is from mid-August to late October, but hurricanes can develop as early as June or into late November.

As winds increase, the pressure against buildings mounts disproportionately. A 25-mph wind produces pressure of 50 pounds on a 4x8 sheet of plywood. In 75-mph wind that pressure increases to 450 pounds and in 125-mph wind, the pressure is 1,250 pounds.

A hurricane watch indicates a threat of hurricane conditions within 24 to 36 hours, while a hurricane warning means such conditions can occur in less than 24 hours. If authorities order an evacuation, secure your home by shutting off gas, electricity, and water.