Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 712 PM EDT Tue Jun 25 2024 Valid 12Z Sat Jun 29 2024 - 12Z Wed Jul 03 2024 ...Overview and Guidance Evaluation/Preferences... The ensemble means from the GEFS, EC, and CMC appear in good to excellent agreement on the evolution of the upper-air pattern across Alaska through the medium-range period. In this Rex Block configuration, an upper ridge will have a tendency to close off across the northern half of Alaska while an initially deep Bering Sea low weakens and slides under the ridge toward the Gulf of Alaska early next week. The EC mean, particular the 12Z run, is showing a faster ejection of the weakened upper low across the Gulf of Alaska early to middle of next week in better agreement with the faster GEFS mean. The latest CMC mean also shows a faster motion for this low while building a stronger ridge behind the low over the Aleutians. With a major network outage continuing at NCWCP, no 500mb charts for Alaska were created today. Surface prognostic charts were created after some modifications to yesterday's charts with manual creation of the Day 8 isobars and fronts. The hemispheric charts were not created either. The Alaskan grids are to be created from an auto script at 23:05Z. Whether these grids will be successfully sent out remains to be seen. ...Weather/Hazards Highlights... This pattern will favor the Aleutians and AK Peninsula to be rainy, as the lingering Bering Sea cyclone gradually slides across the Aleutians reaching into the Gulf of Alaska by early next week. The double-barrel system will allow for modest rainfall in its vicinity. Winds should generally peak in the 30 kt (35 mph) range at times across the Arctic Coast and coastal areas. The terrain in south-central and northern AK are expected to have the best chance of showers and thunderstorms. There is the possibility of dry lightning strikes during the afternoons and evenings which would increase the risk for fire weather concerns given the dry fuels across the region. Ridging across the Mainland will maintain warm to hot temperatures. Afternoon maximums should lie the 80-90F range for the most part across the eastern interior sections. Highs mostly in the 60s and 70s are expected across lower elevations of south-central AK, with mainly 50s and 60s in most coastal areas, 50s and 40s across the North Slope, and mid to upper 40s in the Aleutians. The North Slope will be cool overnight with lows in the 30s, while highs will approach 60 degree not too far inland from the shore. Higher elevations in the terrain across south-central and southeast AK should fall below freezing overnight. Kong/Roth 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