Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 511 PM EST Sat Mar 08 2025 Valid 12Z Wed Mar 12 2025 - 12Z Sun Mar 16 2025 ...Guidance Evaluation and Preferences... Prefer a composite of best clustered model guidance from the 12 UTC ECMWF/UKMET/Canadian valid for Wednesday-Friday of next week in a pattern with good ensemble support and seemingly overall above normal predictability. Forecast spread is greatest with progression of upper low energy working into the Interior from northwest Canada, with no clear resolution. To the south, the 12 UTC GFS is slower to transfer energy downstream toward the Gulf of Alaska in this period, contrary to WPC continuity and bias correction. Forecast spread increases into next weekend, lending guidance preference towards the ensemble means. However, a common trend toward flow amplification at mid-upper latitudes may favor greater weighting toward the less progressive ECMWF ensemble mean. ...Weather/Hazards Highlights... Guidance offers varied timing/path differences, but most show a conduit to bring Northwest Canada upper trough/low energy gradually and generally westward across the Interior through next week that could squeeze out some local snow showers in a slowly cooling pattern. Pressure gradients underneath a lingering Arctic high could result in enhanced winds, especially over the Northwest/North coasts and favored inland terrain. Farther south, leading upper trough/low energy and an associated eastern Gulf of Alaska surface system offers modest precipitation potential for southern/southern coastal Alaska into next midweek before exiting/losing influence. Upstream, a sprawling low pressure system remains slated to likely organize and track to the south of the Aleutians Wednesday/Thursday to enhance winds before sliding offshore over the Gulf of Alaska/Northeast Pacific Friday/next weekend as mainly a maritime hazard. Expect periods of generally light precipitation on the northern periphery of the storm into coastal SouthCentral/Southeast Alaska. Guidance signal is growing in support of another deepened low pressure frontal system back toward the Aleutians next weekend to monitor, especially given upper flow amplification. Schichtel 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