Hurricane Andrew in Florida: Dynamics of a Disaster

Abstract

Four meteorological factors aggravated the devastation when Hurricane Andrew struck South Florida: completed replacement of the original eyewall by an outer, concentric eyewall while Andrew was still at sea; storm translation so fast that the eye crossed the populated coastline before the influence of land could weaken it appreciably, extreme wind speed, 82 m s?1 winds measured by aircraft flying at 2.5 km; and formation of an intense, but nontornadic, convective vortex in the eyewall at the time of landfall. Although Andrew weakened for 12 h during the eyewall replacement, it contained vigorous convection and was reintensifying rapidly as it passed onshore. The Gulf Stream just offshore was warm enough to support a sea level pressure 20?30 hPa lower than the 922 hPa attained, but Andrew bit land before it could reach this potential. The difficult-to-predict mesoscale and vortex-scale phenomena determined the course of events on that windy morning, not a long-term trend toward worse hurricanes.