Area Forecast Discussion
Issued by NWS Fairbanks, AK
Issued by NWS Fairbanks, AK
834 FXAK69 PAFG 091025 AAA AFDAFG Northern Alaska Forecast Discussion...UPDATED National Weather Service Fairbanks AK 225 AM AKDT Thu May 9 2024 SYNOPSIS... Generally unsettled weather conditions persist throughout the next several days with showery conditions remaining. Strong southerly gap flow winds in the Alaska Range diminish this morning with a wind advisory out until 10 am. A flood watch remains in effect for the Yukon River at circle. DISCUSSION... Model Analysis... Aloft, at 500 mb, a 515 dam (decameter) low near the Alaska Peninsula will weaken as it moves east over Kodiak Island and becomes an open wave near Cordova by Friday morning before lifting north across the Interior and into Canada Friday evening through Saturday. This will push at the ridging allowing temperatures to cool slightly in the Interior today and Friday. Models initialized 1 to 2 dam too low on this ridge which will limit the impact of this low as it moves through. Models are in relatively good agreement through Friday with differences increasing Saturday, although general pattern of ridging along the Alcan border and troughing along the West Coast remains. Models indicate that a roughly 527 dam low will enter the Gulf of Alaska Saturday night and weaken through Sunday possibly pushing the ridging east again early next week. At the surface a low follows the progression of that upper level low as it fills in. A 1000 mb low in the Northwest territories will move fill in and move east today. Troughing across most of northern Alaska that was stretched between these two lows will weaken and fill in as these surface lows weaken. A 980 low in the Bering Sea this morning will move east along the Aleutians, slowly weakening as it meanders into the Gulf of Alaska by Saturday afternoon. This low is associated with the 527 dam low mentioned previously and sees similar model differences in its exact strength and position with models averaging about 999mb by Saturday afternoon. Weak surface lows and small disturbances will persist across Northern Alaska as that trough weakens and is then reinforced by the second low. North Slope and Brooks Range... A round of snow this morning for the western North Slope as a surface low tracks west across the North Slope. This same low was responsible for overnight snowfall along the central and eastern Arctic Coast and is expected to move off shore tonight. North winds 15 to 20 mph are expected west of this low with no blowing or drifting snow concerns. Winds elsewhere are expected to remain under 15 mph. 1 to 2 inches of snowfall is expected along the Western North Slope this morning with this system. Conditions remain calm and dry after the passage of this low through the weekend. Areas of fog and stratus are expected to persist. Highs in the 20s to low 30s. West Coast and Western Interior... Some northern winds in the 15 to 25 mph range along coastal areas from Point Hope to Kivalina and south through the Bering Strait will strengthen slightly today as the low along the North Slope moves westward further squeezing the pressure gradient through this area, but then weaken as the low fills in. Winds under 15 mph expected elsewhere. Small disturbances and the general troughing will provide support for continued showers through Friday with some isolated to scattered on this weekend. Highs in the 40s to low 50s in the Western Interior and from 25 to 40 along the West Coast. Central and Eastern Interior... Showery activity persists as disturbances aloft continue to propagate. A mix of rain, snow, and rain-snow mix is expected with most low lying areas getting rain. Slight chance of thunderstorms from Huslia to the Yukon Flats this afternoon along with showers. Strong southerly gap flow in the eastern Alaska Range will weaken today. Winds elsewhere will generally be less than 15 mph with winds being slightly higher and gusty near showers. Highs in the 50s to low 60s becoming slightly warmer Saturday as ridging builds back up again. Extended Forecast Days 4-7... Model Guidance continues to indicate persistent broad upper level troughing over most of the forecast area throughout the extended forecast period. Periodic intrusions of ridging from Canada into the eastern Interior are also suggested. This pattern will continue to support scattered showers across much of northern Alaska. Coastal Hazard Potential Days 3 and 4...None. FIRE WEATHER... Strong southerly gap flow winds in the eastern Alaska Range will weaken this morning. These winds have helped dry out the area north of Isabel Pass to Delta Junction. Winds will have diminished significantly by the time of peak heating this afternoon so Red Flag conditions are not anticipated. However near red flag conditions are possible from Delta Junction to Donnelly Dome early this afternoon. Minimum relative humidity values of 20 to 25 percent are expected in this area this afternoon with values in the 25 to 30 percent range along the rest of the Tanana Valley and near Eagle with 30 percent and higher expected elsewhere in the Interior. High temperatures in the 50s to near 60 through Friday. Scattered to Numerous showers expected today throughout the Interior as a disturbance moves through today. SLight chance of thunderstorms this afternoon north of the White Mountains from Huslia east to the Yukon Flats. Isolated to scattered showers will remain throughout the weekend as more disturbances move through the area. HYDROLOGY... The breakup front on the Yukon river is approaching Circle and expected to reach Circle in the near future. As of 7 pm Wednesday, an ice jam was in place 12 miles upriver from Circle with some overbank flooding of low areas with no water over higher banks. Downstream of circle, small sloughs and streams are clearing of ice, but the main channel of the Yukon still has ice in-place. The Tanana and Upper Kuskokwim River are mostly open. Rivers north of the Yukon River have mostly intact ice. && .AFG WATCHES/WARNINGS/ADVISORIES... AK...Wind Advisory for AKZ849. Flood Watch for AKZ833. PK...Small Craft Advisory for PKZ806. Heavy Freezing Spray Warning for PKZ806. && $$