Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 507 AM EDT Sun Aug 09 2015 Valid 12Z Sun Aug 09 2015 - 12Z Tue Aug 11 2015 ...There is a slight risk of severe thunderstorms over parts of the Central High Plains... ...Heavy rain possible over parts of the Middle Mississippi Valley and the Central Rockies... A slow moving frontal system over the Northern Plains will morph together with a quasi-stationary front extending from the Southeast to the Central Plains by Monday morning. Showers and thunderstorms will develop along this system as it progresses eastward through Tuesday morning. Conditions will be favorable for strong to severe thunderstorms to initiate this afternoon and evening across portions of South Dakota, northeast Nebraska and extreme northwest Iowa. The Storm Prediction Center has issued a slight risk for this region. With the slow movement with this system, and ample moisture availability, heavy rainfall will be possible through Monday morning. Areas with the best potential for higher rainfall rates will be South Dakota and the Middle Mississippi Valley. Monsoonal moisture and daytime heating will aid in the development of showers and thunderstorms over parts of the Southern/Central Rockies through Monday. Confidence of excessive rainfall for southeast Colorado and northeast New Mexico continues to rise. This region could receive 2 to 3 inches of rain. Rapid runoff and flash flooding will be of concern Monday and Tuesday. Periods of light rain is expected over the next couple of days for the Pacific northwest. Campbell Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php