A bus gingerly makes its way through the heavily flooded center of Wuhan, capital of Hubei province on Thursday after torrential rain struck the city, crippling transportation. [Photo/CFP]

More than 100 millimeters of rain fell on Wuhan on Thursday, reaching an intensity of 66 mm per hour at times.

The capital of Hubei province was inundated with torrential rain with water accumulating rapidly in many downtown areas.

Authorities warned people to avoid unnecessary trips and as of 3:30 pm 71 flights had been delayed and 13 canceled due to the conditions. More than 10 flights were diverted to neighboring cities.

Many internet users posted photos of knee deep floodwater and vehicles which were nearly under water in some severely affected areas.

An internet user described the situation as the buses looking like ships as they were submerged in the rainwater.

Shanghai, Nanjing and Wuhan are three of more than 100 cities across China to be disrupted by urban flooding annually, according to the State Flood Control and Drought Relief Headquarters.

In 2012 urban flooding affected 184 cities, while in 2013 the number was 234 and last year it was 125.

Urban flood drainage is one of many concerns for city planners.

Read more about urban flood drainage check:

'Sponge City' program set to soak up urban floodwater