Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 715 PM EDT Mon Mar 15 2021 Valid 12Z Fri Mar 19 2021 - 12Z Tue Mar 23 2021 ...Overview and Guidance/Uncertainty Assessment... Troughing in the Gulf/Panhandle region on day 4 (Friday) will give way to a brief period of ridging before another couple of storm systems move from the Aleutians into the Gulf this weekend and into early next week. This results in a more amplified pattern the second half of the period with deep troughing across the mainland/Gulf region and ridging through much of the Bering Sea. There remains relatively good clustering between the latest cycle of guidance through the period, with the normal timing and intensity differences increasing later in the period. The WPC blend relied on majority (70 percent) operational guidance (12z GFS/ECMWF) through day 6, increasing contributions from the ECENS/GEFS means day 6 and 7 to mitigate late period differences. This also maintains good continuity with the WPC CONUS progs downstream. ...Weather/Hazards Highlights... With the waves of low pressure approaching the southern Mainland and the Panhandle, these areas could have periods of scattered to widespread precipitation. A majority of the Mainland will be mostly quiet and dry. Various systems will also bring mainly scattered precipitation to the Aleutians, with coverage increasing across the western islands by the end of the period as a cold front moves into the Bering Sea. Most of the region will have temperatures below average, especially the second half of the period, with daytime highs averaging 10-20 degrees below normal. Santorelli No significant hazards are expected over Alaska during this forecast period. 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