In the plains of Sindh and Punjab the mercury could rise to 48 to 50 degree Celsius on Wednesday and Thursday, the met department said in its forecast.
The met department had earlier advised people to observe caution during the scorching weather spell, which coincidentally comes with the fasting month of Ramazan.
The weather department has also forecast rainfall with dust and thunderstorms at some places in Hazara, Rawalpindi, Gujranwala divisions and Kashmir region.
The central and southern plains of the country including Sahiwal, D.G. Khan, Multan, Bahawalpur, D.I.Khan, Bannu, Sukkur, Larkana, Shaheed Benazir Abad, Hyderabad, Sibi and Naseerabad divisions will likely to affect most in the hot weather.
Hot and humid weather is expected at Rawalpindi, Gujranwala, Lahore, Faisalabad, Sargodha, Kohat and Peshawar divisions, weather forecast said.
The maximum temperature in Pakistan yesterday recorded at Sibi (52 Celsius), Jacobabad (51 Celsius), Dadu, Bahawalnagar, Rahim Yar Khan, Mohenjo Daro, Larkana (49 Celsius), Rohri, Bhakkar, Sukkur and Shaheed Benazir Abad (48 Celsius).
The weather department on Monday, predicted a hot and humid weather for Karachi in the first four days of Ramazan but denied possibility of heatwave during the holy month.
“The weather would continue to remain hot over the next few days, as is usual in the month of June, but the weather is likely to improve in the coming week,” a met department official said.
At least 1,500 people died of heat strokes and dehydration over a period of four days, in Karachi during Ramazan last year. The heatwave prevailed in the city for a week, starting from June 22.