Wind Field Simulation and Wind Damage Assessment of Typhoon Rai in the Philippines

Typhoon Rai (Local Name: Odette) was regarded as the strongest typhoon to have struck the Southern Philippines in the last 31 years. It is also the first violent typhoon classified by the new classifications by the Japan Meteorological Agency. A forensic meteorological analysis was performed to extrapolate the surface winds and 10-min sustained winds experienced by the affected areas using the gradient wind equation. Gradient winds are determined to be closer to the surface winds during land interaction because of dissipation in the pressure field. Wind exposure plays a major factor in how the winds amplify or decrease over different exposure categories. A subsequent wind damage assessment is performed in the Cebu Province to relate the documented building damages to the winds determined by the wind field simulation, which identified 73% of building damage outliers for concrete structures and 87% of building damage outliers for steel structures.