A weekend of heavy rains and flooding left destruction across large areas of northern India, killing at least 23 people and causing landslides and flash floods that washed away bridges and buildings, officials said.
Most of the deaths over the weekend appear to have been in the Himalayan state of Himachal Pradesh, which received more than 10 times its average rainfall for that time of year. The wreckage from the deluge forced the authorities there to close schools and advise residents to leave their homes only if necessary. Dozens of people in total have been killed in the state since the monsoon season began in June.
Torrential rain continued to lash many states on Monday afternoon, including the capital Delhi, where roads in several areas were submerged in knee-deep water and courtrooms had to be suspended or switched online, away from flooded courthouses.
In recent years, India has often experienced extreme weather patterns, including record heat waves and heavy flooding in monsoon season. In the case of the floods, in addition to the stress on everyday Indians, farmers complained about the devastating effect on crops as the rains became more unpredictable and damaging.
RK Jenamani, who works for the India Meteorological Department in New Delhi, said the confluence of cyclonic storms called western disturbances with the monsoon season was behind the current downpour, the heaviest in decades. More rain across large parts of northern India is forecast for the next few days.
“The rain is several times more than normal,” Mr. Jenamani said. “For example, in Himachal Pradesh, the normal rainfall would have been about eight millimeters, but it was 103.4 millimeters on Sunday.” Eight millimeters is less than half an inch; 103.4 millimeters is approximately four inches.
Video film from Himachal Pradesh, a popular tourist destination, showed flash floods washing away homes, and rescue workers struggling to bring trapped people to safety. Jagat Singh Negi, the state’s horticulture minister, said at least 20 people had died in rain-related incidents there over the past two days, bringing the total to more than 70 who have been killed since June 24 after floods engulfed entire villages, triggering landslides. and blocking hundreds of roads.
Some of the heaviest rains in decades also lashed the Delhi region, according to the India Meteorological Department. The rains flooded homes and streets, killing at least three people, Delhi fire officials said.
Government workers used pumps in many places to drain water from streets, with residents wading through knee-deep water. Delhi received 153 millimeters of rain on Sunday, the highest rainfall in a single day in July in 40 years, the meteorological department said.
In the state of Punjab, the Indian government deployed hundreds of soldiers to help prevent the breach of swollen water channels and to help rescue some 2,000 students stranded at a university. Streets remained under water, and in many places, residents used ropes to cross from one side of the road to the other.
The arrival of the monsoon in northern India in recent years has increasingly caused damage and deaths. But the effects of climate change have rarely seemed as severe as they were over the weekend in some areas straddling the towering Himalayan range, which stretches 1,500 miles across Asia, from Pakistan to Bhutan.
Some regions in India, including the Ladakh desert and around the nearby city of Kargil, received three inches of unseasonal snowfall. Residents said they had never seen snow in the month of July before.
On Monday, the downpour continued in some states as local authorities issued alerts asking residents to stay indoors.
Atishi Marlena, a minister in the Delhi government, said that the Yamuna River, a tributary of the Ganges that runs through New Delhi, is expected to reach a dangerous level and that the government is setting up rescue boats in areas closer to the waterway.
“Public announcements for people living in flood plains have started,” she added.
Among the infrastructure damaged by heavy rains and landslides were highways and bridges in the states of Himachal Pradesh, Uttarakhand, and Jammu and Kashmir that were built to help lift millions of people in remote districts out of poverty. Most of this destruction was in Himachal Pradesh, where entire stretches of roads were destroyed and dozens of buildings collapsed and were washed away by flash floods.
Mr. Negi, the Himachal Pradesh minister, said the level of damage caused by the rain in some areas of his state was dire and unprecedented, adding that time was needed to fully assess.
“It’s very scary,” he said in a phone call. “But we’re trying everything to keep people safe.”