Emergency Management

Definitions
Tropical Depression
- A storm or cluster of storms which is forming a circular pattern with sustained winds less than 39MPH.

Tropical Storm - A tropical depression which has formed a circular pattern and has intensified to between 40MPH and 70MPH. Very heavy thunderstorms and a low pressure area has developed over the center or eye of the storm.

Hurricane - A tropical storm which has intensified to 75MPH and has high tides, strong winds, and heavy rainfall. Their are 5 categories of hurricane intensity: 

  • Category I - 75 to 95 MPH winds; 4 to 5 foot storm surge below eye of storm. Storm surge is the difference between sea level, at the time of the storm, and mean sea level.
  • Category II - 96 to 110 MPH winds; 6 to 8 foot storm surge.
  • Category III - 111 to 130 MPH winds; 9 to 12 foot storm surge.
  • Category IV - 131 to 155 MPH winds; 13 to 18 foot storm surge.
  • Category V - greater than 155 MPH winds and 18 foot storm surge.

Hurricane Watch - A hurricane may threaten an area within 24 hours.

Hurricane Warning - A hurricane is expected to strike an area within 24 hours.

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