Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 634 PM EDT Thu Jun 25 2020 Valid 12Z Mon Jun 29 2020 - 12Z Fri Jul 03 2020 ...Overview and Weather/Hazard Highlights... Heights are forecast to gradually rise across Alaska during the extended period as an initially deep upper low centered over the Bering Strait gradually weakens and breaks apart. One component of this system is forecast to move east across mainland Alaska along with a weakening surface front Tue-Wed and perhaps into Southeast Alaska by Thu as an upper low, generating unsettled/showery conditions across those areas as it passes. Elsewhere, a low pressure system crossing the North Pacific is forecast to enter the southern Bering Sea on Wed, with the associated front sweeping east across the Aleutians through Fri, with another similar system following quickly behind it. Showery conditions along with gusty winds should accompany these system across the Aleutians, and perhaps into portions of the Alaska Peninsula by next Friday. As the northern extent of an upper ridge slowly builds north into Alaska next week, initially below average temperatures should begin to gradually warm. High temperatures are forecast to be 10 to 15 deg F below average across much of mainland Alaska over the weekend, with temperatures gradually inching closer to seasonal norms toward the middle of next week (particularly close to the coast). ...Guidance/Predictability Assessment... The 12Z GFS was used heavily early in the forecast period, with emphasis quickly shifting toward an ensemble mean-heavy (ECENS/GEFS) blend by day 6 (Wed) and continuing through day 8 (Fri). The GFS was generally representative of the overall guidance consensus on day 4 (Mon) with the system approaching the Aleutians and with Bering Strait upper low that begins to break down. After that, timing/intensity differences generally increase across the board, making any deterministic solutions not particularly useful alone from day 6 onward - hence the short to more emphasis on the ensemble means. 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 Hazards: 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