Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 358 AM EDT Sun Jul 03 2016 Valid 12Z Sun Jul 03 2016 - 12Z Tue Jul 05 2016 ...Flash flooding and severe weather threat over the Middle Mississippi Valley will shift eastward into the Ohio Valley and Central Appalachians... ...Warm and muggy conditions will persist from the southern Plains to the Carolinas... ...Cooling trend expected from the Northwest to the northern Rockies early this week... Shower and thunderstorm activity will continue near a frontal boundary expected to remain stretched from the central Plains to the Mid-Atlantic coast the next few days. The greatest threat for flash flooding and severe weather should be ahead of a wave of low pressure along the front which should track across the Middle Mississippi Valley on Sunday before lifting through the Ohio Valley and towards the central Appalachians on Monday. To the south of the boundary...warm and muggy conditions will persist from the southern Plains to the Carolinas...while an additional few days of dry and pleasant weather are expected well north of the boundary across the Northeast. A pacific cold front will push through the Northwestern states tonight, cross the Northern Rockies on Sunday and track eastward through the northern High Plains on Monday. Showers and a few thunderstorms will develop along and ahead of the advancing system across portions of Montana and the Dakotas. Cooler temperatures are forecast this weekend across much of the Northwest and Intermountain West by the beginning of the week. Gerhardt Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php