Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 350 PM EDT Sun Sep 22 2019 Valid 00Z Mon Sep 23 2019 - 00Z Wed Sep 25 2019 ...Flood Watch are up for parts of the Upper/Middle Mississippi Valley, Upper Great Lakes, and Middle Missouri Valley... ...Temperatures will be 10 to 20 degrees above average over much of the eastern United States... A strong cold front currently extending from the Upper Great Lakes southwestward to the Middle Mississippi Valley and Southern Plains will move eastward to off the Northeast/Mid-Atlantic Coast by Tuesday evening. This boundary will produce numerous showers and thunderstorms over parts of the Great Lakes into Central/Southern Plains. Heavy rain associated with these storms may produce isolated Flash Flooding in localized places that experience rapid runoff with heavy rain. Total rainfall amounts in these areas could add up to around half an inch to 1,50 inches, with locally higher amounts. On Monday into Tuesday, weaker and more scattered showers and thunderstorms will advance into the Ohio Valley/Lower Great Lakes into the Southern Plains then into the Northeast. The combination of an approaching cold front and moisture associated with what was Tropical Depression Lorena will lead to the possibility of severe storms and flash flooding across portions of Arizona on Monday into Tuesday morning. The Storm Prediction Center has issued a Slight Risk for severe thunderstorms, with frequent lightening, strong winds, and damaging hail being the main threat. A Slight Risk of excessive rainfall has also been issued over roughly the same area, where around an inch of rain could fall by Tuesday morning. Ahead of the cold front, temperatures will remain as much as 10 to 20 degrees above average across much of the eastern U.S. through Tuesday. High temperatures will peak in the 80s and low 90s, with overnight lows only dropping into the 60s. These low temperatures could break several daily high minimum temperature records across the Northeast. Ziegenfelder Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php