SOME UNUSUAL ASPECTS CONCERNING THE DEVELOPMENT AND STRUCTURE OF TYPHOON BILLIE—JULY 1967

Abstract

Typhoon Billie exhibited mesoscale warm-core characteristics and developed winds of typhoon intensity without ever forming a wall cloud around the eye. Clouds that swirled into the storm center were flattened cumulus and stratocumulus with cloud tops at 4,000 to 5,000 ft. It was clear of all higher cloudiness in the area of the eye. The storm center lay on the northern edge of major overcast cloudiness and its appearance was similar to that of an intense Stage C tropical cyclone. Satellite pictures together with conventional analyses and information gathered by the author as a pilot on reconnaissance missions into the storm indicate that Billie intensified to typhoon strength as a result of mesoscale changes in the area of the eye. It is suggested that Billie represents a type of typhoon whose maximum wind speeds are limited because of failure to develop an encircling wall cloud.