Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 343 AM EDT Fri Apr 15 2016 Valid 12Z Fri Apr 15 2016 - 12Z Sun Apr 17 2016 ...Heavy snow possible for portions of the Rockies and Front Range... ...Heavy rain and severe thunderstorms possible Friday for portions of the central and southern plains... High pressure over the eastern third of the U.S. will keep the progression of the low pressure crossing through the northern and central plains very slow this weekend. Ahead along and ahead of the cold front. Showers and thunderstorms are expected from the central Rockies to the northern High Plains ahead of the front, but will transition to mostly snow this afternoon and evening as cold air streams in the wake of the frontal passage. Snow will increase in intensity across the central Rockies as a surface low crosses the Four Corners region and will persist through Saturday as the low tracks eastward. This system will bring significant snow accumulations to the central Rockies and portions of the Front Range from Colorado to southeast Wyoming - amounts of 10 to 20 inches will be possible. Precipitation across the Northern high Plains will transition to a mix of rain and snow, or all snow by late tonight/early Saturday morning. Excessive rainfall will be possible for western portions of the Central Plains Saturday and Sunday, and in turn, will increase the threat for flash flooding. Scattered to numerous showers and thunderstorms are forecast for areas east of the frontal boundary in the central and southern plains. The warm and unstable environment will be conducive for strong to severe thunderstorms to develop over the next couple of days. The Storm Prediction Center has highlighted areas east of the southern and central Rockies as having a slight risk for severe storms today and Saturday, with south-central Texas as the favored area on Sunday.Periods of heavy rain will be possible as storms will likely develop and track for the same locations. A Moderate risk for excessive rain has been issued for the Texas panhandle and surrounding locations on Sunday. Accumulations of 4 to 7 inches will be possible through the weekend from Texas to Nebraska, with isolated higher amount possible. High pressure will dominate the weather pattern across the Mid-Atlantic and Northeast through Saturday, with dry conditions and temperatures near or slightly above average. Scattered showers and thunderstorms will persist in the Southeast along a lingering weak frontal boundary over the northern Gulf and the Florida Peninsula. Convection will diminish by Saturday as the upper-level low weakens. Campbell Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php