844 FXUS02 KWBC 050759 PMDEPD Extended Forecast Discussion NWS Weather Prediction Center College Park MD 359 AM EDT Sun Apr 5 2026 Valid 12Z Wed Apr 08 2026 - 12Z Sun Apr 12 2026 ...Guidance/Predictability Assessment... Model and ensemble medium-range solutions have become better clustered over the past several forecast cycles, bolstering confidence. A composite of the GFS/ECMWF/Canadian offers a solid forecast basis mid-late week that is well supported by ensembles. Predictability broadly remains better than normal later period over much of the nation, but forecast spread does increase in particular with the timing and emphasis of potentially ample system energy to work from the Gulf of Alaska to the Northwest U.S. into next weekend. GFS timing seems best in line with ensemble means and a GEFS/ECMWF/Canadian ensemble mean blend provides a solution well in line with the National Blend of Models and WPC continuity. ...Weather/Hazards Highlights... Flow over the nation this week will remain highlighted by two main streams. An energetic northern stream upper trough/low and deepened surface system will progress from the north-central U.S. midweek to the Northeast/Canadian Maritimes by Friday, slicing through lead/cooled high pressure. A swath of moderate rains and northern periphery snows will accompany windy passage. Another main system well upstream offers timing/emphasis uncertainty with weekend digging and modest rain/mountain snow track into the Northwest. Meanwhile in the southern stream, a lead/wavy frontal boundary lingering over the Gulf and through Florida should prolong a wet/windy pattern this week with wet easterly lower level flow focusing activity over Florida. The WPC Excessive Rainfall Outlook maintains a Day 4/Wednesday Marginal Risk area for eastern coastal Florida.Showers may also affect to a lesser extent Southeast U.S. and Gulf Coastal areas. High pressure will remain in place farther north over the South/Southeast and graduallly heat-up through later period ridge building aloft out from the south-central U.S.. Well upstream, an unsettling/cooling eastern Pacific closed upper trough and surface system will work slowly inland to the West/Southwest with growing light to moderate shower chances Friday into the weekend. Ample lead return flow development then over the central U.S. may portend an emerging heavy rainfall weekend into early next week pattern that has some signal evident beyond that into week 2 as per the Climate Prediction Center (CPC) that may offer broad moderate and high risk potential to monitor. 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 (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 $$