804 FXUS02 KWBC 191927 PMDEPD Extended Forecast Discussion NWS Weather Prediction Center College Park MD 327 PM EDT Fri Jun 19 2026 Valid 12Z Mon Jun 22 2026 - 12Z Fri Jun 26 2026 ...Heavy Rainfall/Flooding Threat from the southern Plains to the Mid-Atlantic early next week... ...Overview... An upper level ridge will linger over the Southwest while mean troughing persists over the Northeast early next week. Several shortwave troughs will track east across the northern tier and push frontal systems and precipitation across the central and eastern U.S., one of which will bring heavy rainfall potential from the southern Plains the Mid-Atlantic on Monday. Late next week, the ridge will weaken as a trough pushes into the West Coast, and a progressive shortwave may allow for increased precipitation chances across the central Plains. ...Guidance/Predictability Assessment... Models remain generally in good agreement, especially early in the period. Given a relatively flat upper level pattern, there are some timing differences as shortwaves track cross the northern tier, but the differences are pretty minor. Model spread increases more significantly by the second half of next week as Pacific energy begins to work its way into the West Coast and cuts through upper level ridging. The past few runs of the GFS have been showing a strong shortwave pushing across the West Thursday into Friday, which seems unlikely given the strength of the ridging extending across the Intermountain West at that time. The ECMWF, EC-AIFS, and CMC show a much weaker wave that is more in line with the model consensus and current forecast thinking. The WPC forecast was initiated with a near even blend of the available deterministic guidance. By mid-week, the GFS was phased out of the blend while ensemble means from the ECENS and GEFS were added in increasing amounts to smooth out model differences. ...Weather/Hazards Highlights... A strong frontal system will push south across the central and eastern U.S. early next week. Anomalous moisture will pool along the frontal boundary from the southern Plains to the Mid-Atlantic and support showers and thunderstorms, some of which may be strong and capable of producing heavy rainfall. Locally heavy rainfall may result in isolated to scattered instances of flash flooding, and the highest flash flood risk is expected to focus from Oklahoma to West Virginia. The front will push south of the Northeast and Mid-Atlantic on Tuesday but will linger across the South and Southeast through mid-week, which will result in continued chances for showers and thunderstorms in these regions. Another frontal system will gradually push across the north-central U.S. and Midwest mid-next week, which will bring precipitation chances from the northern Plains to the Midwest and Great Lakes. This system will be weaker than the first, with more limited precipitation chances. There may be some potential for locally heavy rainfall late next week as the system slows in the Northeast and encounters Atlantic moisture, but there is still quite a bit of uncertainty with this system at that time. An upper level shortwave is expected to cut through the West and emerge in the Great Plains late next week, which looks like it could bring a chance of heavy rainfall to the central Plains Thursday into Friday. This wave should create unstable conditions in a warm, moist air mass that would likely be conducive for thunderstorms with heavy rainfall. The strength of this feature is highly uncertain at this time, which may affect precipitation chances and heavy rainfall potential. Generally near to below normal temperatures appear likely for much of the eastern two-thirds of the country through the the middle of the week, with a slight moderation by the end of the week. The highest heat and humidity will be confined to Texas, near the Gulf Coast, and Florida where HeatRisk values will generally be between moderate and major (with some locally extreme values possible). Meanwhile, above normal temperatures and dry conditions will prevail across the West with highs gradually climbing further into the 100s-110s in the Desert Southwest. Above normal temperatures will spread from the Northwest into the Great Basin/Rockies by midweek. Dolan/Hamrick 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 $$