Extended Forecast Discussion NWS Weather Prediction Center College Park MD 325 PM EDT Wed Jul 24 2019 Valid 12Z Sat Jul 27 2019 - 12Z Wed Jul 31 2019 ...Weather Highlights/Threats and Guidance/Predictability Assessment... A persistent feature in the upcoming pattern will be a closed high over the Southwest. Expect daily scattered monsoonal convection will work around the ridge over the southern Great Basin/Rockies/High Plains in upper diffluent flow, and pockets of high heat into interior California and the southern and central Great Basin into the Southwest. Mid-level impulses and wavy surface fronts will cross the northern tier states from the Pacific Northwest eastward to the Great Lakes and northeast. These will enhance moisture, instability and showers/storms/MCS activity with a main focus from the n-central U.S. into the Midwest/Great Lakes. Underneath, guidance suggests eastern US upper troughing will gradually deamplify into the weekend, but linger well into next week as a mid level ridge tends to builds into Florida. A weakening surface front in Florida to the Gulf of Mexico will be a focus for heavier convection and rainfall. NHC is monitoring the northern Gulf of Mexico. Regardless, return warm/moist advection should allow some activity to move north across the lower to mid MS Valley and TN Valley and into the Appalachians next week, lifting inland under increasing influence of southward sagging but uncertain northern stream systems. The WPC medium range product suite was primarily derived from a composite blend of the well clustered guidance from the 06 UTC GFS/GEFS mean and 00 UTC ECMWF/ECMWF ensemble mean. This maintains good WPC continuity. Schichtel Hazards: - Heavy rain across portions of the Central Plains, the Middle Mississippi Valley, the Great Lakes, the Ohio Valley, and the Upper Mississippi Valley, Sun-Mon, Jul 28-Jul 29. - Flooding occurring or imminent across portions of the Central Plains, the Lower Mississippi Valley, the Northern Plains, the Middle Mississippi Valley, the Upper Mississippi Valley, and the Great Lakes. - Excessive heat across portions of California and the Southwest, Sat-Sun, Jul 27-Jul 28. Additional 3-7 Day Hazards information can be found on the WPC medium range hazards chart at: https://www.wpc.ncep.noaa.gov/threats/threats.php WPC medium range 500mb heights, surface systems, weather grids, quantitative precipitation, winter weather outlook probabilities and heat indices are at: https://www.wpc.ncep.noaa.gov/medr/5dayfcst500_wbg.gif https://www.wpc.ncep.noaa.gov/medr/5dayfcst_wbg_conus.gif https://www.wpc.ncep.noaa.gov/5km_grids/5km_gridsbody.html https://www.wpc.ncep.noaa.gov/qpf/day4-7.shtml https://www.wpc.ncep.noaa.gov/wwd/pwpf_d47/pwpf_medr.php?day=4 https://www.wpc.ncep.noaa.gov/heat_index.shtml