Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 756 PM EDT Sun Jul 28 2024 Valid 12Z Thu Aug 1 2024 - 12Z Mon Aug 5 2024 ...General Overview... The slow moving upper low north of eastern Siberia will likely lift northeastward across the Arctic Ocean for the end of the week, leaving an upper trough situated over the northern half of the state. By next weekend a more organized upper trough and cold front will likely cross the Bering Sea with a downstream upper ridge trying to develop across eastern mainland Alaska, leading to gradually warmer conditions. A lingering trough over the Gulf region will likely keep some showers around for the southern coastal areas. ...Guidance Evaluation/Preferences... The 12Z model guidance suite has good overall agreement on the synoptic scale pattern for the end of the week across the Alaska mainland, and some minor timing and placement differences with the upper trough and weak surface low over the Gulf. Looking ahead to Saturday, the GFS becomes a slower solution with the trough crossing the Interior, whereas the ECMWF is faster than the middle ground CMC and UKMET solutions. Meanwhile over the Gulf, the GFS and to a lesser extent the CMC are quicker to bring a surface low towards the coast, whereas the ECMWF holds it back well to the south. Models are trending towards a stronger upper trough and resultant surface low over the Bering by late Sunday and into Monday, with the GFS on the western side of the guidance. The forecast was primarily based on a multi-deterministic model consensus through Friday, and then gradually transitioning to about 40% ensemble means by next Sunday/Monday. ...Weather/Hazards Highlights... A gradual moderation trend is expected in terms of temperatures going into next weekend as the pattern over the state becomes more amplified and southwesterly flow aloft ushers in a warmer air mass by Sunday into Monday. Highs are expected to reach into the middle 60s to middle 70s across most of the Interior, after relatively cool conditions this week. Areas of moderate to locally heavy rainfall can be expected for western portions of the Brooks Range late in the week, and perhaps again by next Monday. Terrain enhanced showers can also be expected for the southern coastal areas, but nothing too heavy. Depending on the evolution and proximity of the incoming Bering Sea low pressure system, breezy to windy conditions could develop for the western mainland, especially near the coast. There may also be enhanced rainfall ahead of this Bering low given some tropical moisture potentially be advected northward. 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