Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 702 PM EDT Sat Sep 23 2023 Valid 12Z Wed Sep 27 2023 - 12Z Sun Oct 01 2023 ...Guidance Evaluation/Preferences... 12 UTC GFS/ECMWF/UKMET/Canadian model guidance seems reasonably clustered into just Wednesday. Rapidly building forecast spread and run-run continuity issues then quickly became unmanageable for most systems, lending preference for a composite of less compatible than normal 12 UTC GEFS/NAEFS/ECMWF ensemble means. This solution has the net effect to maintain as much WPC product continuity as feasible in a pattern with below normal predictability, albeit at the expense of possibly understimating one or more offshore lows that only have minimal guidance signal currently. Given uncertainties, there does seem to be a better than expected signal for development of a threatening Northern Pacific low set to approach the Aleutians and then into the southwest mainland/AKpen by next weekend. Accordingly, prefer to manually deepen this low in the WPC progs given potential support and to offset weakening due to the inherent blending process. ...Weather/Hazards Highlights... Little to no rain/snow is expected over the majority of the interior/mainland well into next week. Given the aforementioned forecast signal for a defined system to approach the Aleutians then downstream in some fashion late next week, some heavier rain is possible there. This would spread into southwestern Alaska then downstream across mainly southern to southeast coastal areas during next weekend. Temperatures are forecast to be within several degrees of typical values for late September, with highs generally in the 40s/50s and lows in the 20s/30s, but cooler along the North Slope where temperatures have a higher probability of being above normal. Schichtel 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