A woman (R) wets her burqa to cool her father's head outside the Jinnah Postgraduate Medical Centre (JPMC) in Karachi, Pakistan, June 24, 2015 (Photo: Reuters)
A deadly heatwave that has killed nearly 700 people in southern Pakistan showed signs of easing on Wednesday, bringing some respite to the sweltering city of Karachi.
Temperatures in the city, which is Pakistan's largest and has seen the majority of the deaths, were forecast to peak at 38 degrees Celsius (100 Fahrenheit), down from the 40-plus highs of recent days.
Winds have shifted to the southwest, blowing cooler air into the port city from the Arabian Sea, and the Pakistani Met Office has predicted rain, which would bring lower temperatures.
The government has demanded urgent action to deal with the crisis, and the administration in Sindh province declared Wednesday a public holiday to encourage people to stay indoors out of the sun.
Some residents on Tuesday took to hosing each other down with water to avoid collapsing from heat stroke.
A state of emergency is in force in hospitals which are struggling to cope with the 3,000 people affected by heatstroke and dehydration.
The change in weather will come as welcome relief for the economic hub, where maximum temperatures have hovered around 44-45 degrees C since Saturday.
The National Disaster Management Authority has been setting up dedicated heatstroke treatment centres to try to cope with the volume of patients.
Blasting summer heat is not unusual in Pakistan, and some parts of the country regularly experience higher temperatures than those seen in Karachi this week, without serious loss of life.
But this year's heatwave has coincided with the start of the Islamic fasting month of Ramadan, during which millions of devout Pakistanis abstain from food and drink from sunrise to sunset.
The majority of the deaths in Karachi have been among the poor and manual labourers who work outdoors, prompting clerics to urge those at risk of heatstroke not to fast.
The situation has not been helped by power cuts -- a regular feature of life in Pakistan -- which have stopped fans and air conditioners from working.
Electricity shortages have crippled the water supply system in Karachi, hampering the pumping of millions of gallons of water to consumers, the state-run water utility said.