Walking to his local mosque in northern Pakistan, Abdul Samad cast worried looks at a stream he had never seen so agitated and choked with debris. When he stepped outside again 10 minutes later, the mountain village that was his lifelong home had been nearly erased.

Swollen by pummeling rainfall, the stream had turned into a roaring torrent that swept mud, rocks and fallen trees through the village of Beshonai on Friday, crushing, burying or washing away everything in its path. Out of 210 homes, only 25 remain standing, according to local officials.

“Houses, fields of maize, everything was gone. All I saw were boulders upon boulders,” said Mr. Samad, an imam in his mid 40s. His wife and daughter were swept away with the family home and killed. His mother’s body was not found until Monday, three miles downstream.

The monsoon season, once revered as a source of life and renewal, has brought death and devastation across large parts of Pakistan, a South Asian nation of 250 million people. Monsoons have killed more than 700 people nationwide since the season began in late June. This increasingly frequent pattern is forcing Pakistan to reckon with a new reality: Destruction brought by extreme weather has become the norm, not the exception.

In northern Pakistan, floods cascaded down mountain slopes last week, eradicating entire villages. Boulders and pine trees smashed through houses. Mud swallowed whole families.

“What we were used to in Pakistan has changed, and for now it is too much,” said Dr. Maryam Ibrahim, an environmental expert and professor of environmental studies at the Lahore University of Management Sciences. “This phenomenon of streams or rivers gradually swelling, in a slow process that would give time for people to evacuate, is gone.”

Mr. Samad said he survived only because the mosque had been built on higher ground. His son and his nephew were pulled to safety by neighbors.

As he led mourning prayers on Monday and paid a last tribute to his mother, he implored God to have mercy on the community.

Beshonai, in Buner district, is one of dozens of northern villages devastated by rains so heavy and sudden that flash flooding caught officials and communities off guard.

The highest toll has been recorded in Khyber Pakhtunkhwa, a province bordering Afghanistan, where flooding has killed at least 365 people since last Thursday. Buner district suffered the worst devastation, with at least 225 confirmed deaths.

Pakistan’s troubles redoubled on Tuesday, as floodwaters flowed southward, inundating more areas. The port city of Karachi, the country’s economic hub with more than 20 million people, was paralyzed, as residents waded through water that was shoulder-deep in some streets.

The floods are the most devastating Pakistan has endured since 2022, when record monsoon rains killed 1,700 people and submerged a third of the country.

Since then, Pakistan’s successive governments have campaigned for better access to international climate finance, as the country contributes less than 1 percent of the world’s greenhouse gas emissions but is one of the most vulnerable countries to climate change. The World Bank has estimated that Pakistan needs $43 billion on average every year until 2030 to mitigate the effects of global warming.

But in recent days, the country’s authorities have also faced growing criticism for not doing enough to save lives. Critics say they have let deforestation go unchecked, worsening the impact of floods, and have failed to create effective early warning systems.

Aisha Khan, the executive director at the Civil Society Coalition for Climate Change, a Pakistani nonprofit, said the worsening floods could have severe social and political consequences.

“If extreme weather keeps being an annual event, if it keeps hitting people so strongly and trapping them in a circle of perpetual poverty and misery, there will be upheaval,” she said.

Pakistan’s disaster management officials said they sent all the early warnings they could, including through a national app and communications to provincial authorities. But many areas have scant access to the internet, and in Beshonai and other places, people said the warnings from local mosques and police stations came late.

Officials also said that nothing could have prepared the country for what was unleashed on villages like Beshonai.

Watching a video of a cascade of mud devastating a northern village, Muhammad Idriss, an official at the national disaster management agency, asked, “What can the government do against this?”

At the agency’s operation center in Islamabad, the capital, on Tuesday, dozens of weather analysts and officials raced to assess the latest data and issue warnings of more rainfall. Surrounding them in a huge octagonal room, screens displaying videos and maps showed a country assailed by extreme weather — not only floods, but also extreme heat and wildfires.

A week ago, Beshonai, which has become a symbol of Pakistan’s suffering, had 4,000 people, many of them relying on money sent by relatives working abroad.

The few businesses that sustained the other residents are gone.

“This was once a bustling village,” said Shiraz Ali, a college student who was helping with rescue operations on Monday.

“How can anyone be normal in a place like this?”