As Karachi and other parts of Sindh and Balochistan reel from three days of torrential rains that brought life to a virtual halt in many areas, the Met Office on Friday said another monsoon spell was likely to hit the two provinces starting tomorrow.

The latest rain-bearing system is likely to enter Sindh tomorrow and will cause rains in Sindh and Balochistan from Saturday to Monday, the Pakistan Meteorological Department (PMD) said in a weather advisory.

Under the influence of the system, rain/wind thundershowers, with isolated heavy to very heavy falls, are expected in Karachi, Hyderabad, Thatta, Badin, Shaheed Benazirabad, Dadu, Tharparkar, Nagarparkar, Mirpurkhas, Islamkot, Umerkot, Sanghar, Sukkur and Larkana from Saturday evening till Monday, according to the advisory.

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Rain-thundershowers with isolated heavy falls are also likely in the Balochistan areas of Lasbela, Khuzdar, Awaran, Barkhan, Zhob, Musakhel, Loralai, Kohlu and Sibbi on Sunday and Monday.

The PMD said rain accompanied by thundershowers is also expected in parts of Punjab including Bahawalpur, Rahim Yar Khan, Khanpur, Rajanpur, Dera Ghazi Khan, Multan, Khanewal and Sahiwal during the period.

The advisory warned that heavy rainfall "may further aggravate existing urban flooding/water logging in Karachi, Hyderabad, Thatta, Mirpurkhas and Badin on Sunday and Monday".

"Heavy downpour may generate flash flooding in Sibbi, Kalat, Khuzdar, Lasbela and Dera Ghazi Khan during the period," it further said.

The PMD advised all concerned authorities to remain alert ahead of the new spell.

On Thursday, the three-day spell of record-breaking monsoon rains played havoc with Karachi’s infrastructure, flooding all key roads, submerging underpasses and streets and paralysing all segments of life. The crisis-like situation forced the Sindh government to invite the intervention of Prime Minister Imran Khan who ordered immediate rescue operations for thousands of affected people.

The rain started in the first half of the day continued for more than three hours in most parts of the city and took a brief break before it returned an hour before the sunset. The traffic system collapsed, the drainage infrastructure and power supply lines severed due to heavy rains.

At least 19 people were killed on Thursday in various rain-related incidents, including electrocution, drowning and collapse of concrete infrastructures. With these casualties, the death toll in the three-day rains rose to 30.

K-Electric was forced to suspend power to over 900 feeders, while several power installations, including substations, grid stations and power plants, were also impacted by the rising water levels.

On Friday, major thoroughfares and roads in several parts of the city remained submerged and many areas continued to face power outages.