Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 610 PM EDT Sun Jul 07 2024 Valid 12Z Thu Jul 11 2024 - 12Z Mon Jul 15 2024 ā€Multi-day heavy rain pattern from West/Southwest through Southern Alaskaā€ ...Overview and Guidance Evaluation/Preferences... Forecast spread has decreased through medium range time scales, bolstering forecast confidence given larger nature of main weather focusing systems with time. Prefer a blend of best clustered guidance of the 12 UTC GFS/ECMWF and GEFS/ECMWF/Canadian ensemble means with emphasis on the GFS/ECMWF valid Thursday/Friday increasingly shifting to the ensemble means next weekend/Monday along with manually applied edits to better depict surface systems with favorable mean upper support as an offset to inherent smoothing from a blending process. ...Weather/Hazards Highlights... A slow moving surface front may linger across the Interior and provide a weakening focus for local precipitation next week. Much of the rest of Alaska should remain quite wet and unsettled, which should also help bring some relief to wildfire activity. Despite guidance variances recently, models and ensembles continue to show an amplified and slowly evolving larger scale pattern with a major closed upper low/trough centered over the Bering Sea and an emerging upper trough over the Gulf of Alaska as ample energy fuels cyclogenesis and frontogenesis. In this scenario, heights rise at least temporarily overtop into the eastern Interior to moderate short range cooling before retreating. Around the periphery of the ridge, this pattern favors a continued wet and storm system active period out from the Arctic Ocean to the Bering Sea, with inland impacts from West/Southwest Alaska through the Alaska Peninsula/Kodiak Island, SouthCentral and then Southeast Alaska later week through next weekend. Storm systems will remain prone to develop and evolve/linger over the eastern Bering and downstream into the Gulf of Alaska. This portends a protracted period with potential for cummulative heavy rain, with some 1-2"+ daily totals set to steadily add up over the course of this forecast period to monitor for any runoff issues, especially over favored terrain. Schichtel 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