In light of an upcoming spell of monsoon rain from Friday to Sunday, the Meteorological Department has issued an urban flooding warning for Karachi, Thatta and Hyderabad.

According to a Met Department notification, a "well marked low-pressure monsoon system has formed over the northern part of Bay of Bengal".

The system is likely to enter the lower parts of Pakistan late on August 9 [Friday] and stay in the region till August 11 [Sunday].

The system will cause widespread rains and thunderstorms in Karachi, Hyderabad, Mirpurkhas and Thatta. Sporadic rains will also be witnessed in Zohb, Kalat, Naseerabad, Makran, Sukkur and Larkana division.

All relevant departments have been asked to stay on high alert during the monsoon period.

The rains will hit at a time when various clean-up drives have been started in Karachi, Hyderabad and Sukkur to make sure that the rains cause the least possible inconvenience to citizens.

The drives were taken up after the first monsoon spell showed major flaws in Sindh's garbage disposal systems.

Sewage and rain nullahs were clogged with plastic bags and other garbage, causing rain water to gather on streets and main arteries of cities, causing distress to citizens and paralysing day to day activities.