Thiruvananthapuram | The India Meteorological Department (IMD) on Tuesday issued an orange alert in Palakkad district of Kerala for the second consecutive day due to the possibility of a heatwave there till May 2.

The IMD also issued a yellow alert in Alappuzha, Thrissur and Kozhikode districts due to the possibility of heatwaves there as well during the same period.

The meteorological department uses four colour codes - green (no action needed), yellow (watch and stay updated), orange (be prepared) and red (take action)- for weather warning.

Maximum temperatures are very likely to be around 41 degrees Celsius in Palakkad district, around 40 degrees Celsius in Thrissur district, around 39 degrees Celsius in Kollam and Kozhikode districts and around 38 degrees Celsius in Alappuzha, Kottayam, Pathanamthitta and Kannur districts between today and May 4, it said.

In the remaining districts of Thiruvananthapuram, Ernakulam, Kasaragod and Malappuram districts the maximum temperatures are likely to be 37 degrees Celsius till May 4, the IMD said.

Hot and humid conditions are likely in these districts, except in hilly areas, till May 4, it added.

The state government has already ordered closure of educational institutions in Palakkad and advised the public to exercise caution during hot days.

It had also said that the rescheduled working hours of labourers during the day have been extended till May 15 in the wake of a steady increase in temperature and due to the possible threat of a heatwave.

Authorities also advised the public to take umbrellas while going out and drink a lot of water to prevent dehydration.

Among many directives, they also urged people to avoid going out during the day as much as possible and postpone all public events to the evening.

Two persons -- a man in his 50s and an elderly woman -- had succumbed to sunstroke in Kerala on Sunday.