Thiruvananthapuram | As heavy rains lashed parts of Kerala on Thursday, the IMD issued an 'orange alert' in the three southernmost districts of the state.

The India Meteorological Department (IMD) sounded the 'orange alert' in Thiruvananthapuram, Kollam and Pathanamthitta districts of the state for three hours from 7.15 am.

It said that "thunderstorms with moderate rainfall and maximum surface wind speed, occasionally reaching 50 kmph (in gusts), were very likely to occur" in parts of these districts.

Thunderstorms, moderate rainfall and strong winds are also likely in parts of Alappuzha, Kottayam and Idukki districts of the state, it said.

An 'orange alert' denotes 'very heavy rainfall' of 11 to 20 cm.