Severe fog caused disruption to flights yesterday, with some frustrated passengers reporting delays of up to nine hours.
A total of 21 flights were diverted at Dubai International, with three more cancelled and other arrivals and departures held up.
At Abu Dhabi International Airport, seven flights were diverted - four to Muscat, two to Doha and one to Sharjah - several were delayed and two were cancelled.
On the roads, a number of accidents were recorded in Dubai, none fatal.
More fog was also forecast for this morning, raising fears of further travel chaos.
Among those caught up in yesterday's delays was Hayat Shammas, 37, from Jordan. Her flydubai flight from Amman to Dubai was diverted to Fujairah because of fog and grounded there for about nine hours, from 2.30am.
"At the beginning, they left us on the plane for about two and a half hours. We stayed inside the plane in Fujairah and then we spent time in the airport and then on the plane for two and a half hours before we took off," she said after landing in Dubai yesterday lunchtime.
"Our passengers' safety is of paramount importance, however, the weather conditions resulted in an unavoidable delay to this flight. We apologise for the inconvenience the adverse weather conditions caused our passengers," a flydubai spokeswoman said.
Carolina Van Soest, 19, was stuck in Doha for three hours en-route from London to Dubai, because of the fog. Her connecting plane from Doha took off three hours later than scheduled yesterday morning.
"The cabin crew said Dubai airport was closed because of the fog. There was a lot of frustration from some of the passengers. Some missed meetings and others connections," she said.
"I was very relieved to land in Dubai. I thought the UK was going to be the problem. I was worried because of the snow," said the student, who is in Dubai on holiday.
Many frustrated travellers took to Twitter to vent their frustration. "After spending the last 10 hours n #Dubai_Airport … Finally OFF to #Bahrain," and "Dubai airport mayhem right now!! Missed my connecting flight along with the rest of the airport."
An Emirates airline spokesman said the fog in Dubai had caused significant delays to some flights leaving the city yesterday but none of their flights had been cancelled.
"Flights EK846 from Doha and EK136 from Venice were diverted to Muscat due to the weather conditions," he said. "Emirates apologises for any inconvenience caused by these delays, however, the safety of our passengers and crew is of the highest priority."
An Etihad Airways spokeswoman said two flights were cancelled: "There has been some disruption to our operation, which has resulted in the cancellation of two flights to Erbil and Muscat.
"There were delays to inbound flights and two diversions, which have subsequently arrived in Abu Dhabi. All customers are advised to check in as normal."
On the roads in Dubai there were several accidents, including one in which a minibus collided with a bicycle at about 7am on Ittihad Road, leaving the cyclist with slight injuries.
Police warned drivers to be careful, adhere to speed limits and ensure their windscreen wipers and lights are in working order.
"Drivers should reduce speed during heavy fog as well as leave enough distance between vehicles, use lights and change lanes only when it's important," a Dubai Traffic Police spokesman said.
The National Centre of Meteorology & Seismology said fog and mist affected the whole country yesterday, with visibility dropping to 100 metres and less.
"There is a chance of fog tomorrow [Thursday]," a spokesman said, and it would be "almost the same".
"All the roads in the UAE will be affected by the fog, so the visibility will be reduced, so take care everybody."
There is also a chance of a foggy start tomorrow but it is not expected to be as widespread.