Hurricane Categorization

Be aware of National Hurricane Center advisories and bulletins and local official advisories. As weather conditions develop, you should be aware of terms being used:

• Tropical Wave or Disturbance: A cluster of clouds and/or thunderstorms without an organized circulation, moving through the tropics. Stronger systems start as Tropical Waves.
  
• Tropical Depression: An organized system of clouds and thunderstorms with a defined circulation and top winds of less than 39 mph.
  
• Tropical Storm: An organized system of strong thunderstorms with defined circulation and top winds of 39 - 74 mph, which can quickly develop into hurricanes.
  
• Tropical Storm Watch: Tropical storm conditions are possible in the specified area of the watch, usually within 36 hours.
  
• Hurricane: An intense tropical weather system with a well-defined circulation and a sustained wind speed of 74 mph or higher.
  
• Hurricane Watch: A hurricane watch covers a specified area and duration and means that hurricane conditions are a real possibility. When a hurricane watch is issued, listen for further advisories, take steps to notify your employees, secure your office, and be prepared to evacuate if necessary. Hurricane conditions are possible in the specified area of the Watch, usually within 36 hours. During a Hurricane Watch, prepare to take immediate action to protect your property in case a Hurricane Warning is issued.
  
• Hurricane Warning: When conditions are expected within 24 hours, a hurricane warning will be announced by the National Hurricane Center. All precautionary measures should be completed and you may be required to evacuate the building.