Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 715 PM EDT Sun Aug 13 2023 Valid 12Z Thu Aug 17 2023 - 12Z Mon Aug 21 2023 ...General Overview... The overall weather pattern across the Alaska domain should be relatively uneventful for the most part going into the extended forecast period. The rainfall event across the southeastern coastal areas should be tapering off going into Thursday as the Gulf low steadily weakens. A polar vortex will gradually settle south towards the Arctic Coast by next weekend, but the coldest temperature anomalies with this should remain north of the state. Looking ahead to next Monday, the extratropical remnants of Typhoon Lan may approach central and western portions of the Aleutians. ...Guidance Evaluation/Preferences... The 12Z model guidance suite is in generally good agreement for the middle of next week, but that changes going into Friday with multiple timing and amplitude differences across the Gulf region. The GFS is stronger with a low entering the northern Gulf compared to the other guidance by late Friday and into Saturday. The low tracks with the 12Z ECMWF are closest to previous WPC continuity from yesterday. Taking these factors into account, the fronts/pressures forecast is primarily derived from about a third previous WPC continuity, third 12Z ECMWF, and about 10% each of the GFS, CMC, and ECENS through Saturday, and then increasing use of the ensemble means to about 50% by next Monday. ...Weather/Hazards Highlights... Improving weather conditions can be expected for the southern coast and the southeast Panhandle region to close out the work week with showers becoming more isolated to scattered in coverage as the onshore moisture plume weakens. However, rainfall is forecast to increase in coverage across north-central portions of the mainland as a slow moving cold front drops south from the Arctic, with the potential for scattered 1-2 inch rainfall totals over the Thursday through Saturday time period. Temperatures are expected to generally be near to slightly above average across much of the Interior region through the end of the week, and slightly cooler than average across southern portions of the state on Thursday where clouds and rain will be more prevalent. Depending on how far south the polar vortex gets, below average temperatures are also expected to settle in across portions of the northwestern mainland by Friday and into next weekend. Hamrick 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