Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 309 PM EDT Mon May 27 2019 Valid 12Z Fri May 31 2019 - 12Z Tue Jun 04 2019 Upper pattern over the high latitudes will feature a slowly moving upper low from the central Aleutians eastward into the Gulf of Alaska by early next week. The 00Z suite of guidance (GFS/ECMWF and UKMET/Canadian) clustered fairly well together and close to the ensemble means (00Z ECMWF ensemble mean and NAEFS mean). The 06Z/12Z GFS were different enough that they were not used in a blended starting point, though they did not necessarily depict an unrealistic scenario. Preferred to stay closer to the larger 00Z consensus which was close to continuity. Upper low will send one main/leading front into the Panhandle on Friday then into Canada. To the north, another upper low over Banks Island/Victoria Island will attempt to drift westward but will likely get deflected by rising heights and an eventual weak closed high over the interior late this coming weekend. Models have been inconsistent in the evolution of that feature but have kept yet another upper low over Wrangel Island to the northwest of northwestern Alaska. By next week, models disagree on how to handle central north Pacific shortwaves either rotating around the upper low then likely to be south of the AkPen or along a boundary in the mid-latitudes. Either way, expect a wave to move northeastward toward the Gulf by the end of the period but perhaps not as strong as the GFS. Surface troughing will remain north of the Alaska Range with a slow increase in PoPs northward from Southcentral into the mountains and then into the Tanana Valley. Temperatures will average near to above normal north of the Alaska Range but near to below normal across Southcentral into the Panhandle with a fair amount of clouds and higher PoPs. Rainfall will generally be light but locally moderate in favored areas in the terrain and on southeast-facing coastal areas of the Kenai as well as into the Panhandle. Fracasso 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 - Heavy rain across portions of the south coast of Alaska, Thu, May 30. 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