More than 223,000 people have been affected by the adverse weather.
The bodies of 13 dead from the landslide in Aranayake have so far been recovered.
In Wattala, two boys aged 16 and nine years drowned in a pool of water.
Rescue missions
The Army has deployed 300 soldiers and sniffer dogs as 43 teams to assist in the rescue and relief provision efforts.
They have so far taken nearly 700 people to safety, said military spokesman Brig. Jayanath Jayaweera.
Twenty eight Navy teams have rescued 968 people, said Navy spokesman Capt. Akram Alavi.
The Air Force too, has deployed its helicopters for rescue missions, said AF spokesman Wing Commander Chandima Alwis.
The AF has observed 75 people trapped near a landslide site in Aranayake and informed the Army to send rescue teams there.