Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 439 PM EDT Mon Apr 21 2014 Valid 00Z Tue Apr 22 2014 - 00Z Thu Apr 24 2014 ...Numerous showers and thunderstorms are expected with a cold front crossing the Mississippi River Valley Monday night... ...Late season snowfall accumulations will be possible along the Cascades...Sierra Nevada...and Northern Rockies... Numerous showers and thunderstorms will continue to breakout ahead of a cold front pushing east through the Mississippi River Valley Monday night into Tuesday. The relatively quick progression of the front should minimize the threat for flash flooding; However...there will be a chance for some developing storms to become strong or even severe...especially farther south across southwest Arkansas and southwestward back into Texas. Showers and thunderstorms will continue to accompany the front while it crosses the Appalachians Tuesday evening and clears much of the Atlantic coast Wednesday morning. Widespread above normal temperatures ahead of the front should give way to cooler and drier conditions in the system's wake. Weather in the western U.S. will become increasingly active as a Pacific front slowly makes its way onshore. An expansive area of shower activity is expected across the northwestern corner of the Nation on Tuesday...and orographics will help enhance precipitation over the favored slopes of the terrain. Also...plummeting temperatures behind the front will lower snow elevations and allow for some late season accumulations along the Cascades...Sierra Nevada...and Northern Rockies. By Wednesday evening...the northern portion of the front will push out into the Plains...and rain with embedded thunderstorms should begin developing across the Dakotas. Meanwhile...even as the front progresses east of the Rockies...persistent onshore flow behind the system will keep conditions wet across the Northwest through the middle of the week. Gerhardt Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php