Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 408 PM EDT Thu Aug 10 2017 Valid 00Z Fri Aug 11 2017 - 00Z Sun Aug 13 2017 ...Heavy rain and strong to severe thunderstorms will be possible over portions of the Central Plains... ...Widespread shower and thunderstorm activity is expected over the eastern third of the Nation... ...A cooling trend is in store for the Northwest this weekend... A frontal boundary pressing southward into the Central Plains Thursday evening is expected to stall and linger across the region Friday and Saturday. Anomalous moisture along the boundary should fuel developing convection and heighten the risk for organized areas of heavy rain and strong to severe thunderstorms from southeastern Colorado into Kansas, the Texas Panhandle, and much of Oklahoma. Farther north, showers and thunderstorms will also be possible across the Northern to Central High Plains Friday into Saturday as the northwestern extent of the stalled boundary remains banked against the eastern slopes of the Rockies and shortwave energy begins to drop through the north central U.S.. An abundance of moisture and instability surging northward through the eastern third of the Nation, ahead of an approaching cold front, should foster widespread shower and thunderstorm activity from the Southeast to the Mid-Atlantic States, and eventually portions of the Northeast Friday and Saturday. Activity should be mainly scattered in nature, but locally heavy rainfall will be possible. Another day of above normal temperatures are expected across the Northwest on Friday, but then a cooling trend is expected as a once persistent upper ridge across the region slides eastward this weekend. Meanwhile, broad troughing and precipitation should keep daytime temperatures below normal for much of the central and eastern U.S.. Gerhardt Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php