Meteorological Analysis of an Oahu Flood

Abstract

A detailed study has been made of the severe Oahu rainstorm 19 April 1974 and its implications for the Hawaii flood forecast problem. Data from Qahu's extensive recording raingage network were analyzed to determine the mesoscale structure of the precipitating cloud systems. Study of a special rain and stream gage network in Moanalua Valley showed that the current Hawaiian detection scheme based on one telemetered raingage per watershed is inadequate. Raingage data were incorporated with available conventional meteorological observations to construct a conceptual model of the flood-producing convective regime of 19 April. It was concluded that orography played an essential role in the persistence of major thunderstorm activity.