Why homes in the UAE and GCC are so humid: the climate, the Gulf and your AC
The short answer
The Arabian Gulf is shallow and very warm, so it puts a lot of moisture into the air along the coast. In Dubai the average dew point reaches about 27 °C in August. Any surface in your home that the AC has cooled below that point, such as glass, ducts, walls or wardrobes against them, can collect moisture. Humid air also leaks in through doors and balconies and builds up when the AC cycles off. That is why coastal GCC homes need active humidity control, not just cooling.
Relative humidity hides the real story
Dubai's average relative humidity looks moderate on paper: about 50 to 55% in the summer months. The number that matters indoors is the dew point, the temperature at which air becomes saturated and water starts to condense. In July and August, Dubai's average dew point is around 26 to 27 °C. An air-conditioned room at 23 °C is several degrees colder than that.
In practice this means that outdoor air coming into a cooled home carries more water than the cool indoor air can hold. That moisture ends up on the coldest surfaces first, or has to be removed by the AC or a dehumidifier.
Dubai's dew point, month by month
| Month | Average relative humidity | Average dew point |
|---|---|---|
| Jan | 65% | 9.8 °C |
| Feb | 64% | 11.2 °C |
| Mar | 61% | 13.5 °C |
| Apr | 54% | 17.1 °C |
| May | 50% | 20.9 °C |
| Jun | 55% | 23.8 °C |
| Jul | 55% | 26.5 °C |
| Aug | 53% | 27.2 °C |
| Sep | 59% | 24.9 °C |
| Oct | 60% | 21.1 °C |
| Nov | 61% | 15.7 °C |
| Dec | 65% | 11.3 °C |
Dubai Meteorological Office averages. Dew points above about 24 °C, from June to September, are when indoor moisture problems peak in AC-cooled homes.
Why the Gulf makes coastal air so humid
The Arabian Gulf has the highest average summer sea surface temperatures in the global ocean, according to a 2025 study in Ocean Science. Mean summer temperatures range from below 28 °C to above 35 °C across the Gulf, and they have risen by about 0.31 °C per decade since 1980.
Because the Gulf is shallow, its water warms quickly and evaporates strongly, which drives very high humidity along the coast. Researchers at MIT and Loyola Marymount have highlighted Gulf cities including Dubai, Abu Dhabi and Doha as a hotspot where heat and humidity combine.
The same pattern affects coastal cities across the GCC: Sharjah, Ajman and Ras Al Khaimah in the UAE, Doha, Manama, Kuwait City, Dammam and Al Khobar on the Gulf, Muscat on the Gulf of Oman, and Jeddah on the Red Sea.
How humidity gets inside a sealed, air-conditioned home
- Every door and balcony opening lets humid outdoor air in.
- Gaps around windows, ducts and service openings leak air continuously.
- AC cycling: when the compressor stops, it stops removing moisture, while the fan may keep moving humid air.
- Empty homes in summer: AC set high or switched off while the family travels lets humidity climb for weeks.
- Daily life: showers, cooking, laundry and people add moisture inside.
What to do in a UAE or GCC home
- Measure room by room for a week, including when the AC is off.
- Keep humidity below 60%. Dubai Municipality guidance recommends below 60%, and below 50% where feasible.
- Maintain the AC: clean filters and check that condensate drains flow freely.
- Seal the obvious leaks: balcony door seals, window gaps and duct openings.
- Dehumidify the rooms that stay humid, especially closed bedrooms, wardrobes, storage and laundry rooms, and homes left empty in summer.
Frequently asked questions
Why is Dubai so humid in summer?
The Arabian Gulf is shallow and very warm, so it evaporates strongly and loads coastal air with moisture. Dubai's average dew point reaches about 27 °C in August.
What is a dew point and why does it matter indoors?
It is the temperature at which air becomes saturated and water condenses. When the outdoor dew point is higher than the temperature of surfaces in your AC-cooled home, moisture condenses on them, which leads to damp and mold.
Is humidity a problem in Abu Dhabi, Doha and other GCC cities too?
Yes. Coastal cities around the Gulf, the Gulf of Oman and the Red Sea share the same pattern of hot, humid summers. Homes near the water are the most exposed.
Does air conditioning remove humidity?
Partly, while the compressor runs. It does not control humidity directly, and moisture builds up when the AC cycles off, in closed rooms and in empty homes.
Sources
- Dubai Meteorological Office climate averages for Dubai, as tabulated in Climate of Dubai (Wikipedia). Accessed 20 October 2026.
- Lachkar, Z., Pauluis, O., Paparella, F., Khan, B. and Burt, J. A. (2025). Local and remote climatic drivers of extreme summer sea surface temperatures in the Arabian Gulf. Ocean Science, 21, 3241–3263.
- Pal, J. S. and Eltahir, E. A. B. (2015). Future temperature in southwest Asia projected to exceed a threshold for human adaptability. Nature Climate Change. Summary: MIT Eltahir group.
- HawaQ, Ideal indoor humidity in UAE homes, summarising Dubai Municipality's Technical Guidelines for Indoor Air Quality (DM-HSD-GU119-IAQ, v4, Dec 2024) and the US EPA's A Brief Guide to Mold, Moisture and Your Home. Accessed 20 October 2026.