Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 510 PM EDT Fri Jun 07 2024 Valid 12Z Tue Jun 11 2024 - 12Z Sat Jun 15 2024 ...Guidance Evaluation and Preferences... Ensembles remain in good agreement overall with the upper pattern over the high latitudes. A respectably deep upper low in the Gulf to start the period will have already sent its front into/past the Panhandle and Interior by the start of this forecast (early Tue), but the upper low will slowly/steadily move eastward toward Hadai Gwaii by the end of next week, at a pace slightly slower than was forecast 24 hours ago by about 18-24 hours. Over the Arctic, an upper high is forecast to build southward over the North Slope by ~Thu next week and continue south-southwestward into next Fri/Sat. Finally, a system out of the north-central Pacific will attempt to push toward the western Aleutians but may get deflected eastward as it runs into the approaching upper high. This system has also trended slower in the guidance by about a day, likely related to the overall amplification of the pattern which becomes rather blocky by next week. A blend of the recent 12Z deterministic guidance sufficed for days 4-6, followed by a blend of the GFS/GEFS and ECMWF/ECMWF ensemble mean for days 7-8. This kept reasonably good continuity, albeit a bit slower in the evolution than the prior forecast. ...Weather/Hazards Highlights... Lingering moisture into eastern/southeastern Alaska early next week will mostly focus over the Interior, north of the Alaska Range, within the thermal trough. Some locally modest rainfall is possible, but the guidance QPF has trended down. Thus, the hazard areas have been removed. Breezier conditions on the North Slope Tuesday will subside as high pressure approaches. Over the Aleutians, there will be an increase in rainfall and wind to at least the westernmost islands as the system makes its closest approach around next Friday. Temperatures will be near to below normal to start the period, trending milder with time to near/above normal beneath the upper high. Fracasso 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