PAR Disaster Services Inc. - Hurricane Classification, Saffir-Simpson Hurricane Scale, Surveillance and Forecasting, Personal and Community Preparedness, Family Disaster Plan

Surveillance and Forecasting

Satellite
Geostationary satellites orbiting the earth at an altitude of about 22,000 miles above the equator provide imagery both day and night. The satellite imagery helps provide estimates of the location, size, and intensity of a storm and its surrounding environment.

Reconnaissance Aircraft
The US Air Force Reserve provides most of the operational reconnaissance. Pilots fly aircraft into the core of a hurricane to measure wind, pressure, temperature, and humidity as well as to provide an accurate location of the center of the hurricane. The National Oceanic and Atmospheric Administration also flies aircraft into hurricanes to aid scientists in better understanding these storms and to improve forecast capabilities. The NOAA flights also provide operational support as required.

Radar
When a hurricane gets close to the coast, it is monitored by land-based weather radars. The National Weather Service is currently installing Doppler weather radars across the country which will add new dimensions to hurricane warning capabilities. They will provide detailed information on hurricane wind fields and their changes. Local NWS offices will be able to provide more accurate short-term warnings for floods, tornadoes, and inland high winds.

National Hurricane Center Models
The National Hurricane Center uses several different numerical computer models to aid in forecasting the path, speed, and strength of hurricanes. Data from weather satellite sensors, reconnaissance aircraft, and other sources are fed into these computer models. The National Hurricane Center also has a computer storm surge model. This model provides guidance on storm surge height and the extent of flooding it will cause.

What To Listen For...

NOAA Weather Radio is the best means to receive warnings from the National Weather Service

The National Weather Service continuously broadcasts updated hurricane advisories that can be received by NOAA Weather Radios sold in many stores. The average range is 40 miles, depending on topography. Your National Weather Service recommends purchasing a radio that has both a battery backup and a tone-alert feature which automatically alerts you when a watch or warning is issued.

TROPICAL STORM WATCH: Tropical Storm conditions are possible in the specified area of the Watch, usually within 36 hours.
TROPICAL STORM WARNING: Tropical Storm conditions are expected in the specified area of the Warning, usually within 24 hours.
HURRICANE WATCH: 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 family and property in case a Hurricane Warning is issued.
HURRICANE WARNING: Hurricane conditions are expected in the specified area of the Warning, usually within 24 hours. Complete all storm preparations and evacuate if directed by local officials.
SHORT TERM WATCHES AND WARNINGS: These provide detailed information on specific hurricane threats, such as tornadoes, floods, and high winds.

Information for Local Decision Makers

The PUBLIC ADVISORY - issued by the National Hurricane Center provides critical hurricane warning and forecast information.
The MARINE ADVISORY - issued by the National Hurricane Center provides detailed hurricane track and wind field information.
The TROPICAL CYCLONE UPDATE - issued by the National Hurricane Center highlights significant changes in a hurricane that occur between advisories.
PROBABILITIES OF HURRICANE/TROPICAL STORM CONDITIONS - provide a measure of the forecast track accuracy. The probabilities have no relation to tropical cyclone intensity.
HURRICANE LOCAL STATEMENTS - issued by local National Weather Service offices give greater detail on how the storm will impact your area.

All of the above information must be used to make an informed decision on your risk and what actions should be taken. Remember to listen to your local official's recommendations and to NOAA Weather Radio for the latest hurricane information.