BBC correspondent in Hyderabad
Dehydration has been a severe problem for many state districts
Authorities in the southern Indian state of Andhra Pradesh have said that the death toll in a 17-day heat wave has now risen to 637.
The weather office has warned similar conditions will continue for another 48 hours in the state.
On Friday, the state's relief commissioner, DC Roshaiah, said 81 more deaths had been reported from around state in the previous 24 hours.
The highest number of deaths - 119 - have been reported in Nalgonda, followed by 103 in East Godavari and 98 in Prakasham district.
Dry hot winds have sent temperatures to above 47C in many places.
Mr Roshaiah said the state government had asked the administrations in all districts to set up drinking water booths.
He also instructed them to make Oral Rehydration Solution available in all affected villages to prevent dehydration.
Last year a heat wave killed more than 1,000 people in the state as temperatures reached 50C.
Earlier this week, Mr Roshaiah said the government was doing all it could to educate people on how to avoid sunstroke.
Last week the provincial government announced payments of 10,000 rupees ($214) for the families of each victim.