An Approach to Forecasting Seasonal Rainfall in Israel

Abstract

In a study of 41 years of rainfall records, it was found that October rainfall amounts correlated well with the following season's total rainfall for Israel. Using mean 500-mb contour charts for the period 1950?1964, a study of the relationship of the mean circulation patterns in October to subsequent 3-month rainfall is presented. It was found that the position and intensity of the mean trough in the Mediterranean, preceding dry, wet and normal seasons, was markedly different for each category. The use of the next upstream trough in the Atlantic as an additional parameter indicates that long waves in October are followed by wet seasons, and short waves by dry seasons. The results obtained for the period studied suggest that these parameters can be used as reliable and objective tools in forecasting winter rains in Israel.