296 FXUS02 KWBC 190609 PMDEPD Extended Forecast Discussion NWS Weather Prediction Center College Park MD 209 AM EDT Sun Apr 19 2026 Valid 12Z Wed Apr 22 2026 - 12Z Sun Apr 26 2026 ...Overview... Unsettled weather will persist through the period as a Pacific mid/upper-level low moves inland over northern California and the Pacific Northwest before ejecting eastward into the Northern Plains. This system will bring strong winds and widespread precipitation, including the potential for moderate to heavy rain and mountain snow. As the trough and surface low interacts with Gulf moisture, the system will strengthen, producing heavy rain and severe weather across central U.S. by late week. Expect a temperature swing with rapid cooling as the frontal passage moves eastward bringing below normal temperatures across much of the West into Northern/Central Plains and Midwest by the weekend. ...Guidance/Predictability Assessment... Models continue to show relatively good agreement on the large scale features of a ridge over central U.S. moving eastward through the period, while the upper low/trough continues to move into central U.S. Model uncertainty focuses mostly on the smaller scale features of the low/trough over the West and the progression and evolution of the system as it moves eastward. The GFS and CMC seems to show agreement on some of the shortwave features compared to the ECMWF. Later in the period, the GFS continues to show another shortwave trough developing while CMC and ECMWF starts to align. Although the deterministic models seemed to show differences that can affect surface low and sensible weather, the ensemble means seem to smooth out some of the differences. Therefore, a even model blend was initially used within the forecast, but shifted towards more of the ECMWF and CMC, with their respected ensemble means towards the later portion of the period. ...Weather/Hazards Highlights... The Pacific frontal system will continue to push east into central U.S. on Thursday, resulting in increasing precipitation chances across Kansas, Missouri, and Iowa. Moderate rainfall are expected, with locally heavy rainfall possible in eastern Kansas and east/northeastern Missouri. Sufficient instability and susceptible flooding conditions from an increase in soil moisture could lead to isolated flooding concerns. This flood threat is also represented by a Marginal Risk of excessive rainfall for portions of Kansas and Missouri in the Day 5/Thursday ERO. The Pacific system and amplified trough over western U.S. will support unsettled conditions from California into the Great Basin and Central Rockies on Wednesday. Multiple embedded shortwaves rotating the base of the trough will bring periods of widespread lower-elevation rain and mountain snow, with locally heavy precipitation possible along favored terrain. By late week, the trough continues to eject eastward, sending a more organized surface system into the Plains by Thursday. This strengthening surface low and frontal boundary is likely to lead to increasing chances for organized convection and severe weather across the Plains into the Mississippi Valley. Moisture return from the Gulf will support the potential for locally heavy rainfall, especially where frontal boundaries slow or become quasi- stationary. Although there may be uncertainty on details surrounding the system, there is a signal for enhanced precipitation that could lead to localized flood risk. In addition, strong gusty winds are expected to build as the system moves across the Intermountain West into the Plains and Mississippi Valley through the week. Accumulating mountain snow will be possible across portions of the central and northern Rockies and into the northern Plains. While impacts should be mainly confined to higher elevations, some travel impacts may be possible. Lower elevation rain may be moderate to heavy at times, particularly along favored upslope regions. By midweek, some isolated showers and storms may be possible for South Florida and southeast Texas near a stalled frontal boundary. In addition, the relatively weak cold front will continue to push through the Ohio Valley, Mid- Atlantic, Northeast Wednesday into Thursday, bringing chances for isolated to scattered showers. Otherwise, much of the Desert Southwest and Southeast will be mainly dry next week, before the cold front drops into the Southern Plains/Mississippi Valley by Friday. As the front pushes eastward, showers and thunderstorms may develop Friday into the weekend. Below normal temperatures over western U.S. will continue through the period with temperatures dropping 10-15 degrees below average across California on Wednesday behind the cold front. Ahead of the system, temperatures 20-30 degrees above average will persist over central U.S. on Wednesday. As the cold front pushes into the Plains by Friday, above normal temperatures gradually move eastward by the end of the week, while below normal temperatures will spread into Northern/Central Plains and Midwest by the weekend. Over into the West, temperatures will begin to moderate late in the period. Oudit 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 $$