SAN FRANCISCO (CBS SF) — Mother Nature was preparing a spring surprise for the Bay Area Tuesday, a series of winter-like storms that will dump as much as 200 percent of the normal precipitation for May by the time they move on next week.

Over the next week, a low pressure system from the Gulf of Alaska will send waves of stormy weather through the Bay Area and over the Sierra. Forecasters said as much as 2 inches could fall in the North Bay and the Santa Cruz Mountains with 5-10 inches of snow in the Sierra.

“The characteristics of the passing Wed/Thur system look more like a winter storm than a May storm,” the national weather service said.

While the morning commute on Wednesday by be a little wet north of the Golden Gate Bridge, the evening commute could be very challenging with steady rain in the forecast for most of the Bay Area.

“The evening commute on Wednesday could be a mess for San Francisco northward,” the weather service warned.

The Wednesday-Thursday weather system is just the first predicted for the next week. Rain chances will gradually diminish Thursday night into Friday, forecasters said, as the upper low exits to the east and ridging develops.

The drier weather will be short-lived on Friday and early Saturday as another system will bring additional rainfall this weekend. Another break in the action was possible early Monday, forecasters said, before yet another system takes aim at the Bay Area bringing even more rainfall.

“The rainfall over the next 5-7 days is definitely above normal,” the national weather service said. “Parts of the region could see more than the monthly normal (rainfall) in just a few days. When it`s all said and done the one outcome that seems most certain is slowing the onset of wildfire season.”

In the mountains, a winter storm watch goes into effect from Wednesday evening through Thursday night above 5,000 feet.

“Impacts to Sierra passes were not expected until Thursday evening into Friday morning when snow levels fall to near 6000 feet,” the weather service said. “Sierra passes from Donner to Carson Pass could see 2-7″ of snowfall by Friday morning, but the heaviest snowfall totals are expected on mountain top locations above 8500 feet mainly across Mono County where 10-18″ is possible.”