The mercury touched 52 degrees Celsius in south-west parts of the country as the hot spell entered its fourth day, setting a 78-year record in the city of Lahore in the central Punjab province.
Around 50 people died on Sunday in the province, where the temperature hovered around 49 degrees and prolonged power cuts added to the misery, The Nation reported on Monday.
The Sunday deaths brought the weekend death roll to around 110.
Hundreds of people have been hospitalized with sunstroke, newspapers reported, while meteorologists predicted the heat wave would last at least three more days.
Thousands of people from the plains of Punjab headed towards the northern mountain regions to find relief, many of them to Murree, a hill station and traditional summer resort located 2,300 metres above sea level.
A similar heat wave killed more than 80 in Pakistan last year.