GLOBAL WEATHER HIGHLIGHTS

DECEMBER 2025

ASIA

Families stranded on their rooftops—homes buried by fast-flowing mud. Jagged brown craters scarred lush green hillsides. The scenes are the result of a series of cyclones and storms in a heavy monsoon season that have struck Asia with torrential rains, gutting essential infrastructure and reshaping landscapes. The violent weather has killed at least 1,200 people in the past week and forced a million to flee without knowing whether their homes will still be standing when they go back. The fallout marks a grim escalation in deadly weather across the region, which has been exacerbated by the blanket of carbon pollution heating the planet. A review by the Intergovernmental Panel on Climate Change (IPCC) projected that South and Southeast Asia will suffer heavier rain as temperatures rise, with a “large increase” in flood frequency striking monsoon regions. Roxy Koll, a climate scientist at the Indian Institute of Tropical Meteorology and coauthor of the latest IPCC report, said the cyclones’ behavior had changed more than their number this season. “They are wetter and more destructive because the background climate has shifted,” he said. “Water, not wind, is now the main driver of disaster.”Natural weather patterns, including a La Niña cycle and a negative Indian Ocean dipole, have helped to create conditions for the storms to form. Scientists have not determined the extent to which planet-heating pollution contributed to the death toll, which continues to rise with floodwaters, but they have long established that warmer air holds more moisture – about 7% per degree Celsius. The extra water, together with the increase in energy from hotter oceans, leads to the formation of storms that pack far more punch. “Across south and south-east Asia, storms this season have been carrying extraordinary amounts of moisture,” said Koll. “A warmer ocean and atmosphere are loading these systems with water, so even moderate cyclones now unleash rainfall that overwhelms rivers, destabilizes slopes and triggers cascading disasters.

INDONESIA

The number of people killed by floods and landslides on Indonesia’s Sumatra island rose to 708 on Tuesday, the country’s disaster agency said, with 504 people missing. The toll was a sharp increase from the 604 dead reported by the agency on Monday. Heavy monsoon rains and tropical cyclones have devastated parts of Asia this week, including Indonesia, Sri Lanka, and southern Thailand, killing more than 1,300 people across the region, destroying infrastructure, and inundating towns. About 3.2 million people have been affected and 2,600 have been injured in Indonesia alone. A million people have been evacuated from high-risk areas. It was earlier reported that 753 people had died, but the figure was revised down to 708 on Tuesday evening.

Aid workers and response teams are racing to reach survivors, but have been hampered by blocked roads and broken bridges. Some areas, including Tapanuli Tengah in North Sumatra and Agam in Aceh, were inaccessible by road, according to UNICEF.  In Aceh, one of the hardest-hit areas, markets are running out of rice, vegetables, and other essentials, and prices have tripled, according to Islamic Relief, which is sending 12 tons of emergency food aid. “Communities across Aceh are at severe risk of food shortages and hunger if supply lines are not re-established in the next seven days,” the charity said. The Indonesian government said on Monday it was sending 34,000 tons of rice and 6.8m liters of cooking oil to Aceh, as well as the provinces of North Sumatra and West Sumatra.

UNITED STATES

A heavy rain and wind storm, carried by an atmospheric river from the Pacific, has been blamed for a third death in southern California as flooding, road closures, and debris flows are reported across the region. A flood watch was also extended through Thursday for almost all of the area, as more than 11 inches of rainfall was measured in some parts of Los Angeles County as of Wednesday night, and evacuation warnings were issued for mountain communities in San Bernardino County. “There is a moderate risk of excessive rainfall over parts of southern California,” the US Weather Prediction Center said in a forecast early on Thursday. “Numerous flash flooding events are possible. In addition, many streams may flood, potentially affecting larger rivers.”  On Wednesday, California’s governor, Gavin Newsom, declared a state of emergency in Los Angeles County and other southern California counties, citing flooding and landslides risks in areas affected by last year’s wildfires. The Los Angeles mayor, Karen Bass, declared a local emergency. “I am urging all Angelenos to stay safe and be extremely careful on the roads if you absolutely must travel. Please do not take this storm lightly – follow official guidance, plan ahead, and sign up for emergency alerts,” she said.

AUSTRALIA

Bushfires have been ravaging Australia, with more than 50 burning throughout New South Wales, destroying homes and causing at least one death. Nine blazes remained out of control on Monday as flames ripped through homes and critical infrastructure. Scorching temperatures – peaking at 41C in Koolewong – combined with fierce, erratic winds to spread the fires rapidly and made them harder to control.  On Sunday night, an Australian firefighter was killed after a tree fell on him while he worked on a fire near Bulahdelah, about 150 miles (250km) north of Sydney. The blaze scorched 3,500 hectares (8,600 acres) and destroyed four homes over the weekend. NSW, one of Australia’s most fire-prone regions, is particularly vulnerable because of its hot, dry climate and vast eucalyptus forests, which shed oils that become highly flammable. Farther south, Tasmania faced its own emergency, with a fast-moving 700-hectare fire at Dolphin Sands destroying 19 homes and damaging at least 40 more, leaving coastal communities reeling. Authorities warn the heightened bushfire threat is being fuelled by rising temperatures and a dangerous build-up of vegetation. Previous years of La Niña weather systems had unusually wet summers, resulting in dense growth across forests and grasslands. However, recent months of below-average rainfall have rapidly dried that vegetation, turning it into abundant, volatile fuel. With the season already labelled as “high risk”, many fear this could be Australia’s most dangerous summer since the “black summer” fires of 2019-20. Meanwhile, the US state of Washington is bracing for dangerous flooding as an atmospheric river continues to drench the Pacific north-west. Authorities issued immediate evacuation orders for about 100,000 residents on Thursday as relentless rain pummeled the region for another day. In just 24 hours, north-west Washington has been hit with 120-205mm of rainfall, with flooding from the Cascade Foothills to Puget Sound expected to worsen through Friday. Rivers across the state are surging towards their most severe flood classifications, with several threatening to break historic records. The Skagit River, one of Washington’s largest, is forecast to crest 6ft above its previous peak.