Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 416 PM EDT Mon Sep 21 2015 Valid 00Z Tue Sep 22 2015 - 00Z Thu Sep 24 2015 ...Tropical Depression Sixteen-E to bring the possibility of flash flooding to portions of the Southwest... ...Excessive rain possible for portions of the Central/Northern Plains and Upper Mississippi Valley... Portions of the Mexico and the Desert Southwest will be rather wet as Tropical Depression Sixteen-E continues to track inland this afternoon. A vast region, spanning from north of Los Angeles, California to Del Rio, Texas and areas to the south, has precipitable water anomalies of 1 to 4 standard deviations above the seasonal average over the next few days. Most of Arizona, New Mexico and southern California have a threat of excessive rainfall and flash flooding through Tuesday morning as the Sixteen-E passes through. Forecast amount of 1 to 3 inches will be common over this area, with isolated higher amounts possible. The areal extent for excessive rainfall will be less on Tuesday as the tropical system dissipates over areas of higher terrain. Refer to the latest products issued by the National Hurricane Center for the latest information on Sixteen-E. Scattered showers and thunderstorms will persist across the Four Corners region into Wednesday as moisture remains present in the mid-levels. A front will stall across the Central Plains by Tuesday and will drift slowly north as a warm front on Wednesday as most of the CONUS will be in a zonal pattern. Showers and thunderstorms will be possible along this boundary through Tuesday night, with much better coverage and intensity on Wednesday. A swath from northwest Kansas to northern Wisconsin will have the potential for higher rainfall amounts as that segment of the front advances across the northern Plains and Upper Midwest. Campbell Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php