* WHAT...Heavy snow expected. Additional snow accumulations of 4 to 8 inches above 4000 feet with locally higher amounts along the Cascade crest. Winds gusting as high as 45 mph. * WHERE...East Slopes of the Oregon Cascades. * WHEN...Until 5 AM PDT Thursday. * IMPACTS...Travel could be difficult due to periods of moderate to heavy snow. Gusty winds could bring down tree branches. * ADDITIONAL DETAILS...Lighter snowfall is forecast below 4000 feet along US 97, US 26, and US 20. Steady snowfall this morning will turn over to snow showers this afternoon.