FXUS02 KWBC 081842 PMDEPD Extended Forecast Discussion NWS Weather Prediction Center College Park MD 242 PM EDT Wed Apr 8 2026 Valid 12Z Sat Apr 11 2026 - 12Z Wed Apr 15 2026 ...Overview... The upper level pattern is expected to become amplified this weekend into next week as a potent/cooling upper low/trough digs into the West and warming ridging develops over the East. Upper troughing will work over the western and central U.S., driving a strong surface frontal system across these regions with widespread precipitation chances. Heavy rainfall and severe weather threats are expected in the south-central U.S. this weekend into early next week, and heavy snow will be possible for the Sierra Nevada and portions of the central/southern Rockies. ....Guidance/Predictability Assessment... Model guidance remains in good agreement on the synoptic scale weather pattern through early-to-mid next week, with an expected amount of uncertainty in the smaller scale features. Over the past 24 hours, uncertainty has significantly decreased surrounding energy diving south along the western coast of North America, which was fairly uncertain in previous forecasts. This will bring the next weather system to the Northwest mid-next week. A broad blend of available deterministic models was used as the starting point for WPC's afternoon forecast, with increasing contributions to the blend from ensemble means mid-next week to help smooth out model differences. This maintains good continuity with the National Blend of Models and the previous WPC forecast. ...Weather/Hazards Highlights... A closed Pacific upper trough/low will push a surface system inland over California and the Southwest/Southern Great Basin this weekend as another energetic system dives south along the West Coast. This second system will act to drive a strong frontal system across the western U.S. that will bring widespread precipitation chances, including rain and mountain snow, this weekend into early next week. Conditions will be favorable for heavy snow over the Sierra Nevada with anomalous moisture and strong upslope forcing in place. Heavy snow potential will also spread into portions of the central/southern Rockies early next week as the system progresses. Downstream, moist southerly return flow and instability from the Gulf will prime the atmosphere over the south-central U.S. for heavy rain by this weekend. Marginal Risk threat areas are now in place for the Day 4/Saturday and Day 5/Sunday Excessive Rainfall Outlooks over the southern Plains. The heavy convective rain threat may linger into Monday and expand northeastward into the Mississippi Valley/Midwest as the system strengthens and lifts over the central U.S. and eventually moves toward the Northeast. The strengthening system will also likely support a severe weather threat this weekend into early next week as per SPC. In this pattern, downstream high pressure will emanate from the Southeast to allow a warming trend to spread north toward the Upper Midwest, Great Lakes, and Northeast/Mid-Atlantic this weekend into early next week. Dolan/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 $$