“Overall, a tendency for normal to above normal precipitation is likely over the country during September,” the office said in monthly outlook posted at its website on Thursday.

Northeastern Punjab province and the southern Sindh are expected to receive above normal rainfall, it said, adding that isolated heavy downpours can trigger flash flooding.

The military said on Thursday it had evacuated some 50,000 people, including 1,000 by air, since rescue efforts began.

We lost our house to the rain and floods, we’re going to Karachi to our relatives. No one has come to help us
Allah Bakash

The United Nations has appealed for $160 million to help with what it has called an “unprecedented climate catastrophe”. Britain on Thursday pledged $17 million in aid.

“We’re on a high alert as water arriving downstream from northern flooding is expected to enter the province over the next few days,” Sindh provincial government spokesman Murtaza Wahab told Reuters.

Wahab said a flow of some 600,000 cubic feet (17,000 cubic metres) per second was expected to swell the Indus, testing its flood defences.

Pakistan received nearly 190 per cent more rain than its 30-year average in the quarter from June to August, totalling 390.7mm (15.38 inches).

Sindh, with a population of 50 million, has been hardest hit, getting 466 per cent more rain than the 30-year average.

Pakistan received nearly 190 per cent more rain than its 30-year average in the quarter from June to August, totalling 390.7mm. Sindh, with a population of 50 million, has been hardest hit, getting 466 per cent more rain than the 30-year average

Some parts of the province look like an inland sea with only occasional patches of trees or raised roads breaking the surface of murky flood waters.

‘No Help’

Hundreds of families have taken refuge on roads, the only dry land in sight for many. Villagers rushed to meet a Reuters news team passing along one road near the town of Dadu on Thursday, begging for food or other help.

Many are headed for urban centres, like the port city of Karachi, which has for now escaped the flooding.

“We lost our house to the rain and floods, we’re going to Karachi to our relatives. No one has come to help us,” said Allah Bakash, 50, leaving with his family and belongings loaded on a truck.

The floods have swept away homes, businesses, infrastructure and roads. Standing and stored crops have been destroyed and some 2 million acres (810,000 hectares) of farm land inundated.

The government says 33 million people, or 15 per cent of the 220 million population, have been affected.

The National Disaster Management Authority said some 480,030 people have been displaced and are being looked after in camps but even those not forced from their homes face peril.

“ More than 3 million children are in need of humanitarian assistance and at increased risk of waterborne diseases, drowning and malnutrition due to the most severe flooding in Pakistan’s recent history,” the U.N. children’s agency warned.

The World Health Organisation said that more than 6.4 million people were in dire need of humanitarian aid.

Aid has started to arrive on planes loaded with food, tents and medicines, mostly from China, Turkey and United Arab Emirates.

Aid agencies have asked the government to allow food imports from neighbouring India, across a largely closed border that has for decades been a front line of confrontation between the nuclear-armed rivals.

The government has not indicated it is willing to open the border to Indian food imports.

The UK’s foreign minister Liz Truss said on Thursday the country had made a £15 million ($17.4 million) donation that would be used to provide water, sanitation, shelter and to protect women and girls.