The Hurricane Rainband and Intensity Change Experiment

In tropical cyclones maximum wind speed of the storm, which occurs at the eyewall, is a primary indicator of its overall strength which is important in predicting overall intensity.

RAINEX’s main purpose was to accomplish this task via studying the fluctuations of storm intensity as they are influenced by interactions between the eye, eyewalls, and rainbands of a tropical cyclone.

Previously, tropical cyclone intensity forecasting was heavily based on sea surface temperature and upper-atmosphere dynamics.

These spiral rain bands were known to be complex structures that possess deep convective cores enmeshed in low altitude precipitative clouds.

[2] The eye or core of a tropical cyclone is characterized by low pressure which causes warm air to spiral upward and rise into the atmosphere.

A tropical cyclone usually develops a distinct eye when the maximum sustained winds of the storm reach and exceed 74 mph.

A well-formed eye is a good indicator of overall intensity due to an increase in rotational velocity when the distance between the moving particles and the center of the vortex is decreased.

The experiment entailed a high-resolution numerical model of the internal structure of the vortex and collection of data by three P3 Orion aircraft equipped with dual beam Electra Doppler weather radar and intensive dropsonde coverage.

[3] All flights were controlled from the RAINEX operations center (ROC) at the Rosenstiel School of Marine, Atmospheric, and Earth Science (RSMAS) at the University of Miami.

In order to determine which days were suitable for flight, principal investigators, forecasters, pilots, and facility engineering staff held a daily conference call originating from the RSMAS center in Miami, Florida.

Hurricane Ophelia was an interesting storm to document due to its long duration and considerable fluctuations in strength throughout its existence.