Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 605 PM EDT Sat Apr 08 2023 Valid 12Z Wed Apr 12 2023 - 12Z Sun Apr 16 2023 ...Cold pattern for much of Alaska next week and beyond... ...Overview with Guidance Evaluation/Predictability Assessment and Weather/Hazard Highlights... A cold closed upper low will meander over mainland Alaska through into mid-late next week underneath a rather blocky upper-level pattern across the Arctic. The demise of this system may prove slower than a composite of guidance, but system influence should weaken later next week. Expect a threat for much colder than normal conditions for western and southwest/central Alaska through midweek, moderating a bit later next week as the upper low erodes. Scattered occasional light snows are also expected from the Interior to the North Slope in this flow pattern. The overall cold to much below normal cold pattern is expected to hold for much of Alaska this April as per the Climate Prediction Center (CPC). Models and ensembles continue to show relatively good agreement on the timing and evolution of the next cyclone of concern coming into the western Bering Sea by Wednesday. The progressive approach of storm energy and lead triple-point low developments over the northern Gulf of Alaska are expected to support periods with moderate precipitation from the Aleutians through the Alaskan Peninsula/Kodiak Island and coastal South-Central mid-later next week. Surface lows with consolidate/deepen and re-develop over the Gulf of Alaska into late next week/weekend as as upper trough amplifies as further aided by northern stream energy. Expect periods of high winds/gap winds are possible in the wake of these lows to affect the Alaskan Peninsula and Kodiak Island. Unsettled weather may linger into late week/next weekend along the southern coastline of Alaska, but more so for the Southeast Panhandle as the main low position is forecast to focus/meander over the east-central Gulf of Alaska. Precipitation amounts do not appear to be excessive over the Southeast, but should be widespread and enhanced over favored terrain. Model and ensemble forecast spread has increased from yesterday, but still offer a reasonably similar pattern evolution next week in a pattern with seemingly near average overall predictability. The new differences stem mainly from varied handling of a closed upper low trough over the mainland. Prefer a blend of the 12 UTC GEFS/ECMWF ensemble means and the 12 UTC Canadian Wednesday/Thursday to show an exit of the primary mainland upper low/trough on the slower side of the full envelope of guidance solutions. Switched to the compatible 12 UTC GEFS/ECMWF ensemble means for later next week/weekend to best preserve WPC product continuity. Schichtel 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