SAN FRANCISCO (CBS SF) — A potent winter cold front continued its march toward Northern California Monday, triggering warnings of torrential rainfall and flooded roadways by mid-week.

The National Weather Service said the front would arrive in the North Bay sometime around mid-day Wednesday and then march southward through the evening.

“Heavy rain will develop across the North Bay first and then spread southward, wreaking havoc on the Wednesday afternoon/evening commute,” forecasters warned.

The storm will unleash its full fury on the North Bay and Santa Cruz Mountains, but the rain totals will be significant elsewhere.

“On average 3-6 inches of rain will be possible in the hills with 1-3 inches in the lower elevations by Thursday morning with much of the rain falling,” the weather service warned.

The rains will also trigger urban and small stream flooding as it runs off already saturated hills.

“We are predicting a burst of heavier rain to arrive between 4 and 10 p.m. Wednesday, and during that six-hour window more than an inch of rain could fall,” said KPIX 5 meteorologist Paul Deanno. “That’ll be more than enough for street and highway flooding issues.”

Strong winds will also accompany the front, triggering a high wind watch for the Bay Area beginning on Wednesday afternoon. A high wind watch is in effect for Wednesday evening for the entire Bay Area, including the urban core,” said Deanno. “Winds will likely reach 25-40 mph with higher gusts.

“Damaging winds will blow down trees and power lines,” the weather service warned. “Widespread power outages are possible.”

Two less potent storms will move through the area Monday night and on Tuesday.

“A weak storm moves in later Monday into Monday night bringing areas of light precipitation,” forecasters said. “A second system will be wetter and move into the region Tuesday into early Wednesday.”