Thiruvananthapuram: The India Meteorological Department has sounded a red alert in Idukki, Pathanamthitta and Kottayam districts Kerala, as the southwest monsoon set to intensify in the southern state over the next few days.

According to PTI, the alarm has been sounded for Idukki district from July 18 to 20, Pathanamthitta and Kottayam districts for July 19. The red alert has been given from July 19 as heavy to very heavy rainfall would occur in Ernakulam district.

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

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

The officials said, Alappuzha district received heavy rainfall on July 17 with 6 cm 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 northwesterly 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 per cent rainfall deficit till July 15, official sources said.