A methyl methacrylate leak from a storage tank at GKN Aerospace in Garden Grove, California, was reported at around 15:30 LT (22:30 UTC) on May 21, 2026, prompting evacuation orders for about 40 000 people across northwestern Orange County.
The Sandy Fire, discovered at around 10:50 local time (LT) on May 18, 2026, has burned more than 526 ha (1 300 acres) across Simi Valley in Ventura County, California, forcing mandatory evacuations for more than 10 000 homes and triggering warnings for thousands more as firefighters battle rapid fire spread driven by dry and windy conditions.
A record-breaking wildfire burning on California’s Santa Rosa Island has scorched more than 5 900 ha (14 600 acres) and continues to threaten rare Torrey pine trees, endangered plant species, and historic structures.
Hundreds of earthquakes struck the Brawley area of Imperial County, California, from May 9 to 11, 2026, including the strongest reported M4.7 event at 07:10 UTC on May 10. The swarm caused infrastructure damage, including water line breaks and road damage.
A rare tornado event occurred in California after three tornadoes touched down in Fresno and Merced counties on April 21, 2026. This was the third time since 1955 that three or more tornadoes have touched down in the National Weather Service (NWS) Hanford Office’s jurisdiction.
Heavy snow and strong winds are forecast to impact the Sierra Nevada, California, from April 21 to April 22, 2026, as a Pacific storm system moves inland, bringing significant snowfall to elevations above 2 100 m (7 000 feet). Authorities warn that travel through major mountain passes could become very difficult to impossible due to snow-covered roads and reduced visibility.
A cluster of underground pipe failures has been detected in San Ramon and surrounding East Bay communities, California, following a sequence of earthquake swarms active in the area since 2025. The incidents include fractured water and sewer lines, often identified only after prolonged leakage periods and abnormal water usage. Experts consider ground movement associated with recent seismic activity as a possible contributing factor, although causation has not been confirmed.
A tornado briefly touched down in a remote grassland area of southeastern Tehama County, California, at 14:05 PDT (21:05 UTC) on April 12, 2026, about 6.4 km (4 miles) southeast of Vina. The touchdown lasted about 1 minute and caused no reported injuries or structural damage, according to NWS Sacramento.
A historic March heat event affected the U.S. Southwest on March 19 and 20, 2026, setting a new March temperature record in Las Vegas, Nevada, and a new highest March temperature ever recorded in the United States near Martinez Lake, Arizona. Multiple daily and monthly records were also broken across parts of Nevada, California, and Arizona, while authorities in Phoenix closed some hiking trails because of heat risk.
An anomalously early-season heatwave intensified across the western United States on March 18, 2026, with Extreme Heat Warnings in effect for parts of the Desert Southwest and temperatures forecast to expand east into the Rockies and Great Plains by March 20. Highs are expected to reach 40–44°C (104–112°F) in the hottest desert regions, with numerous daily and some monthly March records likely to be broken.
