The Department of Meteorology has issued an Amber advisory for rainfall exceeding 100 mm in the Western, Sabaragamuwa, North-Western and Northern provinces and the Anuradhapura district, valid until 3.30pm on 21 October.
The department said showery conditions are intensifying across the island because of a low-level atmospheric disturbance in the vicinity of Sri Lanka. Intermittent showers or thundershowers will occur at times in the affected areas, with heavy falls likely at some locations.
The department urged the public to be prepared for possible disruptions.
Separately, the National Building Research Institute (NBRI) has issued landslide warnings for parts of five districts: Badulla, Kegalle, Matale, Nuwara Eliya and Ratnapura. The warnings are in effect until 4pm on Wednesday, 21 October.
Amber-level alerts cover parts of Kegalle and Ratnapura. Yellow-level warnings apply to vulnerable areas in all five districts.
The NBRI said continued rainfall could trigger landslides, slope failures, rockfalls and ground subsidence. It asked residents to watch for warning signs, including cracks in the ground, leaning trees and muddy water emerging from the ground, and to move to safety if any of these appear. People living in landslide-prone areas should stay alert and follow instructions from the authorities, the institute said.
Background
Heavy rain is common in Sri Lanka at this time of year. October and November fall in the inter-monsoon period and the early part of the north-east monsoon season, when thunderstorms and low-pressure systems regularly bring heavy falls to the island.
The NBRI, a state research body, issues landslide early warnings using a colour-coded scale. Yellow is the lower level of the two levels in force on this occasion, and Amber is the higher. Warnings are issued for specific divisions within each district rather than for whole districts, so conditions can differ sharply between neighbouring areas.
Districts such as Badulla, Kegalle, Nuwara Eliya and Ratnapura include steep hill-country slopes and have been among those repeatedly affected by landslides during periods of prolonged rain in past years.
What it means
Residents of the named provinces and districts can expect heavy showers until at least the afternoon of 21 October, which may disrupt roads and travel and cause local flooding in low-lying areas.
People living on or below slopes in the five districts should check whether their division is covered by the NBRI warning, and should leave the area if they see the warning signs the institute has listed. Sri Lankans abroad with relatives in these areas may wish to contact them and pass on the advisory.
