734 FXUS02 KWBC 170654 PMDEPD Extended Forecast Discussion NWS Weather Prediction Center College Park MD 254 AM EDT Wed Jun 17 2026 Valid 12Z Sat Jun 20 2026 - 12Z Wed Jun 24 2026 ...Weekend Heavy Rainfall/Flooding and Severe Weather Threat for the Central Plains/Mid-Mississippi/Lower Ohio Valley/Mid-South... ...Pattern Overview and Guidance/Predictability Assessment... Upper ridging will focus heat over the nation's southern tier as a series of active Pacific systems progress with less certain timing over the northern two-thirds of the lower 48 in quasi-zonal flow. Guidance forecast spread seems better than normal for the weekend, then increases next week with flow transition. Accordingly, favor a multi-model, ensemble mean and machine learning guidance blend for the period which does not favor any specific deterministic solution. This acts to maintain good WPC product continuity. ...Weather/Hazards Highlights... Weekend Central Plains frontal low genesis and Midwest/Northeast track early next week sets the stage for a stormy weather period. Expect some showers/thunderstorms with energies on the northern periphery over the northern Rockies/Plains and Upper Midwest. Meanwhile, deepening moisture/instability and upper dynamic and frontal system support to the south will lead to threats of heavy rain and flooding with focus across the Central Plains, the Mid- Mississippi/Ohio Valleys states and the Mid-South where the WPC Excessive Rainfall Outlook offers weekend Marginal and Slight Risk areas. SPC also depicts a risk for severe weather over the Central Plains Saturday. Lingering organized convective rainfall focus will work into the East and shift down over a moistened South into early-mid next week with frontal progression and shortwave support. 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 $$