Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 500 PM EDT Sat Apr 26 2014 Valid 00Z Sun Apr 27 2014 - 00Z Tue Apr 29 2014 ...High impact severe weather and flash flooding event expected for the Plains and Mississippi Valley... The stage is set for a high impact severe weather and flash flooding event across the Plains and Mississippi Valley as a deepening surface low slowly lifts northeastward from the the lee of the Central Rockies and anomalous Gulf moisture surges northward ahead of the trailing cold front pushing out of the Great Basin and Southwest. Widespread moderate to heavy rains are expected to develop ahead of this system...impacting locations across the Southern to Central Plains and Middle Mississippi Valley and all the way northward back into the Northern High Plains. Strong to severe storms are likely within convection breaking out ahead of the cold front pushing out through the south central U.S....and flash flooding will certainly be a possibility...especially as the entire system slows down Sunday into Monday. Additional stories with this storm will be the strong and gusty winds surrounding the deep surface cyclone lifting through the Central Plains...and the potential for late season accumulating snows across portions of the northern High Plains as cooler air works its way in behind the system. Unsettled weather is expected for the Northwest as a Pacific front moves inland Saturday evening. A surge of moisture with the boundary...combined with orographic effects...will produce some heavier amounts along the Coastal Ranges and Cascades of the Pacific Northwest...and persistent onshore flow behind the system will keep showers in the forecast through Sunday. Conditions will be slow to clear out across the Northeast where one surface low exiting the coast will be replaced by a second low dropping down from the Lower Great Lakes. Activity should be mostly scattered and light...but a few flakes of snow will be possible over some of the higher elevations of interior New England. Gerhardt Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php