Rainfall is likely to strengthen over Kerala in the week ahead under the influence of a north-south trough and a cyclonic circulation that persists over south-central Bay of Bengal, the India Meteorological Department (IMD) indicated on Saturday.
Several districts have been put on yellow and orange alerts for isolated heavy to very heavy rainfall from Sunday to Wednesday, as per a weather update.
The north-south trough runs from north interior Karnataka to the Comorin area across southern Karnataka and Tamil Nadu at lower tropospheric levels. It is likely to persist till Sunday. A cyclonic circulation lies over south-central Bay of Bengal above mean sea level. It was likely to move westward towards the peninsular coast of India over next five days, the IMD said.
Alappuzha, Kottayam, Idukki, Ernakulam, Thrissur, Palakkad and Malappuram are on yellow alert for isolated heavy rainfall (6.4 cm to 11.5 cm in 24 hours) on Sunday.
On Monday, Kottayam and Idukki are on orange alert for isolated heavy to very heavy rainfall (11.5 to 20.4 cm in 24 hours), and all districts except Wayanad are on yellow alert.
Thrissur and the southern districts are on orange alert and northern districts, on yellow alert, on Tuesday. Thiruvananthapuram, Kannur and Kasaragod are on yellow alert and all other districts on orange alert, on Wednesday.
Kerala has recorded 26% deficient southwest monsoon rainfall so far from June 1 to July 30.