Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 252 PM EDT Mon Jun 10 2019 Valid 12Z Fri Jun 14 2019 - 12Z Tue Jun 18 2019 ...Guidance/Predictability Assessment... The WPC Alaskan medium range product suite was mainly derived from a blend of the 12 UTC GFS/GEFS mean, 00 UTC ECMWF/ECMWF ensemble mean, and the National Blend of Models. Applied greater blend weightings to the deterministic models day 4/5 to provide detail consistent with above normal predictability. Forecast spread remains manageable, but gradually increases through later period. This supports increasing ensemble weightings day 6-8 in a pattern with closer to average uncertainty. This solution maintains reasonable WPC forecast continuity. ...Pattern Overview and Weather/Threats Highlights... Models/ensembles have been in general agreement in principle with a slow pattern evolution for the past several cycles. Two slowly moving upper lows to the north and south of the mainland favor weak ridging with generally warm and benign weather over the interior through this forecast period. In this patern a closed mean trough will meander over the Arctic and force settlement of a trailing/cooling front down over the North Slope. Well underneath...a closed mean system stalls and reforms just south of the Alaskan Peninsula and eastern Aleutians days 4-8 with precipitation/windy/unsettled conditions spreading across the region and modestly downstream into Southwest and Southern coastal Alaska. This system will also offer a prolonged maritime hazard. Schichtel 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