223 FXUS02 KWBC 220744 PMDEPD Extended Forecast Discussion NWS Weather Prediction Center College Park MD 344 AM EDT Wed Jul 22 2026 Valid 12Z Sat Jul 25 2026 - 12Z Wed Jul 29 2026 ...Southeast U.S. Heavy Rainfall/Flooding threat into Saturday... ...West-Central to Southern U.S. Hazardous Heat this weekend into next week as monsoonal rains focus over the Four Corners states... ...Pattern overview and Guidance/Predictability Assessment... Latest guidance shows good agreement and forecast confidence with larger scale upper pattern development and persistence this weekend into next week. The amplified and blocky pattern will feature a warming Intermountain West/Southwest/Rockies/Plains/South ridge sandwiched between unsettling troughs just off the West Coast and over the East. There remain uncertainties with individual systems working through the flow and local sensible weather impacts, but differences seem reasonably mitigated by a favored broad guidance blend as consistent with individual predictability. WPC product and threat messaging continuity is well maintained. ...Weather/Hazards Highlights... Broad upper ridge influence offers Major to Extreme HeatRisk threat areas broadly this weekend into next week from the Southwest/Intermountain West/Rockies through the Northern Plains down through the south-central U.S. and the South. Expect spotty record highs and more widespread record overnight lows to limit relief from the heatwave. Some moderating flow with and around the weatern periphery of the upper ridge will occur as significant monsoonal moisture feeds into the Southwest and Intermountain West/Rockies this week, with the next influx of moisture from Mexico possible early next week. Scattered to numerous showers and thunderstorms are expected with heavy rainfall and localized flash flooding potentials. Sensitive places such as burn scars, steep terrain, etc. would be the most vulnerable to possible flooding concerns. WPC Excessive Rainfall Outlook (ERO) Marginal Risks are now in place through the weekend. Elsewhere, convection with enhanced heavy rains are forecast to linger over the Southeast through Saturday given support aloft and slow/wavy frontal progression, with additional activity back through the Southern Appalachians/Tennessee Valley as covered by an ERO Marginal Risk area. Ample subsequent northern stream system energies set to dig into the upper trough position over the East should suppprt organized enhanced to heavy convective rainfall potential from the Great Lakes/Ohio Valley this weekend through the Eastern Seaboard through early-mid next week. Persistent upper troughing and embedded moisture feed offers mid- summer weekend light rain chances to clip the Pacific Northwest. Schichtel 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 $$