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Winter storms routinely damage stands along clearcut boundaries on Northern Vancouver Island, disrupting forest management plans. Empirical modelling of windthrow risk is more suitable than mechanistic modelling for the western hemlock (Tsuga heterophylla (Raf.) Sarg.), redcedar (Thuja plicata (Donn)) and amabilis fir (Abies amabilis Forbes.) stands in this area which vary in composition, structure, density and age. Cutblock edge windthrow in a 900km² study area was mapped using 1:15000 scale aerial photographs. A geographic information system (GIS) database for 3000–50m long by 40m deep cutblock edge segments was assembled using readily available topographic and inventory information. Logistic regression models for predicting probability of damage for various levels of damage severity were evaluated. Key variables in these models included site quality, stocking, boundary orientation, time …