109 FXUS02 KWBC 111947 PMDEPD Extended Forecast Discussion NWS Weather Prediction Center College Park MD 347 PM EDT Sat Apr 11 2026 Valid 12Z Tue Apr 14 2026 - 12Z Sat Apr 18 2026 ***Multiple rounds of heavy rain and severe weather across the Plains next week*** ...General Overview... An amplified upper level flow pattern will be in place next week across the Continental U.S., with an upper ridge situated east of the Mississippi River, and a general trough over the West. Multiple impulses will eject eastward across the Plains and provide forcing for episodes of heavy rain and severe thunderstorms from the southern Plains to the Great Lakes. Summer-like temperatures will be commonplace across the eastern half of the country with highs well into the 80s and lower 90s by the middle of the week, while snow will be likely across the central and northern Rockies. ....Guidance/Predictability Assessment... The latest 00/06Z guidance remains in fairly decent agreement on the overall pattern through most of next week with mean upper- ridging over the eastern U.S., mean upper-troughing over the western U.S., and an active southwesterly flow pattern over the central U.S. as these features tend to remain in place. There are some differences in the evolution of individual shortwaves with split-stream frontal systems progressing through the flow mid- week. The GFS has remained a bit of an outlier with a faster/weaker upper-wave rounding north of the upper-ridge compared to the ECMWF/ECMWF AIFS/CMC which are slower and retain a stronger low pressure/frontal system passing through the Midwest. Despite the complexity of the pattern and differences in the guidance the NBM QPF overall looked reasonable in coverage and amounts ahead of a stalling front the Plains to Midwest and then east north of the ridge, except perhaps a bit dry from the Ohio Valley to New England. There remains some uncertainty with the portion of the front through the Northeast and how far south it could get, potentially affecting the duration of anomalous and possible record-tying/breaking heat to the south from the Ohio Valley to the Mid-Atlantic, though the trend has been to hold further north. Thereafter, there are greater differences with the next system upstream from the west and a potential pattern change by next weekend. Both the latest GFS and CMC bring an upper-wave over the northeastern Pacific east along the northern tier to the central U.S., with a strong lee low pressure system developing by Friday. On the other hand, the upper-wave in the ECMWF digs southward over the West, helping to reinforce the mean upper-troughing and delaying system progression eastward into the central U.S. compared to the other guidance. The 12Z runs of the ECMWF and GFS tended to converge a bit on the evolution though the ECMWF remains slower. Despite this, QPF in the NBM looked to be a reasonable compromise solution favoring potential precipitation over the Midwest and central/southern Plains similar to the GEFS/ECens means. The updated WPC forecast initially used a composite blend of the ECMWF/ECMWF AIFS/CMC and 06Z GFS before reducing the contribution of the GFS as the system evolution over the central/eastern U.S. diverged from the other guidance. Then, for the mid- to latter part of the forecast, the ECMWF is reduced and eventually removed while retaining the ECMWF AIFS/CMC/GFS given its noted outlier solution over the West. A contribution from the ECens/GEFS means is steadily increased to 45% of the blend by the end of the period as the deterministic guidance begins to diverge, particularly with the progression of the next system over the central U.S. ...Weather/Hazards Highlights... A very active weather pattern develops across the Central U.S. through the middle to end of the week, with multiple rounds of strong to severe thunderstorms expected from Texas to the Midwest states, given favorable wind shear and instability in place. The moisture will be channeled northward from the western Gulf to the Midwest between the eastern U.S. upper ridge and the trough over the Rockies, and the limited eastward progression each day will likely result in areas that have excessive rainfall leading to some instances of flash flooding. Marginal Risk areas will be valid across portions of the Midwest to the western Great Lakes Tuesday into Wednesday where a few mesoscale convective systems are likely to develop. Additional heavy rainfall is likely beyond this time across portions of the central/southern Plains and the Midwest. Out West, an amplifying shortwave and associated cold front will bring a renewed round of coastal rain and mountain snow to the Pacific Northwest Tuesday into Wednesday, with potentially 1-2+ feet of snow for the Cascades. This moisture then moves inland across the northern Rockies through the middle of the week, with moderate to locally heavy snow from northern Idaho to northwestern Wyoming. Lighter snows will be possible across the higher terrain of Utah and Colorado. Periodic gustier winds can also be expected through the northern/central Rockies and into the adjacent High Plains through the period with multiple system passages. Temperatures will also be making weather headlines next week across much of the Eastern U.S., with highs reaching into the mid to upper 80s for many areas, and even some lower 90s across the Southeast and Mid-Atlantic region going into the middle of the week as the early season heatwave reaches it peak. Numerous daily record highs will be possible, especially Wednesday and Thursday. Although these temperatures and humidity will generally remain lower than more concerning conditions over the Summer, a couple days of highs in the low to mid-90s and overnight lows that might remain near 70 could lead to a locally higher risk of heat stress across portions of central/southern Virginia by Thursday, particularly given the early nature of the heat compared to average. There should be a modest cooling trend towards the end of the week as the frontal boundary drops southward from the Ohio Valley to the Mid- Atlantic, and remaining hot across the Deep South and the Carolinas. Out West, readings should generally be near to below average with the upper trough in place and increased cloud cover and precipitation. Putnam/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 (QPF), excessive rainfall outlook (ERO), winter weather outlook (WWO) probabilities, heat indices, and Key Messages can be accessed from: 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 $$