Extended Forecast Discussion NWS Weather Prediction Center College Park MD 108 AM EDT Sat Nov 02 2019 Valid 12Z Tue Nov 05 2019 - 12Z Sat Nov 09 2019 ...Pattern Overview and Guidance/Predictability Assessment... Overall, the large scale pattern across the CONUS shows slightly above average predictability during the medium range. A building ridge from the northeastern Pacific north across Alaska toward the Arctic will favor a persistent and broad upper trough across the north central/northeastern U.S. The WPC medium range product suite was primarily derived from a composite blend of the quite compatable latest GEFS/ECMWF ensemble means in lue of reliance on deterministic models that show more run to run continuity issues with the timings/amplitudes of embedded weather systems. ...Weather Highlights/Threats... Broad cyclonic flow aloft will dominate much of the lower 48 next week as a series of impulses reinforce a central North American mean upper longwave trough. This trough may gradually shift eastward as east Pacific upper ridging gradually works inland across the West Coast. Expect mainly dry conditions for much of the West except into later next week as Pacific moisture feeds into/through Pacific Northwest terrain. The downstream pattern will favor the spread and periodic reinforcement with colder than normal airmasses from the Rockies and Central U.S. to the East as post-frontal high pressure cells spill down from Canada. Moisture will be mainly limited across the mid-higher latitudes, but the passage of several clipper lows should support modest snows/light rain swaths over the U.S. northern tier from the Rockies through the Great Lakes/Northeast where activity will be prolonged by lake effect. Moisture may sufficiently feed into/over a wavy lead front to fuel some rains for FL and the coastal Southeast/Carolinas early next week. Moderate activity may develop and focus mid-later next week back from the s-central Plains to the mid-lower MS Valley. Cooled temperatures offer some risk of a light icy coating on the far northern periphery of the return flow. 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