Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 714 PM EDT Mon Jul 01 2024 Valid 12Z Fri Jul 05 2024 - 12Z Tue Jul 09 2024 ...Overview and Guidance Evaluation/Preferences... The guidance continues to show good agreement on the large scale pattern featuring an upper low drifting westward north of Alaska and interacting with and eventually combining with a shortwave through eastern Russia. As a blocky ridge builds south of the Aleutians and eventually into the Bering Sea next weekend, a fairly deep upper low will form over/near the Bering Strait and likely drift southward over the northwest Mainland. The CMC was a little bit faster/farther south with this transition but the 12z ECMWF did trend farther south as well. Meanwhile, a deep upper low will meander south of the Gulf of Alaska late this week before slowly drifting north towards the southern coast/Southeast Alaska. The 12z ECMWF is much farther east/faster with this and seems out of line with the better consensus. The WPC blend for today favored a majority blend of the GFS and ECMWF through the first half of the period, transitioning to 50-70 percent ensemble means (with some GFS) late period to mitigate the bigger differences late period. Overall, this maintained good continuity with yesterdays forecast as well. ...Weather/Hazards Highlights... Upper level troughing and a surface front should provide some focus for moderate to locally heavy precipitation across much of central to northern Alaska late this week. The heaviest rainfall is expected across the eastern Interior, and this may bring some relief to the spreading wildfires across Alaska currently. By the weekend, rain and storms will increase in coverage and intensity across Southern portions of the state as Gulf moisture gets pulled northward around the deep upper low in that region. Northern to western parts of Alaska will stay wet and unsettled through the weekend and into early next week. Southeast Alaska looks dry through the weekend, but rainfall may increase again by early next week as the upper low over the Gulf gets pulled northward. Given overall upper troughing over the state much of the period, daytime highs across nearly all of Mainland Alaska and into the Southeast will be well below normal, with the greatest anomalies across western and northern parts of the state. Santorelli 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