Alaska Extended Forecast Discussion National Weather Service College Park MD 645 PM EDT Thu Jul 31 2025 Valid 12Z Mon 04 Aug 2025 - 12Z Fri 08 Aug 2025 ...General Overview... The beginning of next week will feature a closed upper low situated over the Bering Sea, and a weaker closed low lingering over Southeast Alaska with an accompanying surface low. By midweek, shortwave energy pivoting around the Bering Sea low will likely develop a new surface low that should enter the Gulf region towards the end of the week with more unsettled weather for the southern coastal areas. Across the north, a relatively strong cold front will herald the arrival of colder temperatures from the Brooks Range and points north, in contrast to the above average readings expected this weekend, while still remaining pleasantly warm across much of the central Interior. ...Guidance Evaluation/Preferences... There is generally good overall model agreement to begin the forecast period Monday, and this holds true going into Tuesday as well. The 12Z GFS is generally stronger with the triple point low that develops south of the Alaska Peninsula on Tuesday, and it is also stronger with a wave of low pressure along the front near the Arctic Coast for early in the week. The CMC gets considerably stronger with the low moving into the eastern Gulf by Wednesday into Thursday, and has no support from the AIFS guidance by that time. Otherwise, there is good overall agreement through much of the week with the surface pressure pattern over mainland Alaska, and more spread across the North Pacific. Taking these factors into account, the WPC fronts/pressures forecast was primarily derived from a multi-deterministic model blend through Tuesday, and then gradually increased percentages of the ensemble means to about half by next Friday and dropping the CMC by Thursday owing to its differences across the Gulf. ...Weather/Hazards Highlights... Isolated to scattered afternoon and evening showers and thunderstorms can be expected across the Interior most days, with greater concentration ahead of the cold front across the Brooks Range and adjacent portions of the Interior. In addition, moist onshore flow ahead of the weakening Gulf low will tend to keep conditions unsettled at times for Southeast Alaska with periods of mainly light rain expected. At this time, it appears likely that the heaviest rainfall should be south of the Mendenhall Glacier, which is being monitored for potential downstream flooding. Heavier rain is likely for portions of the Alaska Peninsula for Wednesday into Thursday as a moisture plume associated with the next low affects the region. There has been a general upward trend in QPF here compared to yesterday's forecast. Warm temperatures are expected across much of the Interior going into the first half of next week with an upper ridge axis in place, with highs well into the 70s and even some lower 80s, and lows generally in the 50s. A cold front drops south across the North Slope and settles in the general vicinity of the Brooks Range through the middle of the week, with a return to highs in the 40s and 50s behind it to close out the work week, and the Interior also cools down to highs in the 60s. 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