Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 357 AM EDT Wed Apr 19 2017 Valid 12Z Wed Apr 19 2017 - 12Z Fri Apr 21 2017 ...Heavy rainfall will be possible along a frontal boundary as it progresses from the Central U.S. into the Northeast Wednesday and Thursday... ...Strong to severe thunderstorms are possible today for portions of the Central Plains and middle to upper Mississippi Valley... ...Rain and mountain snow returns to the Northwest today ... The Pacific Northwest will return to a wet pattern today, which will continue for a few days. Rain and mountain snow will expand beyond the Cascades by late tonight, reaching the northern and central portions of the Rockies by Thursday morning as a frontal boundary passes eastward. Another frontal system, spanning from the Great Lakes region to the Desert Southwest will track east through the central and eastern states. Embedded areas of heavy to excessive rainfall may develop along the boundary as it passes through the Central Plains and continues eastward into the Ohio Valley and the Northeast. Additionally, strong to severe thunderstorm initiation will be favorable along this boundary today. The Storm Prediction Center depicts a slight risk area from central Kansas to southern Wisconsin and northern Illinois, with an enhanced area over eastern Iowa. Cold air filtering into the Upper Mississippi valley and Great Lakes region will allow for rain to switch over to mostly snow by Thursday afternoon and beyond. Showers and thunderstorms may also be possible across the Southeast and southern Mid-Atlantic states on today near a frontal boundary lingering across the region. Campbell Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php