Alaska Extended Forecast Discussion National Weather Service College Park MD 548 PM EDT Sat Jun 28 2025 Valid 12Z Wed 02 Jul 2025 - 12Z Sun 06 Jul 2025 ...General Overview... A mild/stable upper level high is forecast to meander over the North Slope/Brooks Range mid/late week and eventually slip southeastward into the Yukon by next weekend. Between 50-55N, a few systems will traverse this latitude band which will keep the highest rain chances across the Aleutians and into the Panhandle. This pattern will be conducive to enhanced thunderstorms over the interior which may spark some fire concerns. ...Guidance Evaluation/Preferences... The 12Z model guidance suite was in good agreement overall with the handling of the synoptic features, with expected detail differences through the period (timing/track/strength). The ECMWF AI/ML models/ensembles were close to the dynamical consensus that included the 12Z GFS/ECMWF/UKMET/Canadian. Though differences are less than average, it was evident that the AI models/ensembles were notably north of the dynamical models with the track of the late week upper/sfc low (by perhaps 5deg latitude) perhaps due to the strength of the upper high to the north. Favored the stronger upper high solution which would keep the storm track a bit farther south. The ensemble means were gradually increased to about 40% weighting by next Sat/Sun to account for deterministic spread. ...Weather/Hazards Highlights... The upper high will promote mild/warm temperatures with isolated showers/storms for the North Slope/Brooks Range and much of the interior to start, with temperatures rising into the 80s in the warmest spots. Over the Tanana Valley, thunderstorm chances may increase by later in the week as anomalous easterly flow around the upper high increase instability when combined with warm/very warm surface temperatures. Thunderstorms without much rainfall could lead to fires started by lightning. More stratiform rain will be favored across the Aleutians and into the Panhandle (as well as skirting coastal Southcentral) as the Bering-Gulf systems move through from west to east. Rainfall amounts will be light to modest and temperatures will be near to a bit below normal due to the cloud cover. 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