Extended Forecast Discussion NWS Weather Prediction Center College Park MD 300 AM EDT Wed Mar 27 2019 Valid 12Z Sat Mar 30 2019 - 12Z Wed Apr 03 2019 ...Overview and Weather Highlights and Hazards... Upper ridging over western Canada will refocus into Alaska to favor troughing through central/eastern Canada and the Upper Midwest/Great Lakes/Northeast. Lead low pressure will exit through the eastern Great Lakes/St. Lawrence Valley this weekend as the trailing cold front traverses the s-central and eastern U.S., lingering across Florida and the Gulf of Mexico. This system may bring a variety of weather including some weekend snow from the upper Great Lakes to northern New England and moderate rainfall and convection ahead of and along the front. A series of southern stream Pacific shortwaves meanwhile progress underneath into an unsettled West, then eastward over the U.S. southern tier. This may invigorate Gulf of Mexico frontal wave genesis next week. This would lead to increased rains for portions of the Southeast and especially Florida, leading into possible western Atlantic coastal low development. Upstream, a renewed system push into the West Coast early next week may result in periods of moderate rain and heavier elevation snows from the Northwest to the northern Rockies. ...Guidance Assessment/Preferences... The GFS/ECMWF and GEFS/ECMWF ensemble means seem to offer reasonably similar larger scale pattern evolutions, but less than stellar consistency with stream interactions and timing/strength of a multitude of smaller scale systems embedded with the flow. Prefer a composite blend to mitigate this with blend weighting transitioning from in favor of these determinitsic models this weekend to these ensemble means next week. 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