Extended Forecast Discussion NWS Weather Prediction Center College Park MD 158 AM EST Fri Nov 08 2019 Valid 12Z Mon Nov 11 2019 - 12Z Fri Nov 15 2019 ...Record cold next week with an inland Northeast heavy snow threat... ...Pattern Overview and Guidance/Predictability Assessment... Upper ridging over western Canada and also near the Azores will favor broad troughing over the eastern 2/3rds of the CONUS next week. Concurrently, a lost upper low near Baja California will slowly push across northern Mexico to eventually rejoin the southern edge of the westerlies late next week. The models/ensembles were in good agreement on the larger/synoptic scale but differed in timing/track/strength of the embedded systems. Overall the 12Z ECMWF and the 18Z GFS clustered fairly well with their ensemble means and each other to form a starting point for the forecast. System of interest on Tuesday near Long Island/Block Island will lift into Nova Scotia/New Brunswick with modest to perhaps locally heavy snow for interior/northern New England. ...Weather Highlights/Threats... Cold Canadian high pressure will spill out of eastern Montana Monday morning through the Central Plains and into the Ohio Valley by Wednesday, bringing in well below average temperatures that will likely break daily records across a sizable area of the eastern half of the CONUS Mon-Wed. Conversely, some record highs are possible on Monday over northern California under the upper axis. Front in the east will carry low pressure just off New England with a swath of snow to the northwest of the track and lake-effect snows for the Great Lakes with very cold temperatures aloft over still warm water. Temperatures will moderate for later in the week as the high moves offshore and weakens, but highs will remain about 10-15 degrees below average along and east of the Mississippi into next Friday. West of the Rockies, temperatures will stay above average by about 5-10 degrees. Precipitation could expand across the Gulf Coast late next week as the upper low once over western Mexico moves eastward along the I-10 corridor coincident with a weaker front to its north. Fracasso 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