Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 510 PM EDT Tue Jun 29 2021 Valid 12Z Sat Jul 03 2021 - 12Z Wed Jul 07 2021 ...Unsettled weather expected from portions of the Aleutians to the southern Coast... ...Overview and Guidance/Predictability Evaluation... The guidance shows reasonably good agreement on the movement of a deep cyclone from near the Aleutians/Bering Sea eastward into the far north Pacific/near the Gulf of AK. There are detail issues, with the 12z Canadian bodily moving a deeper surface low from south of the Aleutians into the northeast Pacific late in the period. Per coordination with Anchorage, it seems more likely that a new low would form as the mid-level system shifts eastward. The 12z GFS/12z ECMWF also appear to be breaking down the top of the amplified ridge just northeast of AK too much. The pressures, fronts, and 500 hPa heights used a compromise of the 00z UKMET, 00z Canadian, 12z GFS, 12z ECMWF on late Friday before slowly substituting in the 12z NAEFS and 00z ECMWF ensemble means for the UKMET and Canadian solutions. The remainder of the grids are more evenly weighted to the deterministic and ensemble mean guidance through the period. ...Weather/Threats Highlights... Unsettled weather will shift across the AK Peninsula and Kodiak island into south-central AK and eventually southeast AK with periods of showers and breezy conditions as a low and its attendant fronts move through. Moisture should also extend northward into parts of the western mainland bringing rainfall to the region during the weekend. As upper level ridging is slow to erode across eastern Alaska, especially the first half of the period, east-central AK should be the warmest with highs in the 70s. Elsewhere across Alaska should be near or below normal underneath increasingly/mostly cloudy skies and upper level troughing. Roth 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