Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 648 PM EST Fri Jan 31 2025 Valid 12Z Tue Feb 4 2025 - 12Z Sat Feb 8 2025 ...Synoptic Overview... The main theme for the extended forecast period will be a negative EPO pattern featured by a strong mid-upper level ridge axis extending north from the Gulf and across the mainland. This should initially be a closed upper high near the Alaska Peninsula on Tuesday and this slowly sinks to the south through the end of the week, with the core of the ridge over the central Gulf by Friday. Meanwhile, shortwave energy and accompanying surface lows are expected to track around the western periphery of that ridge and cross the central/western Aleutians into the Bering Sea. This synoptic set-up will tend to maintain above normal temperatures and mostly dry conditions across the majority of the state through next Saturday. ...Guidance Evaluation and Preferences... The 12Z model guidance agrees well on most facets of the forecast to begin the period Tuesday, with the best agreement on the strength and position of the main upper ridge across the state. The region with greatest uncertainty moving forward is across the western portion of the domain to include the Aleutians and the Bering Sea where the main storm track will be. The ECMWF and GFS are among the stronger solutions with a storm system crossing the Aleutians Thursday, but things become more uncertain with shortwave energy behind that, with the ECMWF/CMC portraying a stronger second low in contrast to a weaker GFS solution. By next Saturday, there is still good overall model support for the ridge axis extending north across the mainland, although the ensemble means are a little west with the ridge axis compared to the deterministic guidance. Much greater uncertainty resides across the Bering and North Pacific however. The ensemble means were increased to about half by the Friday/Saturday time period. ...Weather/Hazards Highlights... The weather is forecast to be relatively pleasant for this time of year with the upper high/ridge and surface high governing the overall weather pattern. The southern half of the state is expected to be mainly on the dry side and offshore flow along the southern coastal areas should keep precipitation coverage greatly reduced. There may be an increase in showers across portions of the Alaska Peninsula and eastern Aleutians as the storm track gradually moves farther east, with most of the rainfall confined to the central Aleutians and offshore areas. There may be some light snow or mixed precipitation across portions of northwestern Alaska through the middle of the week. Temperatures are expected to be pleasant by early February standards across the mainland and especially so across the North Slope and Brooks Range with highs potential running 30 degrees above seasonal averages. A few record highs are within the realm of possibility. A slight cool-down is probable going into the end of the week, but still above normal in most cases. There may be some Interior valleys that have surface inversions that don't mix out, and those areas would still remain rather cold. The Southeast Panhandle region should also be colder than average most days with an arctic surface high situated over southwestern Canada. Hamrick 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