Police reduced speed limits in Abu Dhabi as thick fog descended over the emirate early on Thursday.
The bad weather affected an area near Al Ruwais in the west all the way to the capital.
Drivers were told not to exceed 80kph on several roads as visibility dropped below 1 kilometre.
The fog is expected to burn off by about 8am, leaving a hazy and partly cloudy day, which will be warm during the day.
Temperatures will reach 37°C inland and 35°C on the coast.
Winds will be light to moderate.
The sea will be slight to moderate in the Arabian Gulf and slight in Oman Sea.
Friday will be another hot and hazy day, with temperatures of up to 37°C in Abu Dhabi and Dubai.
But the mercury will plunge overnight to reach a maximum of 27°C on Saturday, which could start with mist and fog. Moderate winds, which will be gusty at times, will kick up dust and sand.
Temperatures will remain cooler on Sunday before climbing again.
Last month, the UAE had about 12 days of fog but it was a drier than average month with less rainfall than in years gone by.
In December, President Sheikh Khalifa called for prayers for more.
Results
2pm: Serve U – Maiden (TB) Dh60,000 (Dirt) 1,400m; Winner: Violent Justice, Pat Dobbs (jockey), Doug Watson (trainer)
2.30pm: Al Shafar Investment – Conditions (TB) Dh100,000 (D) 1,400m; Winner: Desert Wisdom, Bernardo Pinheiro, Ahmed Al Shemaili
3pm: Commercial Bank of Dubai – Handicap (TB) Dh68,000 (D) 1,200m; Winner: Fawaareq, Sam Hitchcott, Doug Watson
3.30pm: Shadwell – Rated Conditions (TB) Dh100,000 (D) 1,600m; Winner: Down On Da Bayou, Xavier Ziani, Salem bin Ghadayer
4pm: Dubai Real Estate Centre – Maiden (TB) Dh60,000 (D) 1,600m; Winner: Rakeez, Patrick Cosgrave, Bhupat Seemar
4.30pm: Al Redha Insurance Brokers – Handicap (TB) Dh78,000 (D) 1,800m; Winner: Capla Crusader, Bernardo Pinheiro, Rashed Bouresly
How green is the expo nursery?
Some 400,000 shrubs and 13,000 trees in the on-site nursery
An additional 450,000 shrubs and 4,000 trees to be delivered in the months leading up to the expo
Ghaf, date palm, acacia arabica, acacia tortilis, vitex or sage, techoma and the salvadora are just some heat tolerant native plants in the nursery
Approximately 340 species of shrubs and trees selected for diverse landscape
The nursery team works exclusively with organic fertilisers and pesticides
All shrubs and trees supplied by Dubai Municipality
Most sourced from farms, nurseries across the country
Plants and trees are re-potted when they arrive at nursery to give them room to grow
Some mature trees are in open areas or planted within the expo site
Green waste is recycled as compost
Treated sewage effluent supplied by Dubai Municipality is used to meet the majority of the nursery’s irrigation needs
Construction workforce peaked at 40,000 workers
About 65,000 people have signed up to volunteer
Main themes of expo is ‘Connecting Minds, Creating the Future’ and three subthemes of opportunity, mobility and sustainability.
Expo 2020 Dubai to open in October 2020 and run for six months
Essentials
The flights
Emirates flies direct from Dubai to Seattle from Dh6,755 return in economy and Dh24,775 in business class.
The cruise
UnCruise Adventures offers a variety of small-ship cruises in Alaska and around the world. A 14-day Alaska’s Inside Passage and San Juans Cruise from Seattle to Juneau or reverse costs from $4,695 (Dh17,246), including accommodation, food and most activities. Trips in 2019 start in April and run until September.