Wind characteristics of tropical thunderstorms

Measurements obtained from a wind and rain monitoring stations set-up in Singapore, a place with frequent tropical thunderstorms, are reported. Wind speeds and wind directions at five levels on a 20 m mast are continuously recorded with the simultaneous monitoring of rainfall intensity. Most of the higher gust speeds are observed to occur during tropical thunderstorms, which suggests that thunderstorm wind is a major factor defining the wind loading design criteria in places like Singapore. General wind and rain patterns during the passage of a thunderstorm are described in the paper. The gust front and its configuration are reported. Velocity profiles, turbulence intensities and gust factors during thunderstorms are compared with those for other wind conditions (non-thunderstorm). It is observed that the gust factors and turbulence intensities during thunderstorms are much higher than those of the non-thunderstorm winds over the same terrain.