Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 339 PM EDT Thu Oct 31 2019 Valid 12Z Mon Nov 04 2019 - 12Z Fri Nov 08 2019 Upper ridging over the Gulf, western Aleutians, and northeastern Russia/Bering Strait will consolidate into northwestern Alaska midweek next week, favoring troughing to its southwest and south. The models/ensembles were in good agreement through the period on the longwave pattern but differed in the smaller wavelength features. A varying multi-model/ensemble blend among the 12Z GFS/00Z ECMWF and the 06Z GEFS mean/00Z ECMWF ensemble mean was used as a starting point. 00Z ECMWF was not preferred for Tue-Wed as it seemed too aggressive with a small upper low moving through the interior where the majority suggests fervent ridging. 12Z GFS was weaker and preferred. By next Thu/Fri, GFS appeared too progressive and too far south with the elongated occluded system south of the Gulf. Favored the 00Z ECMWF here and across the mainland as the lead-in feature moved out of the region. ECMWF ensemble mean was preferred over the GEFS mean for its better definition. On Monday, system south of the central Aleutians will spread rain/snow over the Aleutians into southwestern Alaska before sliding eastward across Southcentral. In the western Bering, a system will pass through the western Aleutians late Tuesday and track southeastward as its triple point takes over and reforms south of the AkPen. This will limit rain/snow to mainly coastal and near-inland areas from the Aleutians and across Kodiak Island, attempting to move northward by next Fri, depending on the strength of the ridging to its northeast. Temperatures will remain near to above average over much of the state, especially the North Slope, with the exception over the Panhandle. High pressure (higher than 1040mb) will slide southeastward through the NW Territories of Canada and funnel cooler temperatures through the region on easterly flow. Fracasso 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 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