Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 700 PM EST Wed Feb 23 2022 Valid 12Z Mon Feb 28 2022 - 12Z Fri Mar 04 2022 ...Overview... A relatively mild pattern is forecast for Alaska during the first half of next week, as southerly flow dominates in between an upper low moving slowly across the Kamchatka Peninsula and ridging with an axis over northwestern Canada that could migrate into Alaska around Thursday of next week. Above average temperatures and periods of light to moderate precipitation are expected for coastal areas with this pattern. ...Guidance/Predictability Assessment... Recent model and ensemble guidance is generally agreeable with the pattern described above, but ample differences remain with the smaller scale details, including surface and upper lows over the northern Pacific and Gulf of Alaska for the early part of next week. A multi-model deterministic blend yielded a surface low position west of the Panhandle early Sunday, closest to the ECMWF/UKMET position. Additional low pressure and frontal systems move across the northern Pacific/Gulf during the period, with a general trend for faster tracks of the fronts compared to the previous forecast, but once again confidence is low with the details. Most guidance shows a bout of ridging briefly building over the Aleutians next Monday into Tuesday, shunting eastward ahead of the larger scale Kamchatka to Bering Sea upper low. At the surface, preferred the ECMWF and CMC that were better clustered with the ensemble mean positions of a surface low in the western Bering, whereas the GFS runs are alone in showing the low over the Aleutians early Tuesday. There is overall fair agreement at least in the ensemble guidance that upper ridging may build over the eastern mainland by the end of the period Thursday ahead of the low/trough to the west, possibly combining the ridging influences that tracked across the Aleutians and northwestern Canada. A surface low associated with the upper low/trough slowly making its way eastward across the Bering/Aleutians is then likely to affect the Aleutians Thursday, which had okay clustering especially in the ensemble means, with the ECMWF the closest deterministic model to the low position. Given the deterministic model differences, phased in the ensemble means to around 50 to 70 percent of the forecast blend by days 7-8. ...Weather/Hazard Highlights... Moist southerly flow is forecast to keep rain and snow chances in the forecast particularly across coastal areas. Precipitation could be enhanced over the Panhandle over the weekend with the possibility for a lingering low pressure system, but with light to perhaps locally moderate amounts, generally trending lighter with time. Some light scattered precipitation could extend farther north over the mainland as well. Increasing precipitation and possibly gusty winds are then forecast for the Aleutians through much of the workweek, with amounts and timing depending on low pressure/frontal systems. Current forecasts show the best signal for notable precipitation there by around next Wednesday-Thursday. Above average temperatures will abound over Alaska through much of next week, especially for lows. The highest anomalies are forecast over the northern and western parts of the mainland for the beginning of the week, with lows up to 30-40 degrees above normal and highs 20-30 degrees above normal. Anomalies will ease with time, reaching near to slightly below average for highs in the Panhandle in the southeastern mainland by midweek, but remaining above normal farther north and west for the week. Tate No significant hazards are expected over Alaska during this forecast period. 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