Forecasting the Lake Breeze and Its Effects on Visibility at Chicago Midway Airport *

Abstract

As a bearer of smoke the lake breeze creates a problem in forecasting visibility. A study of three summers totaling thirty-three occurrences suggests a number of criteria for judging the probability of the lake breeze, time of occurrence, and density of smoke. These include the necessity for nearly clear sky, light winds with a preference shown for northerly winds, and a surface pressure pattern of relatively high pressure. A suggested forecast procedure is included.