Kochi airport has suspended all operations till Saturday, 2pm.
The decision to suspend operations was taken after shutters of the Idamalayar and Cheruthoni dams, part of Idukki reservoir, were opened last evening to release excess water.
The airport is located near the Periyar river bank.
The airport had earlier announced it would shut down till 2pm today.
"Operations suspended to/from Cochin International Airport till 1400 hrs...due to flood level in and around Airport," the airport's official handlehad said on Twitter.
The Met department meanwhile has issued a red alert, saying heavy to very rainfall is expected till tomorrow in Wayanad, Kozhikode, Kannur, Kasargode, Malappuram, Palakkad, Idukki and Ernakulam districts.
Kerala has been hit by torrential rains in recent days. The rains, flooded rivers, and landslides have so far claimed 40 lives.
(With inputs from PTI)