( CNN ) -- Seattle could see one of its largest snowfalls since the 1940s as twin winter storms move over the Pacific Northwest , according to the National Weather Service . Between 5 and 10 inches of snow could hit the Seattle-Tacoma area Wednesday , said Dustin Guy , a meteorologist at the weather service 's Seattle office . Precipitation moving in from the south and west is combining with cold air moving south from Canada to create the heavy snowfall , Guy said . If snowfall amounts top 7 inches , the winter weather event will rank among Seattle 's 10 worst since the early 1940s , Guy said . High-wind warnings were in effect along the coast , where winds could gust to hurricane force -- knocking down trees and causing power outages , said CNN meteorologist Taylor Ward . Wednesday 's snowfall in Seattle may equal its annual average , Ward said . Mountainous areas of the Pacific Northwest will see even more snow , with the largest accumulations on the eastern slopes of the Cascades , according to the weather service . Significant snowfall is expected across southern Washington , northwest Oregon and into western Idaho . Portland could see about 3 inches , according to Ward . From late Tuesday through early Thursday , 2 feet to 3.5 feet of snow is forecast for the mountains east of Seattle , Guy said . Mount Rainier could see 10 feet of snow by Friday . The first storm moved into the area Monday and Tuesday . The second and stronger storm was forecast to hit Wednesday into Thursday . `` It 's pretty big when you get back-to-back storms like that , '' weather service meteorologist Roger Cloutier said . Scattered areas near Easton , Washington , along Interstate 90 in the Cascade Mountains 55 miles east of Seattle , have already received 32 inches of snow , Cloutier said . The snowfall extends south into Oregon , with as much as 18 inches forecast for the Bend area . CNN affiliate KTVZ-TV in Bend said an earlier round of snow over the weekend gave a boost to local ski resorts but also created treacherous driving conditions that left at least one motorist dead . Those conditions were expected to worsen . Winter storm warnings were in effect across the region . `` Expect extreme travel difficulties to develop on Wednesday , '' the weather service said , advising those who must take to the roads during the storm to carry a flashlight , blankets and extra food and water . The Washington State Department of Transportation said 1,250 workers will use nearly 500 pieces of equipment statewide to treat and plow roadways . CNN affiliate KING-TV reported that Seattle Public Schools opted to close all schools two hours early . The heavy snowfall will be followed by rain , which could produce ponding water and urban flooding , Guy said . `` It 's just gon na be a mess all around , '' he said of the coming few days in the Seattle area . Cloutier said even though computer models are trending colder and colder for the coming days , the heavy snow will eventually pose a flooding threat . `` When the snow does finally melt , you can almost guarantee there will be some flooding somewhere , '' he said .
NEW : Seattle prepares for significant snowfall . Storms could be among area 's 10 worst since 1940s . Up to 3.5 feet of snow in Cascade Mountains forecast . Comment: The storm is moving from the west, so it will hit us on Friday or Saturday and then move out over the weekend.