Abstract
　By a stochastic model, the future course and central pressure of a typhoon are simulated as a function of the motion and the change in central pressure depth. Ap, for the past six hours. The gradient wind is computed as a wind balancing to the simulated pressure pattern, and then the sea-surface wind is estimated. As a case study occurrence probabilities of severe wind for Typhoon 9019 (FLO) are predicted for the period when it was approaching to the Japanese Main Islands. At the coast line of the Kii Peninsula, occurrence probability is 25% on three days before landfall, but it increases to 60% on two days before landfall. This model can be used in estimation of tidal waves and a design wind for huge buildings and structures, and it can be also applied to an economical planning in disaster prevention works.

【キーワード】：台風，強風出現率，シミュレーション，傾度風速，台風９０１９号
Key words: typhoon, occurrence probability of severe wind, simulation, gradient wind, sea-surface wind, Typhoon 9019 (FLO)

*京都産業大学教養部
College of General Liberal Arts and Science Education, Kyoto Sangyo University
**京都大学防災研究所
Disaster Prevention Research Institute, Kyoto University