Why UAE summer fog affects travel and creates hidden health and safety risks.
Dubai: Every summer, especially during the early morning hours, dense fog blankets parts of the UAE, reducing visibility on roads and affecting travel conditions.
Although fog is commonly linked to colder climates, experts say it is a regular feature of the UAE’s hottest months. The phenomenon occurs due to a combination of high humidity, desert conditions and overnight cooling that creates the right conditions for fog formation.
Fog is essentially a cloud that forms close to the ground when water vapour condenses around tiny particles such as dust and other airborne particles.
It can vary from a light mist to dense fog, significantly reducing visibility. In severe conditions, visibility can drop to less than one kilometre and, in extreme cases, to just a few metres.
Despite its desert climate, the UAE experiences conditions that are highly favourable for fog formation during summer. Moist air from the Arabian Gulf and the Arabian Sea moves inland during the evening, bringing elevated humidity levels.
After sunset, the desert surface rapidly loses heat through a process known as radiative cooling, causing the air near the ground to cool. When the air temperature falls to the point where it becomes saturated, water vapour condenses into millions of tiny droplets suspended close to the surface, creating what meteorologists refer to as radiation fog.
According to Ibrahim Al Jarwan, Chairman of the Emirates Astronomy Society and a member of the Arab Union for Astronomy and Space Sciences, this type of fog becomes more common during the latter part of summer, especially in August, when humid air masses become more frequent across the UAE. Even a small drop in overnight temperatures can trigger dense fog once the air reaches saturation.
A key factor in fog formation is the dew point — the temperature at which air becomes fully saturated with moisture. When the overnight temperature falls to the dew point, water vapour begins to condense into tiny droplets, creating fog. The smaller the gap between the air temperature and the dew point, the higher the chances of fog developing.
The UAE’s geography also contributes to the phenomenon. While the country has a desert climate, its location near the warm Arabian Gulf provides a steady source of moisture. Evening sea breezes carry humid air inland, where it interacts with dust and fine sand particles in the atmosphere. These particles act as condensation nuclei, helping water droplets form and increasing the likelihood of fog.
Due to the regular combination of these conditions, the UAE can experience around 50 fog days each year, despite being among the hottest countries in the world.
The seasonal fog phenomenon frequently affects road, air and maritime transport across the UAE, particularly between June and September, leading the National Centre of Meteorology to issue weather alerts during periods of reduced visibility.
Dense fog can form quickly in the hours before sunrise, making it harder for drivers to judge speed, distances and road conditions. The resulting drop in visibility can significantly increase the risk of traffic accidents.
Authorities advise motorists to check weather updates before travelling, reduce speed in foggy conditions, leave extra space between vehicles and use low-beam headlights. High beams are discouraged as they can reflect off fog droplets and further impair visibility. When conditions become unsafe, drivers are advised to pull over in a safe location away from traffic until visibility improves.
Fog can also have health implications, particularly for people with asthma, chronic respiratory conditions or cardiovascular issues. Extended exposure to cool, damp air may irritate airways and worsen breathing problems, while older adults and vulnerable groups may face additional strain on the heart during cool, humid mornings.
