Heavy snowfalls have forced airports and schools in Tehran to close, while hundreds of cars have been blocked on highways out of the Iranian capital for hours.
Tehran's Imam Khomeini International and Mehrabad airports were shut due to poor visibility "until further notice," state television said on January 28.
Schools closed in several parts of the country, including the capital, and hundreds of Red Crescent teams were mobilized to bring help to stranded drivers.
Mohammad Ali Abtahi, who served as vice president to ex-President Mohammad Khatami, posted a message on social media showing his car stuck on the highway to Qom, around 150 kilometers south of Tehran.
"It's been nine hours that we are stuck out here with hundreds of other cars," he wrote.
The official IRNA news agency quoted a Red Crescent spokesman as saying that 6,600 people had been put up in emergency accommodation.
Meanwhile, the Iranian armed forces' chief of staff, General Mohammad Hossein Baqeri, said they stood ready to provide any help needed to reopen the roads.
In Tehran, power outages were reported in several neighborhoods.
Local media said that a number of electricity cables and cars were damaged when trees collapsed under the weight of the snow.
In order to prevent further accidents, Mayor Mohammad Ali Najafi took to Twitter to call on citizens to help municipal workers shake the snow from trees.
State-run Press TV said a rail service between Tehran and the northeastern city of Mashhad was also suspended.
Many western and northern provinces were affected by the snowfall that began earlier this week and peaked in the night of January 27.
Some mountainous areas received as much 1.3 meters of snow, according to IRNA.
Iran's state gas company said it was expecting a surge in demand as temperatures were set to fall to minus 20 degrees Celsius in some northern regions.
With reporting by AP and AFP