Most parts of the state were enveloped with fog, crippling road and rail transport. The arrival of Prime Minister Narendra Modi, who is arriving in his parliamentary constituency Varanasi Thursday, was also delayed by over an hour due to poor visibility.
More than three dozen trains were late and the flights schedule was also hit.
The minimum temperature here was 2.5 degrees Celsius Wednesday as scores of Christians braved the inclement weather to attend midnight masses in churches across the city.
The Met Office has forecast similar weather in the coming days.
The severe cold has led to the death of 18 people since Wednesday. The deaths were reported from Jaunpur, Mirzapur, Bhadohi, Varanasi, Chandauli and Ghazipur. The toll due to cold-related deaths this week has risen to 70, officials said.
The cold wave has intensified in the eastern parts of the state. Muzaffarnagar was the coldest in the state with 2.4 degrees Celsius and state capital Lucknow was a close second with 2.5 degrees celsius.
Meerut recorded a low of 3.1 degrees Celsius, while it was 3.7 degrees Celsius in Kanpur. (IANS)