The India Meteorological Department has issued a yellow alert for several districts in Kerala as twin troughs continue to influence weather across the state. Heavy rainfall accompanied by thunderstorms and strong winds reaching 40 to 50 km/h is expected in isolated places today and tomorrow.

For today, May 20, the yellow alert is in effect for Alappuzha, Ernakulam, Thrissur, and Malappuram districts. Tomorrow, the warning extends to Thiruvananthapuram, Kollam, Pathanamthitta, Alappuzha, Kottayam, Idukki, and Ernakulam districts.

Heavy rainfall is defined as precipitation between 64.5 mm and 115.5 mm in a 24-hour period. One trough extends from eastern Uttar Pradesh through central Maharashtra, Marathwada, and Karnataka to Lakshadweep. Another trough runs from the southeast Arabian Sea near southern Lakshadweep through Kerala, southern Karnataka, and Rayalaseema up to a cyclonic circulation over coastal Andhra Pradesh.

The southwest monsoon is expected to arrive in Kerala around May 26, with a possible variation of four days. The current rainfall is a result of these weather systems interacting.

The rain comes as a relief from the intense heat, with several areas already experiencing heavy downpours. In Thiruvananthapuram district, very heavy rain has been reported since afternoon. Residents are advised to remain cautious and follow official warnings.