Warm season extreme temperature events in Kuwait

The incidence of heat waves, hot days, very hot days and extremely hot days in Kuwait during the warm seasons (May-August) from 1958 to 2000 was investigated. First, we examined a circulation pattern that causes these phenomena by analyzing the most significant events. Second, we provided a statistical analysis of their incidence including an analysis of their duration and temporal variability. The investigation of temperature data and synoptic maps shows that extremely high temperatures in the warm season are due to the changes in the regional circulation pattern. Along with typical summer conditions that effect Kuwait and the northern region of the Arabian Gulf, the shift of the Subtropical Jet Stream northward and the build up of the ridge of high pressure in the 500 hPa level play a major role in heat wave events during the summer season in Kuwait. The hot and dry Arabian Peninsula air masses are transferred to the region and the process is intensified by subsidence of air. The most significant heat wave events, as far as both their duration and intensity are concerned occurred in the last decade of the 20th century. During such episodes the daily maximum temperature significantly exceeded the 1961-1990 average for several days and local temperature extremes were observed. (C) 2003 Elsevier Ltd. All rights reserved.