Humans are on track to release so much greenhouse gas in less than three years that a key threshold for limiting global warming will be nearly unavoidable, according to a study to be released Thursday.

The report predicts that society will have emitted enough carbon dioxide by early 2028 that crossing an important long-term temperature boundary will be more likely than not. The scientists calculate that by that point there will be enough of the heat-trapping gas in the atmosphere to create a 50-50 chance or greater that the world will be locked in to 1.5 degrees Celsius (2.7 degrees Fahrenheit) of long-term warming since preindustrial times. That level of gas accumulation, which comes from the burning of fuels like gasoline, oil and coal, is sooner than the same group of 60 international scientists calculated in a study last year.

Summer will make a dramatic entrance in the U.S. this week with a heat dome that will bring stifling temperatures and uncomfortable humidity to millions.

The heat will be particularly worrisome this weekend across wide stretches of Nebraska, Illinois, Wisconsin and Iowa, where forecasters are warning of extreme temperature impacts.

South Africa was under a declared state of national disaster on Thursday as the death toll from floods caused by severe rains in the Eastern Cape region rose to 92.

The Eastern Cape government honored the victims of last week's floods with a provincial Day of Mourning and a memorial service at King Sabatha Dalindyebo Technical and Vocational Education and Training (TVET) College in Mthatha, one of the few schools whose infrastructure remained intact.

Rescue workers used rubber dinghies to evacuate people and deliver food and water Wednesday after floodwaters overwhelmed towns in southern China's Guangdong province.

About 30,000 people have been evacuated in Huaiji County after days of heavy rain, state broadcaster CCTV said.

Tropical storm Erick, bearing down on the southwestern coast of Mexico on the Pacific Ocean, strengthened into a hurricane Wednesday, the US National Hurricane Center said.

The hurricane is 255 kilometers (155 miles) from the town of Puerto Angel in the southern Mexican state of Oaxaca and is packing maximum sustained winds of 120 kilometers an hour (75 mph), the meteorological center said.

U.S. officials proposed Monday to protect the pangolin, a small, nocturnal mammal covered in scales, under the Endangered Species Act.

The pangolin is "the most trafficked mammal in the world" in large part for its scales, used in traditional Chinese medicine, and meat, according to the World Wildlife Fund.

Climate change has tripled the frequency of atmospheric wave events linked to extreme summer weather in the last 75 years and that may explain why long-range computer forecasts keep underestimating the surge in killer heat waves, droughts and floods, a new study says.

In the 1950s, Earth averaged about one extreme weather-inducing planetary wave event a summer, but now it is getting about three per summer, according to a study in Monday's Proceedings of the National Academy of Sciences. Planetary waves are connected to 2021's deadly and unprecedented Pacific Northwest heat wave, the 2010 Russian heatwave and Pakistan flooding and the 2003 killer European heatwave, the study said.

The death toll from weekend flooding in West Virginia rose to six as residents tried to clean up with the threat of more rain on the way.

At least two people remained missing in the state's northern panhandle after torrential downpours Saturday night, Gov. Patrick Morrisey said Monday. As much as 4 inches (10 centimeters) of rain fell in parts of Wheeling and Ohio County within 40 minutes. The dead included a 3-year-old child.

A fast-moving Hawaii brush fire fueled by fierce winds forced the evacuation of about 50 Maui residents on the opposite side of the same island where a devastating blaze killed over 100 people two years ago.

The fire started Sunday in a sparsely populated area with land set aside for Native Hawaiians.

Swiss authorities cleared a village in the country's east over a potential rockslide, three weeks after a mudslide submerged a vacated village in the southwest.

Residents of Brienz/Brinzauls, about 40 kilometers (25 miles) southwest of Davos, were being barred from entering the village because a rock mass on a plateau overhead has "accelerated so rapidly that it threatens to collapse," a statement from local officials said Monday.