This study examines the influences of fuel, weather and topography on lightning-caused forest fires in portions of southern British Columbia and Alberta, Canada. The results show a significant difference in lightning and lightning-caused fires east and west of the Continental Divide. In British Columbia, on average there was one fire for every 50 lightning discharges whereas in Alberta there was one fire for every 1400 lightning discharges. Elevation, the distribution of lightning strikes, the Daily Severity Rating (a component of the Canadian Forest Fire Weather Index System) and vegetation composition were identified as primary agents controlling lightning fire occurrence. However, the multivariate analysis does suggest that there are other factors influencing fire occurrence other than the biophysical factors we tested. The implications of the lightning and lightning-ignited fires for land managers are discussed.