Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 311 PM EDT Tue May 28 2019 Valid 12Z Sat Jun 01 2019 - 12Z Wed Jun 05 2019 Upper pattern over the high latitudes will feature a blocking pattern with slowly moving features. On Sat 01 Jun a slowly moving upper low is forecast to be centered just south of the central Aleutians. The 00Z-06z suite of guidance (GFS/ECMWF/Canadian) clustered fairly well together and close to the ensemble means (00Z ECMWF ensemble mean and 06z GEFS Mean). The consensus of these solutions stayed close to the prior forecast/ continuity through Sunday 02 June, when the low starts to weaken and drift east. The majority of models have kept yet another upper low over Wrangel Island to the northwest of northwestern Alaska. The ECMWF weakens the initial low over the weekend while the GFS maintains it. By next week, the 00z ECMWF redevelops a low in the area. On next Tue 04 Jun the models mostly show a new cyclone developing in the northern central Pacific tot he southwest of the lower Aleutians. There are latitude differences with the 06z GFS/GEFS south of the low positions/track vs the further south ECMWF/ECMWF Ensemble Mean. There is above average agreement on the development of a low but loose clustering as to the location next Tue and Wed 05 Jun. The 12z GFS is further northeast towards the lower Aleutians Wed 05 Jun but that reflects the typical fast GFS bias, greater weighting to the 06z GEFS/00z ECMWF Ensemble means should bias correct the forecast. Temperatures will average above normal in northern AK but near to below normal across the upper Aleutians across southern coastal areas/Kenai east to the Panhandle, partly influenced by clouds and higher Pops. Rainfall will generally be light but locally moderate in favored areas in windward terrain and coastal areas of the Kenai down into the Panhandle. Petersen 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 No significant hazards are expected over Alaska during this forecast period. 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