Alaska Extended Forecast Discussion National Weather Service College Park MD 631 PM EDT Sun Aug 3 2025 Valid 12Z Thu 07 Aug 2025 - 12Z Mon 11 Aug 2025 ...Synoptic Overview... An upper level low over the AkPen at the start of the period will move northeast and weaken into the weekend, effectively dissipating by Monday. The upper level low and subsequent trough will support North Pacific lows as they round the jet stream and then move into the Gulf, eventually impacting the Panhandle. The primary of these waves this weekend could cause heavy rain over much of the Panhandle. Meanwhile an upper level trough over the Arctic on Thursday will move south and cut off a low, likely north of the Chukotsk Peninsula, where it will subsequently stall out, barely moving through Monday. The low is likely to gradually weaken Sunday and Monday. The surface low over the AKPen Thursday will rapidly weaken this weekend as it stalls southwest of Kodiak Island. An additional North Pacific low will move into the Panhandle as it absorbs the weakened Kodiak low as it tracks northeast across the Gulf. ...Guidance Evaluation and Preferences... The 06Z CMC and the 12Z GFS were the best agreed models in the suite. The 12Z EC became more of an outlier than its predecessor regarding the Arctic low and where it sets up, depicting the center of the low over Northwest Alaska while the rest of the guidance was west of the Bering Strait. A typical model blend was used, blending the deterministics for Days 4 and 5, then adding more ensembles through the end of the period. The exception, as noted, was that the 12Z EC was an outlier and left out of the model blend. ...Weather/Hazards Highlights... No hazardous weather is expected across Alaska through the period. Warmer than normal temperatures will persist across the eastern Interior, as colder temperatures build across the North Slope and western Alaska in response to the strengthening low/trough over the Bering Strait. Heavy rain is likely to impact the Panhandle this weekend, but a more progressive, zonal flow in the upper levels should allow the low to continue moving into Canada, reducing the time when heavy rain is possible. Nonetheless, the Mendenhall Glacier area continues to be an area of focus for potential future flooding concerns, where heavy rain could contribute to the severity of any flooding. Heavy rain is also possible for a time along the favored upslope areas of the AkPen and Kodiak Island, but due to the rapid weakening of the low, despite its slow movement, heavy rain should only occur over a short duration. && Wegman 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