The potential for a large midweek storm has vanished from the Bay Area forecast. But just as the midweek storm has trended much drier, Monday and Tuesday now look much more active, with rain, wind, thunderstorms and several feet of mountain snow across Northern California.
- Live storm map : See where rain is hitting California and Bay Area
Here’s what to expect this week.
Downpours, thunderstorms Monday and Tuesday
A low-pressure system in the eastern Pacific Ocean is expected to inch toward the Oregon coast Monday and bring widespread rain and snow with it to the West Coast.
This system will have surpassed peak maturity as it nears the coast, meaning it won’t have well-defined warm and cold fronts, rather an occluded front . These types of systems, with a mix of warm, moist air and cold, dry air, tend to support the development of thunderstorms, especially during spring. Both Monday and Tuesday present a chance of thunderstorms across Northern California, most likely during the afternoons in the Sacramento Valley and the delta.
Supporting Monday’s thunderstorm risk is a near record-strong jet stream over Northern California. This jet stream will induce strong wind shear, changing wind speed and directions in the atmosphere, a necessary ingredient for long-lived thunderstorms.
These storm winds will support heavy snow in the Sierra Nevada, where up to 5 feet could accumulate through Tuesday. Winter storm warnings are in effect across Donner Pass and in the Tahoe basin…