Heavy rain has lashed several parts of northern China, flooding streets and halting transport services. And here in the capital Beijing, the storm alert was raised from yellow to orange, as authorities advised against non-essential travel and warned of landslides in mountainous regions.

Photo taken by a cellphone shows vehicles stranded in water at a flooded tunnel outside the Beijing West Railway Station in Beijing, capital of China, July 20, 2016. Beijing's meteorological bureau issued an orange alert for rainstorm Wednesday noon. (Xinhua/Liu Guannan)

This is one of the key thoroughfares of southwestern Beijing. And the capital's morning rush-hour traffic just got worse.

"I thought I could drive through..obviously I was wrong..the road's too slippery."

The driver had to leave his car to go find help, but his stranded vehicle obviously wasn't enough to deter the more daring travellers.

An orange alert, the second highest of China's four-tier warning system, was issued on Wednesday as heavy rain hit Beijing, disrupting traffic and forcing flight cancellations.

Around 70 millimetres of rain fell in central and southern Beijing in just six hours.

"I'd like to advise our residents to be prepared and minimize outdoor activities. Special preparation efforts are needed for western mountainous areas of Beijing, and south-eastern regions of Beijing," Liu Hongwei, chief engineer of Beijing Flood control Office, said.

Local authorities are leaving nothing to chance. The Beijing Flood Control headquarters has initiated a level two emergency response. Back in 2012, the capital saw serious flooding, and 79 people died. This time around, they are pulling out all the stops to ensure safety.

"This is an important road and also the low point of the area. We've been making the rounds in the area every hour to make sure the water gets drained properly," Beijing Drainage Group employee said.

A landslide occurred at a section of the Great Wall in north-western Beijing. Fortunately no one was injured and emergency response staff were soon at the scene working to contain any further risks.

The heavy rain is expected to last until Wednesday night and then ease up.  Beijing issued a blue alert on Tuesday and raised it to yellow on Wednesday morning, before raising it again in the early afternoon.