These four districts are Ratnapura, Kalutara, Galle, and Matara.
People living in all mountainous areas, manmade cut slopes and roads within the district, especially all the landslide susceptible areas previously identified by National Building Research Organization (NBRO) should be alert in this regard, the center said.
Those living in the above vulnerable areas should be extra vigilant and should be ready to move into safe places if heavy rains continue, it further added.