Extended Forecast Discussion NWS Weather Prediction Center College Park MD 258 AM EDT Wed Apr 29 2020 Valid 12Z Sat May 02 2020 - 12Z Wed May 06 2020 ...Much above normal temperatures for the South... ...A series of active weather systems to affect the nation... ...Guidance/Predictability Assessment... The WPC medium range product suite was mainly derived from a blend of the 18 UTC GEFS mean and reasonably compatible 12 UTC ECMWF ensemble mean days 3-7. The latest 00 UTC GFS and recent ECMWF runs seem in better system amplitude/timing agreement with these ensemble means, bolstering forecast confidence. WPC continuity was well maintained. ...Weather/Hazard Highlights... A pesky closed upper low/trough will slowly move over the Northeast Saturday. The amplified and cooling system will support lingering moderate rains and windy conditions across the region as deepened moisture wraps inland around a developing coastal low. The exiting storm will pose a weekend maritime hazard. Upper ridging and hot conditions will spread from the Southwest/Rockies through the South this weekend and linger early next week. Temperatures will range up to 10-20F above normal, with some daily records possible, especially over the southern Plains. Upper trough and jet energies will amplify/dig from the north-central U.S. through the East this weekend. Rainfall may focus from the central Rockies/Plains through the Mid-MS/OH Valleys through the central Appalachians. Dynamics, instability and progressive frontal push may support some organized strong to severe convection with locally heavier downpours, but smaller scale details remain less certain. Upstream, robust eastern Pacific trough energy/height falls will work inland across the West Sun into Mon and spread a swath of moderate precipitation mainly from the Northwest through the northern Rockies. Favored higher elevations may see periods of enhanced snow. The dynamic system should emerge over the north-central U.S. Mon before digging into the East mid next week. Forecast spread and guidance uncertainty quickly increases at these longer time frames, but the larger scale flow suggests that an associated frontal system and lead instability may favor a risk of additional strong to severe convection with some organized heavy convective downpours from the north-central Plains southeastward through the MS Valley through the Appalachians. Schichtel Additional 3-7 Day Hazards information can be found on the WPC medium range hazards chart at: https://www.wpc.ncep.noaa.gov/threats/threats.php WPC medium range 500mb heights, surface systems, weather grids, quantitative precipitation, winter weather outlook probabilities and heat indices 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/wwd/pwpf_d47/pwpf_medr.php?day=4 https://www.wpc.ncep.noaa.gov/heat_index.shtml