Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 652 PM EDT Thu Oct 27 2022 Valid 12Z Mon Oct 31 2022 - 12Z Fri Nov 4 2022 ***High winds across the Alaska Peninsula/Kodiak Island and heavy precipitation over the Panhandle will continue into Monday with a strong low*** ...Overview... The weather pattern is expected to remain rather active across the southern portions of the state for next week. A gradually weakening surface low over the northern Gulf region will likely continue to produce strong and gusty winds from the Alaska Peninsula to the southern mainland coast on Monday, and some lingering moderate precipitation across the southeast Panhandle. Going into mid-week, a phasing of two separate storm systems (one over the northern Bering and the other south of the Aleutians) will likely result in a single and stronger storm that could affect portions of western Alaska with heavy precipitation and gusty winds, and a new low could develop over the northern Gulf by the end of next week. ...Guidance/Predictability Assessment and Preferences... Model guidance remains in generally good agreement with the strong surface low centered over the eastern Gulf of Alaska on Monday, with only minor differences in the placement and strength, followed by steady weakening. Farther upstream, a closed upper low is becoming more likely over the Bering Sea around by early Tuesday coupled with a surface low there. But farther south across the Aleutians and Pacific, while there is general agreement for troughing, more noteworthy differences in shortwaves and in surface lows exists. There is a decent signal in the guidance for a low pressure system south of the Aleutians to phase with the Bering Sea low and consolidate into a stronger storm system, with the 12Z GFS among the strongest and farthest west solutions, although the ECMWF is also quite strong by Tuesday night. However, other guidance, such as the JMA, ICON, and CMC, are much weaker with the low that develops, so the forecast is likely to change substantially with future updates. The WPC forecast was based on a blend of the GFS/ECMWF/CMC/WPC continuity early in the forecast period given the reasonable agreement early in the week. With more forecast uncertainty going forward, the forecast incorporated more of the GEFS and EC ensemble means and gradually increased their weighting to about half by Thursday/Friday. ...Weather/Hazards Highlights... The Gulf of Alaska low will be the main player causing significant weather on Monday. The tight pressure gradient with the low will cause concerns for strong winds across the Alaska Peninsula as well as Kodiak Island, and as the low pulls away, northwesterly flow could cause some gap wind issues in some of the same areas through Monday evening. Some gusty winds are possible for the Panhandle as well but probably less significant. After that, there are likely to be some wet and probably windy intervals across the Aleutians for the first half of the work week with the North Pacific storm system, but there remains considerable uncertainty with the details for now. However, the general trend should be for precipitation to shift eastward mainly across southern Alaska through midweek and beyond as the trough moves east. Below normal high temperatures should persist over a majority of the state including the Panhandle through the period, with the greatest anomalies over southern areas. Locations near the northern coast of the mainland will likely remain closer to normal. Low temperature anomalies may overall be more moderate, but still below average over most areas except for the North Slope. The Panhandle may see a mix of above/below average lows depending on location and day. Hamrick/Tate Hazards: - Heavy precipitation across portions of the Alaska Panhandle, Sun, Oct 30. - High winds across portions of southern mainland Alaska, Sun-Mon, Oct 30-Oct 31. Additional 3-7 Day Hazard Information can be found on the WPC medium range hazards outlook 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