• Record-breaking King Tides flood San Francisco Bay Area and Northern California coast, U.S.

    Record-breaking King Tides struck the San Francisco Bay Area and parts of the Northern California coast on Friday and Saturday, January 2-3, 2026, causing widespread coastal flooding across multiple counties. Tide gauges across the region recorded water levels up to 0.76 m (2.5 feet) above normal, breaking multiple records and prompting road closures, flood warnings, and emergency advisories.

  • Polar Vortex disruption expected after January stratospheric warming

    A Sudden Stratospheric Warming (SSW) event evolving over the Arctic through mid-January 2026 is forecast to weaken and displace the Polar Vortex, according to ECMWF and NOAA extended-range guidance. The disturbance is expected to propagate downward over the following weeks, raising the probability of Arctic air outbreaks and colder-than-normal conditions in parts of North America and Europe during the second half of January 2026.

  • Alberta clipper reinforces lake-effect snow as heavy rain targets southern California into the New Year

    A surge of Arctic air, reinforced lake-effect snowfall, and an atmospheric river are forecast to affect large portions of the United States from December 31, 2025, into January 2, 2026. Heavy snow is expected downwind of the Great Lakes and across parts of the Northeast, while southern California faces a flash flood risk as an atmospheric river moves onshore around New Year’s Day.

  • Subtropical moisture and re-intensified atmospheric river to impact California through New Year’s weekend

    A surge of subtropical moisture is forecast to bring moderate to heavy rain to southern and central California on Wednesday, December 31, 2025, with rain spreading north on Thursday, January 1, 2026. A stronger system with a re-intensified atmospheric river is expected to make landfall early Friday, January 2, bringing heavier precipitation along the northern and central California coast.