Thiruvananthapuram: The Northeast monsoon is likely to arrive in Kerala on October 15 or 16, the India Meteorological Department (IMD) has said. Heavy rainfall accompanied by thunder and lightning is expected across the state over the coming days.

An orange alert has been issued for four districts — Pathanamthitta, Kottayam, Idukki and Ernakulam for Thursday (October 15), with very heavy rainfall likely in isolated places.

Very heavy rainfall is defined as precipitation ranging from 115.6 mm to 204.4 mm within 24 hours. Thunder and lightning are also likely.

A yellow alert has been issued for Thiruvananthapuram, Kollam, Alappuzha, Thrissur, Palakkad, Malappuram, Kozhikode and Wayanad on Thursday. The alert indicates the possibility of isolated heavy rainfall, with precipitation ranging from 64.5 mm to 115.5 mm within 24 hours. Thunder and lightning are also expected.

Rain alerts have been issued for 12 districts, with Kannur and Kasaragod being the exceptions on Thursday. The Meteorological Centre and the Kerala State Disaster Management Authority have urged the public to take necessary precautions.

Rainfall is likely to intensify in northern Kerala from Friday (October 16). The public has also been advised to strictly follow the lightning safety guidelines issued by the Disaster Management Authority.

District-wise rain alerts

Orange alert

October 15: Pathanamthitta, Kottayam, Idukki and Ernakulam.

Yellow alert

  • October 15: Thiruvananthapuram, Kollam, Alappuzha, Thrissur, Palakkad, Malappuram, Kozhikode and Wayanad.

  • October 16: Pathanamthitta, Idukki, Palakkad, Malappuram, Kozhikode, Wayanad, Kannur and Kasaragod.

  • October 17: Pathanamthitta, Kottayam, Idukki and Ernakulam.

  • October 18: Pathanamthitta, Kottayam and Idukki.