When does a tropical storm become a hurricane?

Did you know that a tropical storm becomes a hurricane when winds reach 74 miles per hour? This is peak hurricane season.

A hurricane is a severe tropical storm that forms in the North Atlantic Ocean, the Northeast Pacific Ocean or the South Pacific Ocean. Hurricanes need warm tropical oceans, moisture, and light winds above them. If the right conditions last long enough, a hurricane can produce violent winds, large waves, torrential rains, and floods.

Hurricanes rotate in a counterclockwise direction around an "eye." A tropical storm becomes a hurricane when winds reach 74 miles per hour (mph). The Saffir-Simpson Hurricane Wind Scale then rates the hurricane between one and five based on its wind speed.

The Atlantic hurricane season begins June 1 and ends November 30, with peak activity occurring August through October. There are, on average, six Atlantic hurricanes each year. The East Pacific hurricane season runs from May 15 through November 30, with peak activity occurring July through September. In a normal season, the East Pacific would expect nine hurricanes.

Please note: If you have survived a disaster, such as a major hurricane, you may be eligible for federal assistance. If your county has been issued a disaster declaration, you may apply for assistance with FEMA. For more information, or to apply over the phone, please call 1.800.621.FEMA (1.800.621.3362).

Additional Resources:

• How to Prepare for a Hurricane
• What to Do during a Hurricane Watch 
• What to Do during a Hurricane Warning 
• What to Do after a Hurricane
• The National Hurricane Center's (NHC) Hurricane Awareness web page - provides hurricane warnings and forecasts.
• The NHC's List of Frequently Asked Hurricane Questions
• The Federal Emergency Management Agency's (FEMA) Hurricane Information 
• FEMA's Are You Ready? Hurricanes web page
• USA.gov's Hurricanes web page
• The Centers for Disease Control and Prevention's (CDC) Hurricanes, Cyclones, Typhoons and Tropical Storms web page
• The Environmental Protection Agency's (EPA) Hurricanes web page
• Hurricane Breakpoints - locations referred to when advisories are issued for coastal and offshore areas.
• National Hurricane Preparedness Week - took place May 23 through 29, 2010.
• Presidential Proclamation - National Hurricane Preparedness Week

by usa.gov team