What is a Hurricane?

A hurricane satellite image

A hurricane is a type of tropical cyclone, which is a generic term for a low-pressure system that generally forms in the tropics. The cyclone is accompanied by thunderstorms and, in the Northern Hemisphere, a counterclockwise circulation of winds near the earth's surface. The Atlantic Hurricane Season runs from June 1 to November 30.

Tropical cyclone classifications

  • Tropical Depression: A tropical cyclone with maximum sustained winds of 38 mph or less.
  • Tropical Storm: A tropical cyclone with maximum sustained winds of 39 to 73 mph.
  • Hurricane: A tropical cyclone with maximum sustained winds of 74 mph or higher.

Storm Naming

Categories

Hurricanes are categorized according to the strength of their winds using the 1 to 5 rating on the Saffir-Simpson Hurricane Scale. This scale does not take into account other potentially deadly hazards such as storm surge, rainfall, flooding, and tornadoes. Source: National Weather Service

Very dangerous winds will produce some damage: Well-constructed frame homes could have damage to roofs, shingles, vinyl siding and gutters. Large branches of trees will snap and shallowly rooted trees may be toppled. Extensive damage to power lines and poles will likely result in power outages that could last a few to several days.

Extremely dangerous winds will cause extensive damage: Well-constructed frame homes could sustain major roof and siding damage. Many shallowly rooted trees will be snapped or uprooted and block numerous roads. Near-total power loss is expected with outages that could last from several days to weeks.

Devastating damage will occur: Well-built framed homes may incur major damage or removal of roof decking and gable ends. Many trees will be snapped or uprooted, blocking numerous roads. Electricity and water will be unavailable for several days to weeks after the storm passes.

Catastrophic damage will occur: Well-built framed homes can sustain severe damage with loss of most of the roof structure and/or some exterior walls. Most trees will be snapped or uprooted and power poles downed. Fallen trees and power poles will isolate residential areas. Power outages will last weeks to possibly months. Most of the area will be uninhabitable for weeks or months.

Catastrophic damage will occur: A high percentage of framed homes will be destroyed, with total roof failure and wall collapse. Fallen trees and power poles will isolate residential areas. Power outages will last for weeks to possibly months. Most of the area will be uninhabitable for weeks or months.

Non-Hurricane Classifications

  • Tropical Depression: Winds less than 38 MPH.

  • Tropical Storm: Winds between 39-73 MPH.

Watches & Warnings

The National Hurricane Center uses watches and warnings to inform the public of possible impacts from a storm. Familiarize yourself with the terms used to identify a tropical weather threat. Source: National Weather Service

A Tropical Storm Watch is issued when Tropical Storm conditions, including winds of 39-73 mph, pose a possible threat to a specified coastal area within 48 hours.

A Tropical Storm Warning is issued when Tropical Storm conditions, including winds of 39-73 mph, are expected in a specified coastal area within 36 hours or less.

A Hurricane Watch is issued when sustained winds of 74 mph or higher are possible within the specified area of the Watch. Because hurricane preparedness activities become difficult once winds reach tropical storm force, the Watch is issued 48 hours in advance of the onset of tropical storm force winds.

A Hurricane Warning is issued when sustained winds of 74 mph or higher are expected somewhere within the specified area of the Warning. Because hurricane preparedness activities become difficult once winds reach tropical storm force, the Warning is issued 36 hours in advance of the onset of tropical storm-force winds.

A Storm Surge Watch is issued when there is a possibility of life-threatening inundation from rising water moving inland from the shoreline. This is typically expected to occur within 48 hours in association with an ongoing or potential tropical cyclone, a subtropical cyclone, or a post-tropical cyclone.

A Storm Surge Warning is issued when there is a danger of life-threatening inundation from rising water moving inland from the shoreline. This is typically expected to occur within 36 hours in association with an ongoing or potential tropical cyclone, a subtropical cyclone, or a post-tropical cyclone.

Tracking

Hurricane Websites

Historical Hurricane Tracks: View NOAA's new Historical Hurricane Tracks website. Type in your ZIP code and see how many storms have moved through your area in any given year going back to 1851.

National Hurricane Center: This is the official website for the National Hurricane Center located in South Florida.

National Hurricane Center RSS Feeds: Subscribe to the National Hurricane Center's Really Simple Syndication (RSS) feeds for the latest storm updates in a headline or news digest format.

National Weather Service: Enter your city and state for a comprehensive, customized look at the weather in your area, including current conditions, a 7-day forecast, hazardous weather information, radar and satellite images and access to National Weather Service chats and discussions.

NOAA Weather Radio: This website provides information regarding NOAA's Weather Radio nationwide network.

NOAA Atlantic 2-Day Graphical Tropical Weather Outlook Map