Hurricane 101

What Is A Hurricane?

A hurricane is defined as a low-pressure system that generally forms in the tropics. The system is accompanied by thunderstorms and, in the Northern atmosphere, a counter-clockwise circulation of winds near the earth's surface. Tropical systems are classified as follows:

  • Tropical Depression - An organized system with a defined surface circulation and maximum sustained winds of 38 MPH.
  • Tropical Storm - An organized system with a defined surface circulation and maximum sustained winds of 39-73 MPH.
  • Hurricane - An intense tropical weather system with a well-defined surface circulation and maximum sustained winds of 74 MPH or higher.

Hazards associated with hurricanes include, flooding, high winds and storm surge which occurs when water is pushed towards the shore by strong hurricane winds.

Saffir-Simpson Hurricane Scale

Storm Category Wind SpeedDamage
174-95 MPHMinor building damage. Damage primarily to unanchored mobile homes, shrubbery and trees. Some coastal road flooding and minor pier damage.
296-110 MPHSome roofing material, door and window damage to buildings; considerable damage to vegetation, mobile homes and piers.
3111-130 MPH                            Some structural damage to small residences and utility buildings. Mobile homes are destroyed. Flooding near the coast destroys smaller structures with larger structures damaged by floating debris.
4131-155 MPHMore extensive damage with some complete roof structure failure. Extensive flooding probable requiring massive evacuation of residential areas.
5155 MPH and higherExtensive complete roof failure and some building failure. Major damage to structures located less than 15 feet above sea level and within 500 yards of shoreline. Massive evacuation of residential areas on low ground within five to ten miles of the shoreline may be required.

Watch Vs. Warning

  • Hurricane Watch:  hurricane conditions are expected within 36 hours. Residents are urged to enact their disaster plans and secure their homes.
  • Hurricane Warning:  hurricane conditions may be experienced within 24 hours. Residents are urged to finalize disaster action plans and seek shelter in a safe location.

Watch the video below for information about what to do when a watch has been issued and when a warning has been issued.

What To Do During A Hurricane Watch And A Hurricane Warning