Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 639 PM EDT Thu Jun 24 2021 Valid 12Z Mon Jun 28 2021 - 12Z Fri Jul 02 2021 ...Unsettled weather expected from portions of the Aleutians to the Southern Coast... ...Overview and Guidance/Predictability Evaluation... The latest models and ensembles show very good agreement that an upper low will drift slowly eastward over or just south of the Aleutians, essentially becoming blocked by upper level ridging building over the Mainland Wednesday-Friday. Perturbations rounding the base of the trough will send a couple of waves of low pressure/systems into the Aleutians through much of next week. Details, especially the second half of the period, become more uncertain, but models have trended in the direction of a stronger/deeper low affecting the Aleutians while upper ridging across the state may hold off a few days as troughing moves quickly from Alaska into western Canada by mid-week. To mitigate the smaller scale, less predictable, features, WPC trended towards a 50/50 model/ensemble blend by day 8. The first half of the period leaned very heavily on the 12z operational model runs (GFS/ECMWF/CMC). ...Weather/Threats Highlights... Surface lows and fronts ejecting into the Aleutians next week is expected to set up a wet and windy pattern from especially the eastern Aleutians into the Alaska Peninsula and parts of the Southern Coast. This should bring at least moderate rainfall to the region, although exact amounts remain uncertain. Gusty winds will also accompany these systems as they cross the region. In terms of temperatures, upper troughing across the state Monday and Tuesday will keep temperatures cool, especially across the Brooks Range and northern Slope region where daytime highs as much as 20 degrees below normal are possible. As upper level ridging builds over the state during the later half of next week, temperatures should warm to modestly above normal, with pleasant highs in the 70s for parts of eastern Alaska. Southern Alaska and back to the Aleutians should remain near or below normal underneath cloudy skies and unsettled conditions. Santorelli 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 Hazards: -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