Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 637 PM EDT Sat Jun 06 2020 Valid 12Z Wed Jun 10 2020 - 12Z Sun Jun 14 2020 ...Overview and Weather Highlights/Threats... A relatively progressive flow pattern is expected to persist across the North Pacific and into the Gulf of Alaska through the extended forecast period, while weak and broad upper ridging persists from the Arctic Ocean into western Canada. Meanwhile, the Interior of Alaska will lie within a region of chaotic and relatively weak easterly upper-level flow. Onshore flow across southern mainland Alaska as low pressure weakens in the Gulf of Alaska will keep the potential for precipitation up through the middle of next week (especially across the higher terrain), while weak easterly flow and occasional upper shortwave energy will also keep isolated to occasionally scattered convective activity in the picture across the Interior. A low pressure system expected to pass near the Aleutians as it moves toward the Gulf of Alaska by the middle to late part of next week will bring an increase in shower and perhaps some gusty winds to the Aleutians, with precipitation eventually increasing across the Alaska Peninsula as well. Temperatures in this pattern are expected to be above average through the forecast period, with highs ranging from 5 to 15 deg F above average for many areas, especially across the Interior. Meanwhile, more clouds and precipitation will keep temperatures several degrees below average closer to the coast. ...Guidance/Predictability Assessment... The 12Z ECMWF was used heavily early in the extended forecast period, with a gradual transition to more weight placed on ECENS/GEFS ensemble means through time through the period. Similar to yesterday, the GFS was not used this forecast cycle due to a solution that was outside consensus over a couple areas, including a system in the Gulf of Alaska by the middle of next week, and across the western Aleutians late next week. Overall, forecast confidence was was average through the extended. Ryan 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 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