The storm system that has soaked Northern California since Wednesday is expected to pack its biggest punch today.

"This is Round 3 and the most powerful of the storms," said Johnnie Powell, a forecaster for the National Weather Service in Sacramento, on Saturday. "Expect 3 inches of rain through Sunday evening."

As of late Saturday, more than 21/2 inches of rain had been recorded at Sacramento Executive Airport in the preceding 72 hours.

A flood watch remains in effect for the Sacramento Valley through this afternoon. The region is also under a wind advisory expected to last through this afternoon, with southerly winds from 15 to 25 mph – and gusts up to 40 mph – likely.

Rivers in the region will be vulnerable to flooding in the Sacramento Valley, although most are below flood stage. The upper Sacramento River is expected to reach flood stage at a number of locations today and Monday, the weather service reported.

In the Sierra, damaging wind gusts and several feet of snow are forecast, with major flood warnings in effect for the Truckee River near Truckee, and some tributaries in Nevada and Placer counties.

The National Weather Service in Reno reports that a flood watch for the Truckee area is in effect through Monday morning.

People living along small creeks and streams throughout the Tahoe basin should prepare for flooding as well and have a plan to move to higher ground if it occurs, the weather service advised.

Officials in Placer and Nevada counties are warning residents living in low-lying areas to take precautions and monitor the conditions closely through media outlets and the Truckee website, www.townoftruckee.com.

The weather service is predicting the Truckee River will reach near 8 feet between 3 a.m. and 3 p.m. today along Highway 89 and near the Placer/Nevada County line.

The rainy weather has left its mark in the Sacramento area.

On Saturday, some drywall came down about 3 p.m. over the entry of the JC Penney store in the Westfield Galleria in Roseville.

"When sheetrock gets wet it comes down and did cause one minor injury," said Rich Thickens, battalion chief with the Roseville Fire Department.

The victim was taken to a local hospital. The damaged entrance will be closed for repair, and the rest of the Galleria remains open, said Westfield officials.

Wind and rain also caused the downing of trees, including the collapse of a century-old heritage oak in the Briggs Ranch subdivision of Folsom.

A 75-foot oak sheared off near the base Friday night and crashed into the home of Folsom resident Mike Pilat.

"It sounded like a freight train," said Pilat, who owns the property in the 100 block of Skidmore Court. "This is a big boy that fell here."

TRUCKEE PLANS EVACUATION CENTERS

The American Red Cross is working with local emergency agencies to set up an evacuation center in Truckee in case the Truckee River floods this morning.

According to a Truckee Police Department news release, the evacuation center will be in the Administration Building of the Tahoe Truckee Unified School District, 11603 Donner Pass Road.

The center is scheduled to open at 6 a.m. and remain open as long as it is needed.

To get updated recorded information on the evacuation center, call a toll-free number set up by the Nevada County Office of Emergency Services: (855) 212-1866.

The center will serve as an overnight shelter if there is a need.

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