IMD Chennai has placed seven districts on red alert as Vellore, Karur and Salem crossed 43 °C for five consecutive days between 11–15 May. Eastern districts are seeing high humidity rather than peak temperature; western districts are dry-hot.

The State Disaster Management Authority opened 412 cooling shelters in collaboration with municipal corporations. The Labour Department has issued an outdoor-work advisory covering construction, road work, and agricultural operations between 12:00–16:00 IST until 22 May, with mandatory rest breaks and ORS access.