FXUS02 KWBC 090653 PMDEPD Extended Forecast Discussion NWS Weather Prediction Center College Park MD 253 AM EDT Thu Jul 9 2026 Valid 12Z Sun Jul 12 2026 - 12Z Thu Jul 16 2026 ...Major heatwave impacts the North-Central U.S. this weekend into early next week... ...Overview... A broad upper-level ridge expands and strengthens over the central U.S. next week, leading to a significant and dangerous heat wave across the Northern Plains this weekend into next week. A mid- level disturbances will stall out over the Southeast, generating scattered storms and locally heavy rainfall for the region through midweek. Mid-level vortices propagating north out of Mexico will carry waves of monsoonal moisture and storms to the Southwest/Four Corners next week. ...Guidance/Predictability Assessment... Models are in reasonably good agreement on a fairly simple summer pattern across the lower 48 during the medium range. There's minimal disagreement on the strength of mid-level disturbances propagating through the Southeast. Otherwise a general model blend consisting of the available deterministic and Ai guidance was used through day 4 before gradually incorporating the ensemble means starting on day 5. ...Weather/Hazards Highlights... An expanding and deepening Central U.S. ridge will generate dangerous heat across the North-Central U.S. beginning this weekend and continuing through early next week. Daily maximum and minimum temperatures will be between 15-25 degrees above average, with night time lows struggling to drop below 70 degrees in many places. Heat indices between 100-110 degrees will be exacerbated by the little overnight relief, which combined together support major heat risk for much of the Northern Plains. A synoptic front pushing south through the Tennessee Valley and Southeast will eventually stall out over the Gulf Coast and act as a focus for showers and thunderstorms beginning late this weekend. Some storms may generate pockets of heavy rainfall that could lead to isolated instances of flash flooding. A subtropical ridge will develop over the Southeast and Florida Peninsula heading into the latter part of next week and renew heat risk concerns for the region. Increasing southerly flow around the western periphery of the Central U.S. ridge will draw monsoonal moisture into the southern Four Corners and Great Basin later this weekend and into early next week. This moisture will likely lead to the development of scattered to numerous showers and thunderstorms with the potential to produce heavy rainfall and localized flash flooding. Kebede Additional 3-7 Day Hazard information can be found on the WPC medium range hazards outlook chart at: https://www.wpc.ncep.noaa.gov/threats/threats.php WPC medium range 500mb heights, surface systems, weather grids, quantitative precipitation forecast, excessive rainfall outlook, winter weather outlook probabilities, heat indices and Key Messages 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/#page=ero https://www.wpc.ncep.noaa.gov/wwd/pwpf_d47/pwpf_medr.php?day=4 https://www.wpc.ncep.noaa.gov/heat_index.shtml https://www.wpc.ncep.noaa.gov/#page=ovw $$