Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 423 PM EDT Fri Jul 12 2019 Valid 12Z Tue Jul 16 2019 - 12Z Sat Jul 20 2019 The forecast period begins on Tuesday with an elongated upper low situated over the northern Gulf of Alaska and a general ridge axis stretching from the Bering Sea to the Northwest Territories. The trend in the guidance has been for this upper low to track eastward a bit quicker across the northern Gulf region, with an upper level trough lingering behind across the Aleutians. By late in the week, a potent upper low north of the Arctic Coast should support the development of an occluded surface low and be strong enough to push a cold front across much of the central and northern part of the state by next weekend. The greatest model differences reside across the north Pacific, with the GFS indicating a much greater degree of upper level ridging across the Aleutians, whilst the CMC, ECMWF, and even the ensemble means support lower heights aloft. The forecast was weighted more heavily towards the ECMWF and the EC mean, with some of the GFS and CMC included as well. Scattered showers and a few thunderstorms will be possible through much of the forecast period, particularly across the Interior and over the higher terrain. Given the abatement in the strength of the upper ridge, temperatures will be cooler than those observed in recent days, and below average readings will be possible by the end of the forecast period if the cold front makes enough southward progress across the state. Hamrick 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