Extended Forecast Discussion NWS Weather Prediction Center College Park MD 257 AM EDT Tue Mar 29 2022 Valid 12Z Fri Apr 01 2022 - 12Z Tue Apr 05 2022 ...Guidance Evaluation/Predictability Assessment... The WPC medium range product suite was primarily derived from a composite of best clustered guidance from the 12 UTC GFS/ECMWF and GEFS/ECMWF ensemble means along with the 01 UTC National Blend of Models days 3-5 (Friday-Sunday). Embedded smaller scale system differences and ample run to run continuity variances remain problematic despite reasonably similar larger scale pattern evolutions. Opted to blend just the generally compatible ensemble means by early next week to mitigate the less predictable forecast components amid steadily growing forecast spread. Overall, WPC product continuity is reasonably maintained with this strategy and the forecast seems in line with a similar composite of newer 00 UTC guidance. ...Overview and Weather Highlights/Threats... A deep cyclone will eject across a stormy eastern Canada Friday as high winds and some wrapping snows persist to the lee of the Great Lakes and across the Northeast on the backside of the cyclone. A trailing front will sweep off the East Coast, but should stall and linger over Florida, the Gulf of Mexico/Gulf Coast and into northern Mexico. Upstream, a series of progressive upper troughs and frontal systems forecast to dig with some uncertainty through the West late week into early next week could each provide an opportunity for periods of modest wintry weather across the north-central Intermountain West/Rockies. System progressions downstream within an emerging southern stream may meanwhile favor modest precipitation from the central Plains and Midwest to the Appalachians/Mid-Atlantic, but deeper return moisture focus into wavy fronts and a stalled lead front offers potential to fuel some heavy downpours from the Gulf Coast to the Southeast into the weekend. By early next week there is also a growing guidance signal to bring more energetic Pacific jet flow toward the West Coast. This may transport deeper moisture to fuel and emerging precipitation pattern focus into the Pacific Northwest to include heavy terrain enhancing snows. 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, experimental excessive rainfall outlook, 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/#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