Area Forecast Discussion
Issued by NWS Fairbanks, AK
Issued by NWS Fairbanks, AK
930 FXAK69 PAFG 160932 AFDAFG Northern Alaska Forecast Discussion National Weather Service Fairbanks AK 132 AM AKDT Sun Jun 16 2024 .SYNOPSIS... A hot day is expected for the Interior today with widespread 80 degree reading as a ridge aloft remains parked overhead. This will limit precip chances and it will largely be cloud free except over higher elevation terrain where there will be isolated thunderstorms once again. Showers and isolated thunderstorms will be more prevalent over the Brooks Range. Warmer temps continue into Monday with chances for thunderstorms increasing Tuesday. && .DISCUSSION... Upper Levels and Analysis... There is a dominant 570 dam upper ridge over the entire S Mainland. There is a meandering cutoff arctic low over the Chukchi Sea, with heights around 538 dam. There is a small shortwave trough over the Prince William Sound area. A surface high around 1026 mb is situated over Saint Lawrence Island with another 1022 high over the Beaufort Sea near the coast. There is a 1014 mb low underneath the aforementioned arctic low, and a weak thermal trough over the E Interior. Model Discussion... Models are locked into the synoptic scale pattern with the main discrepancies revolving around challenges models normally have with things like thunderstorms. We favor a NAM hi-res blend for winds, with a blend to all models for precip chances, temps, and thunderstorms. Central and Eastern Interior... Warmer today than yesterday, with widespread low to mid 80s over the Interior. It`ll be mostly sunny with only isolated thunderstorm chances over the higher mountain terrain, and even then it will be fairly spotty. Monday, another warm day with more 80s and upper 70s, with a better chance for thunderstorms over the Alaska Range, and also farther north over the slopes of the Brooks Range to the Yukon Flats and White Mtns. Tuesday, still warm, but a couple degrees cooler with a better chance for thunderstorms everywhere, although the focus will be over the Central Interior to the Upper Koyukuk, the White Mtns, and into the Yukon Flats since the steering flow will be southerly and the most instability will be in those places. West Coast and Western Interior... High pressure shifts west from Saint Lawrence Island and this will increase north winds over the YK Delta, but it will mostly be the same weather today except a couple degrees warmer perhaps, with general west flow everywhere else. Monday remains warmer, with a much better chance for afternoon isolated thunderstorms and heavy showers over the Kuskokwim Valley and into the Kuskokwim Mountains. Meanwhile, the arctic low will be diving south over the NW Arctic, bringing chances for rain showers from Point Hope down the Bering Strait, by Tuesday. Widespread thunderstorm chances develop Wed over the Interior. Some storms may be strong over the northern half of the Interior, from Galena northward. North Slope and Brooks Range... Showers with isolated thunderstorms are expanding in coverage today over the Central and E Brooks Range as a disturbance passes over. Meanwhile, a meandering arctic low will continue to bring southwest winds to the NW Arctic with increasing chances for showers reaching Utqiagvik and then to Umiat by Monday. Showers with isolated thunderstorms continue over the E and Central Brooks Range through Tuesday as westerly flow over that area continues. The E Arctic has cleared, but stratus is lurking offshore, but it may not come back until tonight, so a sunnier day is expected again today. Extended Forecast Days 4-7... The general consensus among the global suite of numerical weather models and their ensembles, as well as the ECMWF AI Machine Learning model, is that weak Interior ridging aloft will be in place Wednesday, with an arctic low shifting west to Siberia, and another Gulf of AK low developing. This is a pretty typical midsummer pattern with seasonal temps and chances for thunderstorms daily, along with heavier rainfalls over the SE Interior to AK Range. It`ll otherwise be cooler over the West Coast with shower chances largely ending by the end of week. Coastal Hazard Potential Days 3 and 4...None. && .FIRE WEATHER... Today is even hotter and still generally dry, with only some very spotty isolated wet thunderstorms over the higher elevation terrain of the Interior, such as the Alaska Range and White Mtns as well as some of the higher hills near Fairbanks. Temps will reach the mid 80s over the Yukon Flats with lower 80s elsewhere, with min RHs in the 20s again, and some upper teens over the Yukon Flats. Monday, instability increases along a thermal trough over the Kuskokwim Valley to Kuskokwim Mtns, with the possibility of scattered wet thunderstorms, with isolated wet thunderstorms across the remainder of the Interior including higher based storms over the Yukon Flats. Temps are a couple degrees cooler, but still above seasonal norms. Tuesday, more widely scattered thunderstorms over a broad footprint across the Interior, but uncertainty is higher, as the timing of a wave moving north is hard to predict with certainty right now. However, these storms will be quite wet, with wetting rains over the Central Interior to Upper Koyukuk. More isolated wet thunder will be over the E Interior, with southerly steering winds. The ridge is weakening is temps are a few degrees cooler Tue. && .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 either fall slowly or remain steady as increased warming over the Brooks Range may allow for additional snowmelt. The Colville is running near bankfull at Umiat and will likely remain so for a while. && .AFG WATCHES/WARNINGS/ADVISORIES... AK...None. PK...Small Craft Advisory for PKZ811. Small Craft Advisory for PKZ857. && $$ Ahsenmacher