Area Forecast Discussion
Issued by NWS Fairbanks, AK
Issued by NWS Fairbanks, AK
066 FXAK69 PAFG 142243 AFDAFG Northern Alaska Forecast Discussion National Weather Service Fairbanks AK 243 PM AKDT Fri Jun 14 2024 .SYNOPSIS... Drier and warmer conditions are expected over most of Northern Alaska this weekend into early next week. Conditions will be similar to last weekend but with much less wind. The Eastern Interior is the main area for convection through the weekend. Today expected isolated to scattered showers, and isolated to widely scattered PM thunderstorms, then just isolated PM thunderstorms Sat through Mon. Isolated dry thunderstorms are occuring today over the Northeast Interior causing Red Flag conditions in that area due to very dry conditions. A band of strong thunderstorms that stretches from the White Mountains to Chicken now will spread to Fairbanks to Northway later this afternoon and evening and to the Alaska Range by late evening. The thunderstorms will have strong gusty winds, hail up to one half inch diameter, frequent lightning and brief heavy rain. Fog along the Arctic Coast east of Utqiagvik will continue through the weekend, thinning in the afternoon and evening each day. Fog along the West Coast will continue through the weekend, thinning in the afternoon and evening each day. Surface pattern... A thermal low pressure trough that stretches from Chicken to Anaktuvuk Pass will move to Northway Chandalar Lake to Anaktuvuk Pass by Sat, and then persist into Mon. This will be a focus for isolated convective thunderstorms over the Eastern Interior over the weekend, and also delineate the warmest surface temperatures. The driest and warmest conditions will be northeast of the trough. A vertically stacked 1009 mb low 300 NM west of Point Hope will move to 400 NM northwest of Utqiagvik as a 1013 mb low by 4pm Sat, remain in place through 4pm Sun, and then move to 200 NM west of Utqiagvik as a 1914 mb low by 4pm Mon. This is causing SW winds 15 to 25 mph from the Bering Strait to Point Hope that will spread to the Western Arctic Coast on Sat while decreasing over the Bering Strait. Winds will decrease most areas on Sun. Fog along the Arctic Coast east of Utqiagvik will continue through the weekend, thinning in the afternoon and evening each day. Strong high pressure over the Beaufort Sea will weaken Sun and Mon. Fog along the Arctic Coast east of Utqiagvik will continue through the weekend, thinning in the afternoon and evening each day. Strong high pressure over the Northern Bering Sea and West Coast of AK will persist through Sun and then weaken on Mon. This will cause fog along the West Coast that will continue through the weekend, thinning in the afternoon and evening each day. Fog will thin most areas on Mon. && .DISCUSSION... Models initialize well aloft and show similar solutions through Mon with just very slight differences in short wave speed. The long wave pattern consists of an omega block with the blocking high over Mainland AK. That blocking high will build slightly through Sun and then persist into next week. This will keep most of Northern AK warmer than normal and dry. A vertically stacked low over the Chukchi Sea will move over the Northern Chukchi Sea Sat and Sun, then back over the Southern Chukchi Sea Mon and Tue. A weak short wave trough stretching from Chicken to Atigun Pass will move to Northway to Nenana to Atigun Pass by midnight tonight. This is causing isolated thunderstorms that will move southwest with the trough. Where this trough is intersecting higher moisture conditions it is causing a band of strong thunderstorms that stretches from the White Mountains to Chicken that will spread to Fairbanks to Northway later this afternoon and evening and to the Alaska Range by late evening. The thunderstorms will have strong gusty winds, hail up to one half inch in diameter, frequent lightning and brief heavy rain. All models show 850 mb temperatures of +10 over the Nrn Interior, Interior near the ALCAN Border, and over the Central and Ern Brooks Range cooling to 0C over the Seward Pen and NW AK. That cooler air will spread north over the Chukchi Sea tonight and Sat, while most of Nrn AK will warm 2-4C on Sat, then warm 1-2C on Sun and remain that warm into Mon. Surface temps will rise 5-10F at the surface in most areas on Sat, then rise a few degrees F on Sun and remain warm into Mon. With precipitation, models show similar areas for convective showers. The Eastern Interior is the main area for convection through the weekend. Today expected isolated to scattered showers, and isolated to widely scattered PM thunderstorms, then just isolated PM thunderstorms Sat through Mon. The widely scattered thunderstorms this PM are in a band from the White Mountain to to Chicken and will spread to Fairbanks to Northway later this afternoon and evening and to the Alaska Range by late evening. They will have strong gusty winds, hail up to one half inch in diameter, frequent lightning and brief heavy rain. Thunderstorms today are higher based over NE AK and could produce dry lightning from Eagle to the Yukon River Bridge northeast. Areas of light rain from the Bering Strait to Point Hope will move north over far NW AK tonight, over the Chukchi Sea on Sat, and bring a chance of rain to the Western Arctic Coast of AK on Sun and Mon. At the surface at 18Z, models verify about 8 mb too weak on the low south of Adak but verify well on most other features. Models show fairly similar solutions through Mon. Winds should remain below 15 mph over the Interior through Mon other that thunderstorm gusts. SW winds 15 to 25 mph from the Bering Strait to Point Hope will spread to the Western Arctic Coast on Sat while decreasing over the Bering Strait. For Sun into Mon coastal winds will be 20 mph or less. Coastal Hazard Potential Days 3 and 4...None. && .FIRE WEATHER... Drier and warmer conditions are expected over most of Northern Alaska this weekend into early next week. Conditions will be similar to last weekend but with much less wind. The Eastern Interior is the main area for convection through the weekend. Today expected isolated to scattered showers, and isolated to widely scattered PM thunderstorms, then just isolated PM thunderstorms Sat through Mon. The widely scattered thunderstorms this PM are in a band from the White Mountains to Chicken and will spread to Fairbanks to Northway later this afternoon and evening and to the Alaska Range by late evening. They will have strong gusty winds, hail up to one half inch in diameter, frequent lightning and brief heavy rain. Isolated dry thunderstorms are occuring today from Eagle to the Yukon River Bridge northeast causing Red Flag conditions in that area due to very dry fuel conditions in that area. && .HYDROLOGY... High water from snowmelt has made its way down rivers to the coast on the Central North Slope. The high water is caused by warm temperatures and snow melt in the Brooks Range. It is expected that water levels will fall slowly through the the weekend and into next week. Periods of heavy showers fell along the North Slopes of the Alaska Range, and over the Goodpaster River Basin, and the Upper Charlie and Upper Fortymile River Basins the past few days. Rainfall amounts range from one half to nearly 2 inches, with the heaviest amounts along the Alaska Range to the east of Denali Park. This water is now working its way down rivers. The small rivers have now crested and are beginning to fall. Larger rivers such as the Tanana, the Delta, the Nabesna and the Chisana Rivers will rise over the next several days and people along those large rivers should be alert to rising water. No flooding is expected. && .AFG WATCHES/WARNINGS/ADVISORIES... AK...Red Flag Warning for AKZ933-935. PK...Brisk Wind Advisory for PKZ807. Small Craft Advisory for PKZ810. Small Craft Advisory for PKZ811-857. Small Craft Advisory for PKZ812. Brisk Wind Advisory for PKZ814-815-861. Small Craft Advisory for PKZ856. Small Craft Advisory for PKZ858. Brisk Wind Advisory for PKZ860. && $$ JB