Alaska Extended Forecast Discussion National Weather Service College Park MD 748 PM EDT Thu Sep 11 2025 Valid 12Z Mon 15 Sep 2025 - 12Z Fri 19 Sep 2025 ***Heavy rain likely for southern and southeast Alaska for early next week as Gulf low approaches*** ...Overview... The beginning of next week is expected to be rather unsettled across the Gulf Coast from the Kenai Peninsula to southeast Alaska as a storm system moves in from the southwest. This low weakens by midweek as attention then turns to the central and western Aleutians with the next low pressure system developing over that region, and this should track in the general direction of southwestern mainland Alaska by next Thursday. ...Guidance Evaluation/Preferences... The guidance has a decent overall handle on the general weather pattern to begin next week, although the GFS is farther to the northeast than the model consensus with the weak low near the Arctic Coast. Meanwhile, the non-NCEP guidance is generally east of the GFS/GEFS with respect to the Gulf low Monday into Tuesday. Looking ahead to mid-week, the EC/ECENS is faster with the low near the Aleutians, and the CMC is stronger with an arctic low for the end of the week. Today's WPC forecast is about 100 miles or so farther south with the Gulf low compared to yesterday's forecast on Monday. There has also been a slight northward trend with the Aleutians low with today's forecast. A general deterministic model blend was employed to start with on Monday, followed by gradually increasing the ensemble means to about half by next Friday. ...Weather/Hazards Highlights... An organized low pressure system is likely to bring gusty winds and periods of moderate to heavy rainfall to portions of the Kenai Peninsula, South-central mainland, and Southeast Alaska early next week. This should reach peak intensity on Monday, which is when the frontal system should arrive along the Gulf Coast. The low should weaken going into Tuesday night and Wednesday, with a corresponding abatement in precipitation. Rainy conditions and gusty winds then affect the Aleutians and the Alaska Peninsula by Wednesday into Thursday. Temperatures will likely be average to above average across the central to eastern Interior, and likely below average over the West coast beneath the upper trough. 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