The spatial and temporal characteristics of dust storms in the Middle East were studied by an analysis of the visibility reduction in that region. Eight ‘three-hours’ mean values for each month for a period of 21 years (1973–1993) were used. Data were subjected to cluster analysis of their temporal behaviour. Four main regions were identified and mapped. Stations within each cluster (region) have a similar temporal behaviour different from the behaviour of stations out of that cluster. Sudan, Iraq, Saudi Arabia and the Persian Gulf, are the regions that reported the greatest occurrence of dust storms. Dust storms in Iran, north-eastern Iraq and Syria, the Persian Gulf and southern Arabian Peninsula are more frequent in summer. In western Iraq and Syria, Jordan, Lebanon, northern Israel, northern Arabian Peninsula and southern Egypt they occur mainly in the spring, while in southern Israel and in the Mediterranean parts of northern Egypt, in winter and spring.

The interannual variations and the spatial distribution of rainfall in the Mediterranean and semi‐arid regions of Israel are analysed with respect to variations in the occurrence of the typical synoptic systems of the Eastern Mediterranean. The synoptic analysis is based on a daily, semi‐objective synoptic classification (Alpert et al., 2004a). The study covers the months November–March, in which 90% of the annual rainfall is obtained, mostly resulting from Cyprus lows. The interannual variations of the rainfall are well explained by the synoptic types, and the occurrences of Cyprus lows are highly correlated with the rainfall. It was found that the daily and seasonal rainfall are highly dependent on the depth of the cyclone. Moreover, deep lows are more effective for the mountainous regions, due both to the enhanced orographic effect and to the fact that stronger winds, associated with deep lows, are more efficient in transporting rain‐producing clouds from the Mediterranean Sea inland. The location of the cyclone determines the spatial distribution of the rain it produces over Israel. The cyclones located east of Cyprus were found productive mainly for the southern parts of the study region, while those located to the west and north of Israel were found productive for the north of the country. The high sensitivity of the rainfall to the location of the surface cyclones emphasizes the major role that lower level moisture transport plays in rain formation. Copyright © 2009 Royal Meteorological Society