The powerful March storms that drenched Hawaii produced more than 2 trillion gallons of rain and pushed precipitation levels to as much as 3,000% above normal in a 14-day period for this time of year.
During this heat wave, "not only are daily temperature records likely to be broken across the region, but even the high temperature records for any day in the entire month of March," the National Weather Service said in a Tuesday morning forecast.
Even though the evidence is still early, this could be a very significant event in 2026 and lingering into 2027. Its function in the global earth system is to release heat from the deeper oceans that has been temporarily stored there. El Nino allows that subducted heat to be unearthed.
The shower activity is going to continue throughout the day, National Weather Service meteorologist Lamont Bain said. As it pertains to thunderstorm risk, there's probably a 10-to-15 percent chance. There is a lot of instability between the upper low pressure and the lower air. That upper low is going to spin out there and not move much, and that's why the rain showers are going to be scattered throughout the day and why the best chances for thunder are out over the ocean.
Two waves drive the bulk of the snow, with a relatively higher snow level and denser snow early, followed by a colder surge that improves powder quality and brings the strongest winds. Expect long stretches of snowfall for the Sierra with only brief lulls, plus periods of wind-driven, low-visibility skiing on upper mountain. Southern California gets meaningful mountain snow as well, but snow levels are a bigger deal there and the best accumulation favors higher terrain.
Sun night (02/15) through Tue night (02/17) is the core punch, and many Sierra mountains can stack 20″-50″ in that window as snow levels crash. Expect a lighter start Sunday night, then snowfall rates ramp up hard Monday night into Tuesday with widespread coverage across Tahoe, the central Sierra, and down into Mammoth. Snow levels begin around 5,000 to 5,500 feet early, then fall into the 1,500 to 2,500-foot range by Tuesday and Tuesday night, which helps keep even lower terrain in play for all-snow.
It's turned into an unusually dry winter for Northern California, and that pattern, thanks to a ridge of high pressure, is going to continue for at least the first 10 days of February. As the Chronicle meteorology team tells us, the dry and balmy conditions will be with us through Super Bowl Weekend and beyond, continuing a pattern that has left the Sierra snowpack mighty low.
While cold-stunned iguanas fall from trees in Florida and videos circulate of frozen "exploding" trees in the Northeast, Southern California is working up a sweat. A midwinter heat wave has descended on much of the state and is expected to spike temperatures as much as 20 degrees above normal in the coming week. The summer-like heat is thanks to a ridge of high pressure lingering high in the atmosphere that extends through the San Francisco Bay Area and into the Pacific Northwest.
The pattern change began Monday when the barometric pressure surrounding the region started to fall gradually. That increase in low pressure is coming from the southwest and the air is flowing north, opposite of many winter low-pressure systems that dip in from the Pacific Northwest. As a result, light but steady rain is expected to start in Monterey County and the Central Coast late Tuesday morning. The rain is expected to reach the region closer to San Francisco sometime Tuesday night, Murdock said.
