By the afternoon, most of the Mumbai's roads were waterlogged.

Highlights A red alert has been sounded by the weather office for Mumbai

Overnight rain caused water-logging in several parts of the city

Heavy rain triggered traffic disruptions and train delays

Mumbai turned into an extension of the sea on Wednesday as unprecedented rains deluged the country's financial capital, delaying flights, jamming traffic, flooding homes and having rescue teams out on the roads since morning.

In several places, the local trains grinded to a halt, and long distance trains were cancelled. In the evening office hours, the waterlogging pushed people to look for the nearest shelter, abandoning thoughts of reaching home. The met office declared a red alert for the next 24 hours, indicating that the situation might worsen. Schools and junior colleges in Mumbai, Thane and Kokan will remain shut on Thursday as a precautionary measure.

In a tweet, Yuva Sena chief Aaditya Thackeray said the city has witnessed the "heaviest rainfall so far, with the total rainfall mark exceeding the whole of September in just about 30 hours".

The Mithi River is close to the danger mark. Thus @mybmc has kept @ndrf and all concerned departments in loop for any emergency. You could help too by avoiding venturing out unless really needed, especially close to the sea. (2/n) #MumbaiRainsLive — Aaditya Thackeray (@AUThackeray) September 4, 2019

The rain had started overnight, causing water-logging in several parts of Mumbai and pushing rescue teams to areas around Mithi River, which has crossed the danger mark. Those residing around the Mithi River have been evacuated to a temporary shelter, the city's civic body said. Rescue teams are deployed in the area to help the locals. In parts of the city, people were seen moving in waist-deep water.

By the afternoon, most of the city's roads were waterlogged and local train services were stopped to nearby areas including Thane and Goregaon, leaving the passengers stranded. The east-west connector Santacruz Chembur link road was shut and Tata Power authorities said they might switch off sub-stations in view of safety concerns.

The Santa Cruz observatory said extremely heavy rainfall of 206.6 mm recorded over six hours till 2.30 pm.

Of the 150 weather stations in the Mumbai Metropolitan Region (MMR), around 100 recorded over 200 mm rainfall in the last 24 hours, the India Meteorological Department said.

The city, home to country's financial markets, has received above average rainfall in September, according to KS Hosalikar, Deputy Director General of Meteorology, IMD, Mumbai.

In a series of posts, the city's civic body advised locals to avoid "venturing near the sea" and "stay indoors in safe premises till the water in low-lying areas recedes".

In a tweet, Western Railways said: "In view of cancellation of trains due to heavy water logging on tracks at Nallasopara - Virar, Refund Counters have been opened at all reservation offices."

At the Chhatrapati Shivaji International Airport, no major air traffic disruptions were reported; however, flights were delayed. "Operations are so far normal with minor delays of 10-15 minutes," an airport official said this morning.