Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 740 PM EDT Sun May 12 2024 Valid 12Z Thu May 16 2024 - 12Z Mon May 20 2024 ...Guidance Evaluation and Preferences... The 12Z model guidance suite is in good agreement on depicting an amplified trough over the Bering Sea and a downstream upper level ridge across mainland Alaska for the middle of the week. Greater differences exist across the Gulf region with a weakening trough/surface low, with the 12Z ECMWF depicting a stronger low over the Gulf that neither the model consensus nor the AIFS machine learning guidance supports. Therefore, the preference was for a CMC/GFS/UKMET/00Z ECMWF blend with more weighting towards the CMC and GFS through Friday. Going into the weekend, the guidance suggests the upper ridge near the Alaska/Yukon border will slowly break down, while a triple point low develops near the Alaska Peninsula that drifts into the northern Gulf region. The 12Z ECMWF also differs considerably with a much weaker solution compared to the other deterministic guidance, so this solution was not favored across this region. Therefore, a more ensemble mean based approach was employed for the fronts/pressures for the Sunday through Monday time period, while still keeping some of the CMC/GFS. ...General Overview and Weather/Hazards Highlights... Rain showers will likely be decreasing across southeastern Alaska on Thursday as a weakening surface low moves inland, and showers are also likely across western Alaska through Thursday as the Bering Sea low lifts north towards the Arctic Ocean, along with some gusty southerly winds. After that, the next storm system is expected to arrive Friday across the Alaska Peninsula region and bring renewed prospects for rain and mountain snow to southern Alaska. This then tracks in the general direction of the southeast Panhandle region by next weekend. Portions of south-central Alaska could get 1-3 inches of QPF over the course of next weekend, but not arising to hazards level criteria. Temperatures are generally expected to range from the mid 50s to mid 60s for most Interior locations south of the Brooks Range, and 30s/40s north of the Brooks Range. Most coastal locations in southern Alaska should generally be in the mid 40s to lower 50s. Lows will generally be in the 30s to mid 40s. 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