Kerala's government has described the crisis -- one of the worst in decades -- as "extremely grave" and rescue operations are underway to help thousands who remain trapped by floodwaters.
"The chief minister has confirmed 164 deaths. Around 100 people died in the last 36 hours alone," an official in the Kerala government's public relations department told AFP.
Local reports indicated an even higher toll with thousands still waiting for relief and rescue across the flood-ravaged state.
Prime Minister Narendra Modi on Friday said that he had discussed the flood situation with Vijayan as more troops and rescue workers were deployed across Kerala.
"Later this evening, I will be heading to Kerala to take stock of the unfortunate situation," Modi said on Twitter.
The state, famed for its palm-lined beaches and tea plantations, is always pommelled by the annual monsoon but this year's damage has been the most severe in almost a century.
More than 150,000 people made homeless across the state have moved into some 1,300 relief camps.
Vijayan's office Friday posted a fresh warning for around 33 million residents of Kerala.
"Alert: all districts apart from Kasargod are under red alert... heavy rains may affect these 13 districts. Everyone please be cautious," his office tweeted.
Even before the latest warning, locals like Ajo Varghese have been posting desperate appeals for relief and rescue on social media.
"My family and neighbouring families are in trouble with flood in Pandanad nakkada area in Alappuzha," Varghese said in a viral Facebook post.
"No water and food. Not able to communicate from afternoon. Mobile phones are not reachable and switch off. Please help... No rescue is available," he added.
A state official told AFP that apart from the new rainfall warnings, a breakdown of the local communication system was making it difficult for them to reach local people who may be in urgent need in the worst-affected areas.
The government says 10,000 kilometres (6,000 miles) of Kerala roads have been destroyed or damaged and tens of thousands of homes partially or completely damaged.
The gates of at least 34 major dams and reservoirs across the state have been opened in the last few days as water levels reached danger levels.
North and central Kerala has been worst-hit by the floods with the international airport in main city of Kochi shut until at least August 26.
Published : August 17, 2018
By : Agence France-Presse Kochi, India