Alaska Extended Forecast Discussion National Weather Service College Park MD 753 PM EDT Sun Jul 13 2025 Valid 12Z Thu 17 Jul 2025 - 12Z Mon 21 Jul 2025 ...Guidance Evaluation and Preferences... The 12Z model guidance generally features good agreement across the Bering Sea and extending east to the mainland for the beginning of the forecast period Thursday. However, there continue to be greater than normal differences with the weakening low pressure system near the Alaska Peninsula and northern Gulf. The 12Z GFS and UKMET in particular were stronger and maintained the low longer, whereas the ECMWF and CMC were weaker and more in line with the AIFS and ensemble mean guidance, so the forecast was hedged in that direction. The 18Z GFS trended towards the preferred model blend and weakens the low quicker. Looking ahead to next weekend, the CMC is farther east with the main Bering Sea low, whereas the ECMWF is stronger and to the west. The guidance then suggests the low could split into two separate lows with triple point low evolution south of the Aleutians potentially. The guidance then suggests an upper ridge axis builds across the Gulf going into next Monday. The ensemble means were gradually increased to about 2/3rds by that time. ...Pattern Overview and Weather/Hazards Highlights... A mild weather pattern will continue across mainland Alaska through the middle to end of the week, and also into next weekend with a weak upper ridge in place and a weakening low pressure system over the Gulf. Scattered showers and thunderstorms are likely to develop during the afternoon and evening hours across much of the Interior midweek with moisture advecting northward across the state. There may be an increase in rain and wind for portions of southwestern Alaska for the end of the week, but currently does not appear to be a hazards level event. This would also help to disperse more of the wildfire smoke across western portions of the state. For the southern coastal areas, on and off showers are likely through the upcoming week, but not a wash-out. The heaviest rainfall would be for the windward terrain of the coastal mountain ranges. Temperatures will likely be in the 70s to around 80 degrees for inland areas south of the Brooks Range, and 50s and 60s for the coastal areas. Hamrick Additional 3-7 Day Hazard Information can be found on the WPC medium range hazards outlook 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