The capital city of northeast China's Heilongjiang Province was hit by the biggest snowstorm of the year on Tuesday, with roads and air traffic disrupted and schools closed.

An overnight snowstorm hits Heilongjiang.[Heilongjiang Daily]

Meteorological authorities in Harbin issued the first snowstorm red alert of this year early Tuesday morning, saying the snow will continue with precipitation of 15 millimeters over six hours.

Yuan Meiying, chief weather forecaster with the provincial meteorological station, said the snowstorm starting Monday had hit 17 counties and cities in the province.

Harbin was among the worst hit, with 28 millimeters of precipitation falling from 8:00 a.m. Monday to 8:00 a.m Tuesday.

"The snow on the ground is above my ankles. It is difficult to walk downtown," said a Harbin resident surnamed Liu.

The municipal education bureau issued an urgent notice on Tuesday morning ordering the closure of primary and middle schools for Wednesday. However, many schools in Harbin had already closed voluntarily Tuesday morning.

"So far, only schools in Harbin were closed. The provincial education bureau has allowed storm-hit cities like Jiamusi, Suihua, Hegang and Yichun to make an independent decision about canceling classes if necessary," said Han Yanping, an official with the provincial education bureau.

The Taiping International Airport in Harbin has been closed since 5:30 Monday, stranding over 1,500 passengers, according to Li Feng, spokesman with the airport command and rescue center.

He said 23 flights have been canceled and another 53 delayed by Tuesday noon.

"The continuing snowfall accompanied with a strong gale made it difficult for the snow clearance. The runways are still icy and the visibility is low. It is still unknown when the airport can be reopened," he said.

Besides the air traffic, five train trips from Harbin Railway Station were canceled and 39 others were delayed by Tuesday noon.

"The railway station mobilized an all-out effort to clear snow from Monday night and reinforced security," said Li Xiaodong, deputy director of the station.

According to the China Central Meteorological Station, the snow also hit northern provinces and regions like Jilin and Liaoning provinces and Inner Mongolia Autonomous Region.