Ten people were killed and five others missing during the past 24 hours as heavy rains and strong winds lashed out across Sri Lanka, the Disaster Management Center (DMC) said.
Most of the deaths were reported from the capital Colombo as more than 150 mm of rain was experienced since the early hours of Sunday.
The Health Ministry said that it had instructed all health directors in provinces to be on alert and ready for any emergency in hospitals.
The Ministry added it had made all arrangements to airlift patients in critical condition to larger hospitals from village areas as the flood worsened.