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.
Two mid-level troughs with associated surface lows are forecast to bring widespread precipitation to California between February 14 and 19, 2025. The first system is forecast to begin affecting the state on February 14–15, followed by a second trough deepening offshore from February 16–17. Snowfall totals over the Sierra Nevada could exceed 60 cm (24 inches), while rainfall totals of 25–50 mm (1–2 inches) are forecast across much of the state during the initial 72-hour period.
A strong atmospheric river is forecast to impact California from December 23 to 27, 2025, bringing widespread heavy rainfall, flash flooding, and high-elevation snow. The system is expected to produce 250 to 500 mm (10–20 inches) of precipitation in parts of the Sierra Nevada and 150 to 300 mm (6–12 inches) in the Coast and Transverse Ranges. The National Weather Service has issued high-risk alerts for flash flooding across southern California and moderate winter storm impacts over the Sierra Nevada.
Downtown San Francisco reached only 10°C (50°F) on Sunday, November 30, 2025 – the city’s lowest daily maximum for the date in records dating back to 1874. The unseasonably cold conditions developed under a persistent marine layer and stagnant air pattern, keeping the city unusually cold for late autumn.
A mid-level trough deepening along the US West Coast is forecast to evolve into a cutoff low over Southern California and a potential atmospheric river (AR) over the Pacific Northwest between November 19 and 24, 2025.
A Winter Storm Warning and a Freeze Watch is in effect for parts of California and Nevada through early Wednesday, November 19, 2025.
Heavy snow and gusts to about 65 km/h (40 mph) are forecast for the West Slope Northern Sierra Nevada and Western Plumas County/Lassen Park in California on Monday, November 17, 2025, with a Winter Weather Advisory in effect until 16:00 PST. A brief break is forecast for Tuesday and Wednesday, followed by increased chances for rain and snow showers on Thursday, November 20.
At least 6 fatalities have been reported as of Sunday, November 16, 2025, as a powerful atmospheric river continues to impact California. With heavy rainfall of up to 200 mm (8 inches) being forecast, authorities are preparing for the threat of flash floods, landslides, debris flows across the state.
A strengthening low-pressure system offshore is forecast to spread heavy precipitation and mountain snow across the Sierra Nevada from Thursday, November 13 through November 15, 2025. Winter Weather Advisories are in effect for the Eastern Sierra Slopes, Greater Lake Tahoe Area and the West Slope Northern Sierra Nevada, with snow levels forecast to drop into November 14 and accumulations reaching 30–60 cm (12–18 inches) at the highest peaks.
Interior Mendocino and Lake counties are under a Flood Watch from late Wednesday, November 12, through Thursday morning, November 13, 2025, as 50–75 mm (2–3 inches) of rain is forecast within several hours. Marine Storm and Gale Warnings are also in effect offshore, where winds up to 95 km/h (60 mph) and seas up to 8 m (27 feet) are expected.
