307 FXUS02 KWBC 160650 PMDEPD Extended Forecast Discussion NWS Weather Prediction Center College Park MD 250 AM EDT Tue Jun 16 2026 Valid 12Z Fri Jun 19 2026 - 12Z Tue Jun 23 2026 ...Significant Excessive Rainfall/Flooding Threat to persist for the Gulf Coast States and Southeast into Friday/Saturday... ...Weekend to early next week heavy rains emerge from the Central Plains/Midwest/Ohio Valley to the Northeast/Mid-Atlantic... ...Pattern Overview and Guidance/Predictability Assessment... An emerging tropical feature set to work from Texas Coast to the Gulf Coast/Southeast through Friday will pool deep return moisture to fuel multi-day excessive rainall/flooding threats. NHC now has early week probability of Texas Coast tropical development at 50%. Elsewhere, hot West/Southwest upper ridging will tend to flatten and become east-west oriented over the southern tier this period as east Pacific upper trough energies progress over the northern two- thirds of our fine nation in increasingly zonal flow with ejection of leading and amplified east-central mean U.S. upper troughing. Guidance forecast spread aside from tropical differences remains better than average for the weekend into Monday when a composite guidance solution seems reasonable. System uncertainies grow to more normal levels next week with flow transition. Accordingly, mostly favor a compatible multi-model ensemble mean and machine learning guidance blend then versus much reliance on any specific solution. This also acts to maintain best WPC product continuity. ...Weather/Hazards Highlights... A wave of tropical origin lifts up the Texas coast over the next couple of days, tracking over the Southeast through Friday as it interacts with an existing frontal boundary. Deep tropical moisture influx and instability will surge in from the coast to fuel a notable excessive rainfall/flash flooding threat. Please also see the WPC Excessive Rainfall Discussion (ERD) and Hazards Outlook Chart (linked below) for additional risk details. This weekend, a Colorado low looks to form and track over the Central Plains to the Great Lakes then the Northeast. Deepening moisture lifting into this system and associated frontal system genesis should lead to sizable areas of heavy convective rain with weekend focus across the Central Plains/Midwest/Ohio Valley states expanding to the Northeast/Mid-Atlantic early next week. West Coast upper ridging keeps temperatures 10-20 degrees above normal over the Northwest/northern Intermountain West through Friday with a northern stream low over BC breaking down the ridge a into the weekend. Some ridging looks to return to the West Coast early next week. Otherwise, closer to normal summer temperatures are expected across the lower 48, though the tropical moisture along the Gulf Coast will maintain high nighttime temperatures that along with southern tier upper ridging may support hazardous heat over portions of the Florida Peninsula and the Gulf Coast. 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 $$