553 FXUS02 KWBC 140718 PMDEPD Extended Forecast Discussion NWS Weather Prediction Center College Park MD 318 AM EDT Wed Oct 14 2026 Valid 12Z Sat Oct 17 2026 - 12Z Wed Oct 21 2026 ...Broad frost/freeze threats across the north-central into the East this weekend and into early next week... ...Overview... A deep trough will move through the East on Saturday with a strong cold front and chilly surface high pressure behind it to bring frost and freeze concerns to a broad area advancing from the Plains into the Midwest and the East this weekend and early next week. Gusty winds associated with this system are possible behind the deep low into Saturday for the Northeast. Meanwhile, an upper low will meander over the Southwest this weekend before weakening. The next trough moves into the West by Monday bringing periods of rain and high elevation snow across much of the West through midweek. ...Guidance/Predictability Assessment... The latest model guidance continues to show good agreement with the large scale pattern through much of the medium range period, with only lingering minor uncertainties in the timing and details of individual systems. An amplified trough will push a strong surface low through the Northeast by Saturday, with a cold front and strong surface high pressure following in its wake. Minor timing and amplitude differences remain with this feature. Meanwhile, models continue to advertise a large and deepening trough moving into the West early to mid next week. Considerable uncertainty remains with this system regarding separation and placement of an upper low over or near the Southwest next Wednesday with plenty of run to run variability in the latest guidance. The updated WPC forecast used a blend of the deterministic guidance through Day 5, increasing the weighting of ensemble mean inclusion to 50 percent of the blend for Days 6 and 7 amidst greater uncertainty out West. Despite the growing uncertainty and likelihood for additional changes in the West, this generally maintains good continuity with the previous WPC forecast for now and was consistent with the 01z National Blend of Models. ...Weather/Hazards Highlights... The deep surface low associated with the East Coast trough will be off into the Canadian Maritimes by Saturday, but may continue to bring gusty winds, especially for higher elevations, as well as some light lake enhanced rain and snow downwind of the lower Great Lakes and upslope in the central and northern Appalachians. As the cold front swings through Florida, showers and storms are possible, with locally heavy to excessive rainfall possible. Much of the West should also see increasing precipitation chances late weekend into next week as another deepening trough moves inland. Fairly widespread precipitation consisting of low elevation rain and high elevation snow are becoming increasingly likely. With that being said, an overall drier pattern is in store by the weekend into early next week for much of the remainder of the country with high pressure taking control. Canadian high pressure is forecast to gradually track across the country behind the cold front into the weekend, cooling temperatures for the central and eastern U.S. and providing fairly broad frost/freeze threats. Meanwhile, above normal temperatures in the West will spread into the north-central U.S. over the weekend and the Central U.S. next week. Deep troughing will bring much below normal temps for much of the West early to mid next week. Santorelli 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 forecast, excessive rainfall outlook, winter weather outlook probabilities, heat indices and Key Messages 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 https://www.wpc.ncep.noaa.gov/#page=ovw $$