Thiruvananthapuram: The Indian Meteorological Department (IMD) has issued a ‘red alert’ in three districts of Kerala. The three districts are Idukki, Pathanamthitta and Kottayam.

The red alert has been issued for Idukki district from July 18 to 20, Pathanamthitta and Kottayam districts for July 19.

The red alert is a call to take immediate preventive steps, evacuate people from vulnerable areas to shelter camps and provide others with emergency kits.

The districts are likely to receive extreme heavy rainfall upwards of 20cm, an IMD official told PTI.

The officials said, Alappuzha district received heavy rainfall on July 17 with 6cm of rain.

Other districts are predicted to get isolated heavy to very heavy rainfall on these days, though a red alert has not been issued for them.

Fishermen living on the coast of Kerala and Lakshadweep area have been cautioned not to venture out to sea due to strong winds from the north-westerly direction reaching speeds of 40-50 kmph.

The southwest monsoon had set in on June 8, a week late, marking the official commencement of the four-month rainfall season.

There has been 46% rainfall deficit till July 15, official sources said.