The Pakistan Meteorological Department (PMD) on Thursday issued an alert for a tropical cyclone, predicting torrential rain and squally winds along the Sindh-Makran coast.

Late on Thursday, the Sindh education department announced that all private and government schools and colleges would remain closed on Friday.

The PMD, also known as the Met Office, in its latest update said that a depression over the northeast Arabian Sea had moved west-northwestward at a speed of 20 kilometres per hour during the last 12 hours, and now stood at a distance of about 240km east-southeast of Karachi.

"The system is likely to strengthen further into a cyclonic storm during the next 12-18 hours and move west-northwestwards," the alert said.

Under the influence of the system, widespread rain, wind thunderstorms with scattered heavy to very heavy rainfall and squally winds were likely in Karachi, Hyderabad, Thatta, Badin, Mirpurkhas, Thaparkar, Umerkot, Sanghar, Shaheed Benazirabad, Nausheroferoz, Tando Muhammad Khan, Tando Allayar, Dadu, Jamshoro, Sukkur, Larkana, Jacobabad, Shikarpur and Ghotki districts from Thursday night till Oct 2 (Saturday), it added.

Widespread rain, wind thunderstorms with scattered heavy to very heavy rainfall are also likely in Gwadar, Lasbela, Awaran, Kech, Khuzdar, Kalat and Panjgur districts of Balochistan from Thursday to Sunday, the department said.

The department predicted that sea conditions would remain rough till Sunday and advised fishermen to refrain from venturing into the water until then.

"Torrential rains may generate urban flooding in Karachi, Badin, Thatta, Hyderabad, Dadu, Mirpurkhas, Shaheed Benazirabad, Lasbela, Somiani, Ormara, Pasni, Gwadar, Turbat and Jiwani," the Met department said.

It further warned that the windstorm may also damage vulnerable structures.

It said that the PMD Tropical Cyclone Warning Centre, Karachi was closely monitoring the system and told authorities concerned to remain on high alert during this period.

Under the effect of the system, light rain accompanied by gusty winds hit parts of Karachi on Thursday evening.

Weatherman Sardar Sarfaraz told Dawn.com that the weather system's direction would be determined after it intensified into a cyclone — which is likely to happen between Friday morning and afternoon. The system was likely to move towards the Makran coast or Oman, he said.

Earlier, in a video update, Sarfaraz reiterated that the weather system was likely to cause heavy rainfall and gusty winds, and would make for treacherous conditions at sea.

He said that there was a threat of urban flooding in Karachi, Hyderabad, Thatta, Badin, Nawabshah, Dadu, Ormara, Pasni and Jiwani, adding that low-lying areas and islands could also go underwater.

He compared the oncoming cyclone to another one from 2007, calling them "similar". He said back then the low pressure system had become a cyclone after reaching the Arabian Sea, similar to what was happening now.

He said the cyclone in 2007 had hit the area between Ormara and Pasni, and caused substantial damage in various districts of Balochistan.

Electricity poles fall, schools closed in Karachi

Meanwhile, the bridge near Millennium Mall on Karachi's Rashid Minhas Road saw traffic congestion after three electricity poles fell down on the bridge.

The flow of traffic normalised after the poles were removed off the bridge, according to traffic police.

Meanwhile, Karachi Commissioner Naveed Ahmad Shaikh directed all deputy commissioners to have all "unsafe" billboards and hoardings removed from their respective districts, especially those installed on buildings and rooftops.

He also advised citizens to avoid leaving their homes unnecessarily, and especially avoid visiting beaches.

The commissioner also imposed a ban on bathing in the sea under Section 144 of the criminal procedure code in view of the Met Office's advisory. The ban will last until October 5.

Need to activate civic bodies

On Wednesday, Dr Noman Ahmed — a seasoned architect and urban planner — called for preparedness in view of urban flooding threat and inundation of coastal areas.

“There is an immediate need to activate civic bodies for rescue operations and disaster management. Once this impending situation is over, the government should put its act together to find a long-term solution to urban flooding that the city frequently faces,” he said.

According to Dr Ahmed, Karachi’s flooding is mainly connected to encroachment of its stormwater drains. “We have also seen that rainwater’s drainage has completely been ignored in development works as well as in roads’ carpeting and up-gradation that have been carried out in the city in recent years.”

On the government side, director general Syed Salman Shah of the Provincial Disaster Management Authority (PDMA) explained that vulnerable populations and areas had been identified and a plan of action was ready.

“We are constantly in contact with the Met department and will take action in view of Thursday’s situation. Each district has been provided with two additional suction pumps while big drains in the city have been cleared,” he said.