Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 538 PM EST Mon Jan 11 2021 Valid 12Z Fri Jan 15 2021 - 12Z Tue Jan 19 2021 ...Active Weather for Southern Mainland Alaska and Southeast Alaska... ...Guidance/Uncertainty Assessment... A persistent trough over the western mainland and eastern Aleutians is forecast through much of the period while at the surface a couple strong lows will lift through the Gulf of Alaska. The first notable storm will be ongoing at the start of day 4 and is reasonably clustered with the latest guidance across the Gulf of Alaska. However, the 12Z GFS continued to be an outlier solution and was largely discounted for day 5 onward. The ECMWF/CMC idea of a faster flow across the Pacific is preferred compared to the GFS slower/blocky pattern over the Bering Sea. With this preference, another area of low pressure is possible late in the weekend into early next week. The ECENS/NAEFS was used primarily for day 7/8 which worked well with continuity. ...Weather/Hazards Highlights... For the period there is expected to be a couple of storm systems impacting portions of mainland Alaska, the first of which will be ongoing at the start of the period. Heavy precipitation is possible and some marine hazards are also possible but are expected mainly offshore. After a break for day 5/6, another deep low pressure is forecast to approach the coast and could bring with it another round of active weather including heavy precipitation. Taylor Hazards: - Heavy precipitation across portions of the Alaska Panhandle and mainland Alaska, Thu-Mon, Jan 14-Jan 18. 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