For a huge downpour in such a short time would be of more concern to the people than the shift in the monsoon pattern caused by global warming.

“Rainfall in the twin cities, and all parts of the country, has been unusually heavy and causing flash floods,” the expert told Dawn.

“If nature maintains this pattern, southern Punjab, adjoining Khyber Pakhtunkhwa and southern Pakistan would be twice as vulnerable to serious flooding in the next 30 to 35 years.”

Dr Azmat pinpointed Charsadda, Nowshera, Attock, and Swat as the new vulnerable areas, among others in the western and southern Pakistan.

“These locations require more attention for water management and flood control authorities,” he said, stressing that instead of Kashmir and northern areas, semi-arid regions of Punjab and Khyber Pakhtunkwa and Punjab were receiving more rainfall.

Catchment areas of the existing Mangla dam, and those planned for the immediate future, had been receiving less rains for the last few years, he reminded.

“This means that we need to plan new dams farther down south. We might need a fully-fledged dam at the Jinnah Barrage. There is a definite possibility that Mangla dam becomes obsolete and we might not need the Kalabagh dam if the monsoon pattern keeps shifting farther west,” said the expert.

Dr Azmat explained that the climatic shift posed a serious threat to the agriculture, livelihood, and economies of the semi-arid regions. He cited the poor cotton production of the regions over the last three years as an example.

“We had poor cotton in 2010 because of unusual rains in southern Punjab, areas that receive few rains favourable for cotton production. We are predicting similar unusual rainfalls in 2013 again in the months of August and September when the cotton is likely ready for picking,” he said.

According to the Met Department, of the 100 potentially heavy downpours in the future, top six were likely to occur in western Punjab and the adjoining Khyber Pakhtunkhwa province.

Department experts say the monsoon pattern has altered to such an extent that all four rainfall events – the easterly and westerly currents colliding over the northern areas; the high pressure build over Tibet; depression in the Bay of Bengal and the less frequent westerly currents over Bombay – have deflected into Pakistan.

And all were likely to cause heavy downpours in a short time over western Punjab, adjoining KP and causing floods in Sindh, and even parts of Balochistan.

Dr Ghulam Rasul, Chief Meteorologist at the Pakistan Meteorological Department, also stresses the need for new dams to control and manage the future floods, and indeed use the water for agriculture and energy needs of the country.

“There is no doubt we will see more of such cloudbursts – or even worse – as the one Saidpur village of Islamabad experienced last month, when 130mm rain fell on it in less than one hour. Unless we have new dams down south, nature will wreak havoc,” he warned.

Pervaiz Amir, a senior economist and former member of the Prime Minister’s Task Force on Climate Change, endorsed most of the observations of the meteorologists.

“Extreme events, which the country experienced over longer intervals in the past, are now happening at shorter intervals of two to three years,” he said. “The 2013 rains are likely to wreak the same kind of havoc as in 2010.”

He advised farmers to adjust their crop calendar, sowing cotton two months earlier so that the crop is picked before the monsoon hits. Rice growers, on the other hand, should go for delayed planting.

“There is need to introduce new varieties of wheat, rice and sugarcane which mature faster, survive heavy, unexpected rains and prolonged drought – conditions that have already arrived and are likely to continue for the next 30 to 35 years,” said the economist.