Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 254 PM EST Wed Nov 04 2015 Valid 00Z Thu Nov 05 2015 - 00Z Sat Nov 07 2015 ...Heavy snow possible across the higher elevations of the central Rockies... ...Flash flooding possible across portions of the southern plains and Mississippi valley Thursday and Friday... ...Severe thunderstorms possible on Thursday for portions of the southern plains and Mississippi valley... A relatively strong low pressure system is moving across the Colorado Rockies today, and the surface low will move into the central High Plains by tonight. Moderate to heavy snow will continue to fall through tonight across the higher elevations of the Rockies before gradually beginning to taper off Thursday morning. As the system moves into the central/northern plains on Thursday, sufficient cold air will be in place on the northwestern edge of the precipitation area for rain to mix with or change to snow from portions of western Nebraska into parts of the Dakotas. Accumulations of snow across the northern plains will generally be light, in the range of 1 to 3 inches, although locally heavier amounts are possible. Farther south, numerous showers and thunderstorms are expected to develop on Thursday from the southern plains to the Midwest as warm, moist, and unstable air from the Gulf of Mexico streams northward ahead of the surface cold front. Heavy rainfall amounts of 1 to 3 inches are possible from portions east central Texas northeast to near the confluence of the Ohio and Mississippi rivers -- and flash flooding will be possible in these areas. The Storm Prediction Center is also forecasting a slight risk of severe thunderstorms on Thursday across portions of the southern plains and lower/middle Mississippi valley. By Thursday night the deepening surface low will move into southwestern Ontario, and will be near James Bay by early Friday morning. The cold front will sweep into the eastern U.S. on Friday, bringing scattered showers to the Northeast and Mid-Atlantic states. Meanwhile, the trailing end of the cold front will continue to bring numerous showers and thunderstorms from the eastern Ohio Valley into portions of the Southeast/Gulf Coast region. Flash flooding will be possible again on Friday from portions of the lower Mississippi valley to portions of the Tennessee valley. Another upper-level disturbance will move into the northwestern U.S. on Thursday, bringing another round of snow to the northern Intermountain states. This system will be moving relatively quickly, which will keep snowfall amounts in check -- but heavy snow will be possible at some of the higher elevations of the northern Intermountain states. Rain showers will also be possible across the lower elevations of the Pacific Northwest tonight into early Thursday in association with this system. Ryan Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php