Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 551 PM EDT Fri Nov 03 2023 Valid 12Z Tue Nov 07 2023 - 12Z Sat Nov 11 2023 ...Multi-day Heavy Precipitation Threat from Southern to Southeast Alaska later next week... ...Guidance Evaluation and Preferences... It remains the case that the latest model and ensemble solutions offer lower than normal forecast spread through medium range time scales, bolstering forecast confidence. A preferred composite of best clustered guidance from the 12 UTC GFS/ECMWF/Canadian models and the 12 UTC GEFS/NAEFS/ECMWF ensemble means seems to offer a good forecast basis for a mid-larger scale system and pattern evolution with seemingly above average predictability and continuity. Manual adjustments applied to the composite will re-deepen best organized systems as consistent with individual predictability as an offset to the inherent weakening as per the blending process. WPC product continuity is well maintained in this manner. ...Overview and Weather/Hazards Highlights... A series of dynamic/amplified upper troughs and deepened surface lows/frontal systems are expected to work from the southern Bering Sea and northern Pacific into the Gulf of Alaska next week. This will spread generally modest activity into the Aleutians and Southwest Alaska early next week and again there by later next week with system progressions. Additionally, enhanced winds and deeper lead/rotating moisture feed looks to increasingly fuel development of a heavier precipitation pattern from Southcentral to Southeast Alaska, especially from later next week into next weekend with deep northern Gulf of Alaska storm low formation. This will include threats for heavy coastal rains and inland/mountain snow, with precipitation totals and impacts accumulating over time. Meanwhile, lingering lowered heights and periodic pockets of modest moisture rotating over an unsettled Interior and North Slope may support scattered light snows next week with protracted easterly fetch winds offering blowing snow situations to monitor locally. Schichtel Hazards: - Heavy precipitation across portions of the Alaska Panhandle and southern Alaska, Tue-Thu, Nov 8-Nov 10. 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 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