The Probability of Record Daily Low Temperatures in Winter

Abstract

Probabilities of setting record daily low temperatures during the winter half-year were determined empirically for selected stations in the upper Midwest. The probability of a new record low depends upon the length of station observational record, decreasing as record length increases. Thus, the probability of five or more record low daily temperatures during the winter period is about 0.5 for stations with 35 years of observations, and 0.1 at stations with 100 years of data. Frequency of occurrence of new record low daily temperatures is, therefore, an appropriate measure of the severity of a winter only if those frequencies are related to the length of the observational record at a particular station.