Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 644 PM EDT Sat Mar 28 2020 Valid 12Z Wed Apr 01 2020 - 12Z Sun Apr 05 2020 A relatively progressive weather pattern appears set to evolve across Alaska and the North Pacific during the extended forecast period. A strong upper-level jet along the northern periphery of a building upper-level ridge axis near the date line and along the southern periphery of a broad region of cyclonic flow across eastern Siberia will result in an increasingly active storm track across the Bering Sea. The evolving pattern will also lead to a very gradual warming trend, with initially well below average temperatures across portions of southern/eastern mainland Alaska slowly moderating at least a bit closer to seasonal norms through the mid to latter portion of next week (but perhaps remaining slightly below normal). A leading frontal system should bring precipitation and gusty winds to the Alaska Peninsula Wed-Thu (day 4-5), while surface high pressure begins to weaken and retreat across the Interior. The GFS was the preferred solution during days 4-5, as it has shown perhaps somewhat more consistency than other guidance, and also remains reasonably well-centered within the ensemble spread. By late next week, guidance shows general agreement that a relatively deep low pressure system should take shape in the Bering Sea. Deterministic solutions show typical variability for the time range with respect to timing, structure, and intensity of the system. Consensus among ensemble means is much better, however, with the ECENS/GEFS/NAEFS all showing a low deepening across the western Bering Sea Thu night-Fri, and either approaching the Bering Strait (per the ECENS) or northwestern mainland Alaska (GEFS/NAEFS) next Sat-Sun. In either of these scenarios, the surface front south of the low would bring increasingly widespread precipitation across the Aleutians and into the western half of mainland Alaska through next weekend, with some potential for strong gusty winds for coastal locations. Given the increased spread after day 5, opted to lean much more heavily toward ECENS/GEFS ensemble means for days 6-8 (Fri-Sun). Ryan Additional 3-7 Day Hazard information can be found on the WPC medium range hazards 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