WASHINGTON — This summer’s weather was relentless and hellish, crowded with the type of record-smashing extremes that scientists have long warned about.

The season ends Wednesday, and not a moment too soon. Summer featured floods that killed hundreds of people and caused more than $50 billion in losses around the globe, from Louisiana and West Virginia to China, India, Europe, and the Sudan. Meanwhile, droughts parched croplands and wildfires burned from California to Canada to China and India. Toss in unrelenting record heat.

From June to August, there were at least 10 different weather disasters that each caused more than $1 billion in losses, according to insurance industry tallies. With summer weather now seemingly stretching from May to September, extreme weather in that span killed well more than 2,000 people. And that’s without a major hurricane hitting a big US city, although the Pacific had its share of deadly and costly storms, among them Typhoon Nepartak, which killed 111 people in Asia.

‘‘It is representing I think a notch up for the impacts we have had to deal with,’’ US National Weather Service director Louis Uccellini said. ‘‘We’ve experienced an increasing number and a disturbing number of weather extremes this summer.’’

While flooding made the news, the ‘‘sneaky’’ thing about the summer was heat that did not even ease at night, said Deke Arndt, climate monitoring chief at the federal National Centers for Environmental Information in Asheville, N.C.

When temperatures drop to below 72 at night it allows the body to recharge, plants to grow and air conditioners to be shut off. But this year that didn’t happen enough.

Associated Press