Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 402 PM EDT Thu Jul 16 2020 Valid 00Z Fri Jul 17 2020 - 00Z Sun Jul 19 2020 ...There is a slight risk of severe thunderstorms and slight risk of excessive rainfall over parts of the Lower Great Lakes and parts of the Eastern Ohio Valley... ...There is a slight risk of severe thunderstorms over parts of the Upper Mississippi Valley/Upper Great Lakes into the Central Plains... ...There is a slight risk of excessive rainfall over parts of the Middle/Lower Mississippi and parts of the Central/Southern Plains... A front draping across the Lower Great Lakes/Ohio Valley to the Southern Plains northward to the Northern High Plains will be the main focus for severe thunderstorms and areas of heavy rainfall expected to impact by the Lower Great Lakes/Ohio Valley Thursday evening into Friday morning. Meanwhile, a trough of low pressure moving across the Northern Plains into the Upper Midwest. The boundary will trigger showers and thunderstorms over the region through to Friday morning. Heavy rain associated with the thunderstorms will mainly localized scattered flash flooding over parts of the area through Friday morning. As the next upper trough from the Pacific Northwest approaches, the Northern Plains will be under an increasing threat of severe thunderstorms on Friday ahead of a warm front and a developing low pressure system. The excessive heat across the South has moderated to more tolerable levels but heat advisories are still in effect today across the interior sections of the lower Mississippi Valley. Finally, some monsoonal showers and thunderstorms are expected to linger over the central and southern Rockies into the weekend. Ziegenfelder Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php