Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 330 PM EDT Tue Oct 29 2019 Valid 12Z Sat Nov 02 2019 - 12Z Wed Nov 06 2019 Upper level ridging is forecast to remain just south of the Gulf of Alaska through much of the medium range period, only beginning to slide southeastward as deep troughing enters the western Bering/Aleutians by day 7-8 (Tue-Wed). A cold front gets pushed into the Panhandle region this weekend as upper level troughing slides southward across the eastern mainland while a warm, eventually becoming stationary, front lingers in the Gulf atop the upper ridge. Meanwhile, upper ridging across the Bering/eastern Russia slides eastward towards the western Mainland by early next week as a deep upper/surface low ends up somewhere near the western Aleutians. Early period model agreement lends to a majority deterministic blend days 4-5 between the ECMWF/GFS, with small contributions from the ensembles (ECENS/NAEFS/GEFS) to smooth out the smaller scale differences. There remains question to timing/strength of the upper trough as it slides through the mainland with the GFS faster/weaker than a more amplified/slower ECMWF (likely a result of stronger ridging upstream). The ensemble means seemed to provide a good middle ground for this feature. Across the Bering/Aleutians, models may be trending farther south with a developing surface low than previous runs, with most models somewhere near or south of the Aleutians by day 8. Timing differences remain as well as details in the larger scale trough as a whole across the western Bering so a mainly ensemble mean blend seemed to be the best course of action for today at this longer lead time. Sensible weather wise, rain/elevation snows will continue across the Panhandle/southeastern areas with west-southwest flow aloft around the stationary frontal boundary in the Gulf with locally heavy precipitation possible especially early in the period. The next Bering Sea/Aleutians system should bring another round of rain to portions of the western Aleutians by early next week. Temperatures across the eastern Mainland should trend cooler/below normal underneath upper level troughing, with moderation back to near or even a bit above normal by next week especially across the North Slope region as as upper ridging builds north of the state. Santorelli Additional 3-7 Day Hazard information can be found on the WPC medium range hazards chart at: https://www.wpc.ncep.noaa.gov/threats/threats.php - Heavy precipitation across portions of the Alaska Panhandle, Fri, Nov 1. WPC medium range Alaskan products including 500mb, surface fronts/pressures progs and sensible weather grids can also be found at: https://www.wpc.ncep.noaa.gov/alaska/ak_5dayfcst500_wbg.gif https://www.wpc.ncep.noaa.gov/alaska/akmedr.shtml https://www.wpc.ncep.noaa.gov/alaska/ak_5km_gridsbody.html