Overview

• Rain is forecast from Monday through Wednesday with at least an inch across the Bay Area and 2 to 3 inches possible in higher terrain, according to the National Weather Service.
• The NWS has issued a winter storm watch for the west slopes of the northern Sierra Nevada for the same period, with 2 to 12 inches of snow north of Highway 50 and 1 to 2 feet south of Highway 50 above about 6,500 feet.
• Thunderstorms are a slight possibility and there is at least a 5% chance of localized flash flooding in parts of Northern California during the event.
• Forecasters warn this is the first widespread wetting rain of the season, raising the risk of crashes due to slick roads from oil buildup and urging extra caution while driving.
• Some weather teams report the system could tap remnant moisture from Typhoon Halong even as federal scientists confirm La Niña, which does not preclude early-season storms in Northern California.