The incidence and the intensity of the Urban Heat Island (UHI) is caused by the geography, topography, synoptic conditions, season, time of the day and the character of the built up environment (such as the size of the city, density of buildings and land use). In most cases the urban heat island is strongly evident in cities located in high latitudes, in winter, at night and during stable weather conditions. In the study of desert cities, such as Kuwait, Phoenix and Mexico City, measurements showed that a relatively weak UHI was developed compared with cities of a similar size in non-arid zones.

The city of Eilat, located in an extremely hot and dry climate, is situated on low mountain slopes and along the Red Sea shore with a complex and varied topography. Climatic measurements were taken during different seasons (February and August) using 3 mobile traverses, measuring temperature, relative humidity and air pressure. The results showed that the UHI is more pronounced in the day than the night, and in summer than in winter, when the UHI was of a value of up to 2 degrees Celsious . During the night the UHI occurred in the city centre, located on the lower mountain slopes, and shifted during the day to the Hotels' quarter along the seashore. During the summer daytime the city developed a UHI of a value of up to 3.5 dgrees Celsious, measured in the area of Hotels' quarter, while a minor UHI occurred in the city centre.

The evidence of an UHI in an arid urban environment is more pronounced than expected, especially during summer. Therefore, in the specific case of Eilat, future planning should take into account the location and layout of urban development.