Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 758 PM EDT Thu Oct 3 2024 Valid 12Z Mon Oct 7 2024 - 12Z Fri Oct 11 2024 ***Heavy rain and mountain snow expected for the south coastal areas for the beginning of the week, and strong winds over the Gulf waters*** ...Overview and Guidance Evaluation/Preferences... The powerful extra-tropical low associated with former typhoon Jebi will likely be over the northern Gulf of Alaska by the beginning of the forecast period Monday, after hammering the Aleutians and western portions of the mainland over the upcoming weekend. It is forecast to weaken by Monday with central pressure rising to about 980-990 mb, and then weakening further going into Tuesday and beyond. A secondary low may develop east of the primary low and track in the general direction of the southeast Panhandle on Tuesday, and then likely a break in the bad weather for Wednesday into Thursday. There may be additional trouble on the distant horizon as another potentially strong storm system develops south of the Aleutians by the end of next week. The 12Z model guidance suite has a decent overall depiction across the Alaska domain to begin the work week, although the ECMWF is stronger with the potential triple point low that heads towards the Alaska Panhandle region. The CMC strays from the consensus for the middle of the week with an organized low pressure system that is not reflected in the GFS or ECMWF guidance, but it does agree better with the stronger low near the Aleutians by Friday. Ensemble means were gradually increased to about 40-50% by the Thursday/Friday time period. ...Weather/Hazards Highlights... Gale to storm force winds and extremely rough seas are expected over the open waters of the Gulf of Alaska to begin the week, with strong winds likely across the Alaska Peninsula and Kodiak Island, with gap wind enhancement. Heavy rainfall (and snow in the higher terrain) is expected from the Alaska Peninsula all the way to the southeast Panhandle, with a potential atmospheric river event to the east of the main surface low that could produce several inches of QPF during the Monday-Wednesday time period. Depending on the evolution of the next storm over the Gulf late in the period, heavy precipitation could make a return next Friday for some of those same areas. In terms of temperatures, cooler than normal highs are likely over southern parts of Alaska owing to increased cloud cover and precipitation, and warmer than normal temperatures are likely for the northern two-thirds of the mainland for the upcoming week. 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