Climatology
This page presents Yemen, Rep.'s climate context for the current climatology, 1991-2020, derived from observed, historical data. Information should be used to build a strong understanding of current climate conditions in order to appreciate future climate scenarios and projected change. You can visualize data for the current climatology through spatial variation, the seasonal cycle, or as a time series. Analysis is available for both annual and seasonal data. Data presentation defaults to national-scale aggregation, however sub-national data aggregations can be accessed by clicking within a country, on a sub-national unit. Other historical climatologies can be selected from the Time Period dropdown list.
Observed, historical data is produced by the Climatic Research Unit (CRU) of University of East Anglia. Data is presented at a 0.5º x 0.5º (50km x 50km) resolution.
Yemen is a largely arid sub-tropical country where temperature depends primarily on elevation, and, in the coastal areas, is determined by distance from the sea. Mean temperatures in the highlands range from below 15°C in winter to 25°C in summer, and in the coastal lowlands from 22.5°C in winter to up to 35°C in summer.
Rainfall regimes differ in the highlands and in coastal areas, with relatively little rainfall received in the center of the country. The annual frequency of rain days increases with elevation, with the mean number of wet days showing a strong decline from west to east. Coastal areas receive 80% of the annual rainfall during the winter months, while rainfall in the highlands follows two distinct rainy seasons: the saif (April-May) and the kharif (July-September). The saif rains are governed by the north-west trade winds (entering the Red Sea Convergence Zone), while kharif rainfall is governed by mechanisms of the Inter-Tropical Convergence Zone. Kharif rains typically fall in short events.