Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 405 PM EDT Sun May 24 2015 Valid 00Z Mon May 25 2015 - 00Z Wed May 27 2015 ...Severe thunderstorms and flash flooding possible from portions of the central and southern plains to the Mississippi valley... ...Above average temperatures expected for Memorial Day from the Great Lakes to the Mid-Atlantic and Northeast... Rather stormy conditions will continue for much of the central U.S. over the next couple days as the large-scale weather patten will remain relatively unchanged. A deep upper-level trough over the Intermountain West will move slowly eastward into the plains on Monday. Numerous upper-level disturbances traversing the eastern side of this trough, along with a nearly stationary surface frontal boundary, will keep scattered to widespread showers and thunderstorms in place across much of the central U.S. through Monday. By Tuesday a stronger upper-level disturbance will move into the plains and will begin to shift the focus for showers and thunderstorms eastward toward the Ohio and Tennessee valleys. Flash flooding is possible through Monday across portions of the central/southern plains and Mississippi valley, as heavy rain may fall on already saturated ground. The Storm Prediction Center is also forecasting a slight risk of severe thunderstorms across the same areas. Elsewhere, showers and thunderstorms will also spread eastward across the Great Lakes tonight, with rain possible in the Northeast on Monday as a warm front lifts northward across the regions. Across the West, scattered afternoon and evening showers and thunderstorms will remain common under the influence of the upper-level trough. High pressure at the upper-levels will expand along the Eastern Seaboard, with temperatures rising in earnest. Afternoon high temperatures on Memorial Day are forecast to be 5 to 15 degrees above average Fromm the Great Lakes eastward to the Northeast and the Mid-Atlantic. Ryan Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php