Temperatures in Dubai and Abu Dhabi will reach the high 30s on Wednesday, while the UAE's highest temperatures will reach into the low 40s.
In Abu Dhabi and Dubai, the forecast is for a 39°C maximum.
Along the coast and islands the maximum is likely to be 37°C with 85 per cent humidity, and the mountains are expected to hit 32°C with 70 per cent humidity.
The interior is expected to reach 41°C with up to 65 per cent humidity.
The National Centre of Meteorology said Wednesday would be fair in general to partly cloudy and hazy.
There will be light to moderate winds, freshening at times, and conditions at sea will be slight in the Arabian Gulf and in the Gulf of Oman.