Pakistan is one of the world’s top producers of red chile peppers, and the small town of Kunri is its red chile capital. Farmers dry their chiles the old-fashioned way, in the sun, and on market days, the dust is so overwhelming that the fiery air makes eyes water and throats burn.

But extreme weather — heat, floods, drought and the unpredictability and high costs that come with these events — is causing a way of life that has shaped generations of farmers to slowly disappear.

On a recent morning in Kunri, in southeastern Pakistan, Ahsan Ali Dars wandered his once-lush field of red chiles, now scarred by scorched crops, parched soil and empty patches. He scanned the sky for signs that the monsoon season was nearing, which might relieve the struggling plants stressed by months of extreme heat. But there wasn’t a drop of rain on the horizon, and within a few hours, the temperature would top 120 degrees.

Agriculture accounts for nearly a quarter of Pakistan’s economy and employs half of its labor force. But the South Asian country of more than 250 million people is among the world’s most vulnerable to climate change. Devastating floods in 2022 destroyed nearly 4.5 million acres of agricultural land — roughly the size of New Jersey — in an episode that many farmers in the provinces of Sindh and neighboring Punjab, Pakistan’s bread basket, say they are still reeling from.

Red chiles are among the worst-affected crops, and Pakistani farmers say that growing this staple of Pakistani cuisine has become a constant challenge. In recent years, unpredictable weather has brought heat waves and floods in a dizzying cycle, shattering crops and hitting small-scale traditional farmers especially hard, as the rising costs make it difficult for them to adapt.

These market days breathe life into Kunri, an otherwise sleepy town of 25,000 people in Sindh Province, about 70 miles west of the Indian border. The most affluent buyers at the market slalomed between the mounds on motorcycles, while day laborers trudged, their backs hunched over the weight of the chiles. On average, more than 200 metric tons of them were sold daily at that single market during the post-harvest season. The region accounts for more than 85 percent of Pakistan’s red chile production.

By the end of July, the monsoon finally brought the first raindrops to Mr. Dars’ fields. But with it will most likely come the risk of overwhelming rain, he noted.

“If there is too much rain, it will destroy the crop,” Mr. Dars said. “If there is no rain, that will also be destructive.”

“Whenever the government said it would open a center, nothing happened,” said Muhammad Saleem, a chile broker at the Kunri market.

Local officials acknowledge that they’re overwhelmed.

He said the Sindh government was taking steps to address some of those challenges, including the recent approval of a new chile market in Kunri with facilities like warehouses and auction grounds aimed at better protecting the harvest.

But faced with declining yields, higher fertilizer costs and persistent irrigation challenges, many farmers have begun to diversify.

This year, Mr. Dars decided to dedicate four acres of his field to 800 papaya plants. Still, he said, that no matter the crop, few may be able to hold up to extreme weather.

“It seems that nature is no longer on our side,” Mr. Dars said.