Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 606 PM EST Wed Mar 05 2025 Valid 12Z Sun Mar 09 2025 - 12Z Thu Mar 13 2025 ...Deep Bering Sea Storm to bring enhanced precipitation and high winds from the Aleutians to coastal Southwest Alaska this weekend... ...Overview... A strong western Bering Sea storm will send a leading front through the Bering Sea/Aleutians, with a downstream low forming over the western to northern Gulf of Alaska Sunday-Tuesday. Guidance is split for the North Pacific/Aleutians/Bering Sea pattern into mid-later next week, but with a majority suggesting another fairly vigorous system may track toward/south of the Aleutians and AKpen. Overall these systems will tend to focus precipitation and potential for enhanced winds across the Aleutians and surrounding waters as well as parts of the southern coast, and to a lesser degree the western coast of the mainland. ...Guidance Evaluation and Preferences... Model and ensemble guidance is reasonably well clustered valid for this weekend/Monday and a composite of the 12 UTC GFS/ECMWF/Canadian/UKMET models and WPC product continuity seems to offer a solid forecast base with good detail consistent with a pattern with above normal predictability and continuity. The UKMET becomes more of an outlier from the other models/machine learning models and ensembles into Tuesday, with forecast spread and uncertainty growing rapidly through mid-later next week. Accordingly, quickly transitioned WP product guidance preference at these longer time frames to the still compatible GEFS/ECMWF/Canadian ensemble means. ...Weather/Hazards Highlights... A strong western Bering Sea storm and its leading frontal system will spread brisk to high winds (southerly ahead of the front and westerly behind) and organized precipitation across the Aleutians and surrounding waters. Some moisture and brisk winds may reach the southwestern mainland as well. An embedded developing frontal wave that should reach a position between Kodiak Island and the Kenai Peninsula by early Monday may focus some heavier precipitation in its vicinity around Sunday-Monday while lighter totals possibly extend as far east as the Panhandle. There is still a minority scenario that could lead to a farther south track of this wave and thus lower precipitation totals. Another storm potentially reaching the Aleutians around the middle of next week may produce enhanced precipitation and strong winds, but significant differences in details among guidance temper confidence in specifics at this time. Moderately below normal temperatures, more likely for daytime highs, should move across the state from west to east during the weekend and into early next week. These cool anomalies will displace warmer temperatures forecast from this week into early Saturday. Some degree of upper ridging or southerly flow aloft should favor a rebound in temperatures over the western mainland during the first half of next week while a weak upper trough/low just west of the Panhandle may keep highs below normal over that region and eastern Southcentral during the early-middle part of next week. 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