Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 400 AM EDT Wed Aug 09 2017 Valid 12Z Wed Aug 09 2017 - 12Z Fri Aug 11 2017 ...Showers and thunderstorms expected throughout the Southeast and southern Plains... ...Precipitation to develop along the front from the Great Lakes to the northern Plains... ...Thunderstorms expected to develop in the central Plains and move into the Middle Mississippi Valley... Scattered to widespread showers and thunderstorms are forecast along a front that will lift through Gulf Coast and Southeast states through Friday. Some of these storms could produce heavy downpours which may lead to flash flooding. Refer to WPC's excessive rainfall forecasts for additional information. Across the northern-tier of the U.S. another cold frontal system will pass through the Dakotas, Upper Midwest and the Great Lakes region. The cold front will sag southward into the Central Plains while the portion over the Great lakes will stall. Showers and thunderstorms are expected to initiate along and east of this system and will persist through Friday morning. Heavy rainfall will likely focus just east of the Southern/Central Rockies extending to eastern Kansas and Oklahoma as an upper level disturbance moves out of the Rockies and crosses over the Plains by this afternoon. Areal averages of 1 to 2 inches are forecast, although isolated higher amounts may occur. Flash flooding will be a potential threat along with a slight risk for severe thunderstorms. Isolated showers and thunderstorms will increase across the Great Basin and portions of California as an upper-level low stalls over the region. Campbell Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php