Based on common weather conditions, novel methods are disclosed for the prediction of electrical power distribution interruptions and for interruption risk assessment based on immediate weather conditions. Daily, hourly, and bi-hourly weather data are used to predict the number of interruptions and to normalize reliability indices for weather. Common weather conditions include, but are not limited to, rain, wind, temperature, lightning, humidity, barometric pressure, snow, and ice. These conditions do not occur simultaneously at any one place, and the range of combinations is great, therefore the invention allows broad application of the disclosed methods.