Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 633 PM EDT Tue Jul 20 2021 Valid 12Z Sat Jul 24 2021 - 12Z Wed Jul 28 2021 ...Guidance/Predictability Evaluation... The latest available model guidance was reasonably clustered for the Alaska region such that the days 4-6 forecast was primarily a blend of the 12Z GFS/ECMWF/CMC/UKMET deterministic runs. For the remainder of the medium range period (days 7-8), the relatively persistent upper level troughing over the region is forecast with varying degrees of amplitude and strength. The main areas of question lie with shortwave energy tracking across the Aleutians and also dropping down across the northwest mainland area. The stagnant cut off low in the Gulf of Alaska is forecast to subside late in the forecast period, except for the deterministic GFS, which keeps its feature throughout. Given the clustering of the signal but lower confidence in the details, the ensemble means were a good approach for the 500 pattern and subsequent surface features. The ECENS was favored to maintain some continuity from the last cycle. ...Weather/Threats Highlights... Rain showers are expected for the eastern Kenai Peninsula on Saturday and east into the Panhandle on Saturday and Sunday ahead of a storm system over the Gulf of Alaska. There is reasonable convergence between guidance for marginally hazardous rainfall totals, in the area, but dry antecedent conditions will limit any impact from the rain. Additionally, generally below normal temperatures are expected across the mainland through the period, particularly in the Far North. These temperatures are not expected to be hazardous at this time. Taylor Hazards: No significant hazards are expected over Alaska during this forecast period. 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