The forecast attributed the expected showers to the pre-monsoon system that has gripped the entire country and is expected to intensify over the next 36 to 48 hours.
The Meteorological department expects normal monsoon rains this year and says that at present the country is receiving pre-monsoon rains. The rainy season will start on July 1.
The pre-monsoon showers are expected to raise river flows and may inundate low-lying areas in cities like Peshawar, Rawalpindi, Gujranwala and Lahore.
River Kabul and its tributaries which are already in medium to low flood, are expected to further swell after the rain.
In its latest advisory, the department has predicted widespread thundershowers in upper parts of Khyber Pakhtunkhwa (Malakand, Hazara, Peshawar and Kohat divisions) and scattered rains in southern parts of the province (Bannu and Dera Ismail Khan divisions).
Widespread rains are likely in upper and central parts of Punjab (Rawalpindi, Sargodha, Faisalabad, Lahore, Gujranwala and Sahiwal divisions) and Islamabad while scattered showers have been forecast for southern Punjab (Multan, Dera Ghazi Khan and Bahawalpur divisions).
Heavy to very heavy thundershowers are expected at isolated places in Rawalpindi, Lahore, Gujranwala, Sargodha and Sahiwal divisions.
The possibility of flash flooding over the hills of Koh-i-Suleman range and urban flooding in the above-mentioned cities cannot be ruled out, the advisory warns.
Widespread rain is expected in Kashmir, heavy at places and moderate at others. Scattered rain is likely in Gilgit-Baltistan. READ MORE