textproduct: Anchorage

Update

Key Messages:

Winter Weather Advisory for Broad Pass through Sunday Morning for 4 to 12 inches of snow. Steady snow this morning may mix with rain and taper off for a time this afternoon before a second round of snow this evening through Sunday morning. Snow amounts will be highly dependent on temperatures with daytime highs in the lower to mid 30s.

PREV DISCUSSION

/issued 420 AM AKDT Sat Oct 10 2026/

SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 through 3: Today through Monday night)...

The forecast is on track this morning as a strong occluded front is pushing east from the western Gulf. South to southwesterly flow aloft is driving ample moisture from the North Pacific out ahead of the front and over Southcentral Alaska. The heaviest precipitation is falling along the coast and across areas favored by upslope flow, such as northern and eastern portions of the Susitna Valley from Hatcher Pass to Broad Pass. A strong pressure gradient between a surface ridge over the eastern Gulf and deep low pressure in the Bering has also resulted in gusty winds for many locations and has also allowed for the development of strong southeasterly gap winds through Turnagain Arm and the Knik River Valley, where gusts have peaked around 40 mph overnight.

Light rain across the Anchorage Bowl and western Kenai overnight has tapered off a bit this morning as weak southeasterly flow aloft and exiting shortwave have allowed for some downsloping. While the southeasterly flow will continue to increase through the morning and early afternoon hours, upper-level waves (i.e. advecting vorticity lobes) will allow for periods of rain throughout the day.

Snow levels today will rise from around 2,000 ft near the Alaska Range and 2,800 ft farther south to around 2,600 ft and 3,200 ft, respectively, through the day. This will allow snow falling through mountain passes this morning to at least mix with rain for a time this afternoon before snow levels fall and precipitation changes back to snow tonight through Sunday morning.

There remains high confidence in light accumulations expected at the passes (2-4" lower Broad Pass, 3-6" top of Broad Pass, 4-7" Thompson Pass). Confidence is also high (80-90 percent) for higher elevations of Hatcher Pass (> 3,000 ft)to see 6-12 inches of snow with this system (with totals closer to 2 feet above 4,000 ft). For lower elevations, temperatures will continue to warm throughout the weekend as this system moves through.

Regarding precipitation amounts, the heaviest and most persistent precipitation is expected to be along the northern Gulf Coast (widespread 2-3 inches through Sunday afternoon with some locally higher amounts possible) and the western Alaska Range to the northern Susitna Valley (1-3 inches through Sunday afternoon with some locally higher amounts possible). Downsloping winds will result in lower total precipitation amounts for the western Kenai, Anchorage, lower Mat-Su Valleys, and the Copper River Basin.

Regarding winds, high confidence of gusts up to 55 mph through Turnagain Arm and the Anchorage Hillside and up to 45 mph and 40 mph, respectively, for Knik River and Copper River Valleys. Southerly small-craft force winds persist through the Gulf on Saturday, with some gales possible in the southern portion of Cook Inlet.

By late Saturday, models show a shortwave driving northward along the front which will spin up a new surface low NE of Kodiak as the upper-level wave becomes more negatively tilted. Again, there is good model agreement that this new feature and its front then drive toward the northern Gulf for late Saturday with the development of a coastal ridge out ahead of the front. There is high confidence (80-90 percent) that this solution will further enhance SE gap winds through typical locations; however, with the low south of the Kenai Peninsula, a down inlet flow will set up with moderate confidence (50-60 percent) that the Turnagain Arm jet bends south and away from Anchorage by Saturday evening.

As the low and its associated upper-level trough continues to lift north Saturday night into Sunday, the barrier jet off the northern Gulf Coast accelerates to gale-force. Some easterly gale-force winds likely make it into Price William Sound Saturday night into early Sunday morning. Winds quickly decrease for across Southcentral once the front moves through, with the Turnagain Arm wind decreasing Saturday night and the barrier jet decreasing Sunday morning. With decreasing winds, the effects of downsloping also decrease for the western Chugach and Kenai Peninsula. This will allow precipitation to fill in across the Cook Inlet and Anchorage Bowl as cross-barrier flow diminishes and gusty southwesterly flow (especially aloft) redevelops. Rain may also make it over the Chugach and into the Copper river Basin Sunday morning as the low moves into the coast and quickly dissipates.

Troughing continues over Southcentral through Monday. Clouds and rain showers will likely (60 to 70 percent) linger through Monday across coastal Southcentral, the Cook Inlet through Mat-Su Valleys, and along the Alaska Range, with heaviest rain along the northern Gulf Coast and snow showers over the coastal mountains and Hatcher Pass. High confidence (>90%) of additional snow accumulations for the passes late Sunday into Monday.

-TM/PA

SHORT TERM FORECAST SOUTHWEST ALASKA/BERING SEA/ALEUTIANS (Days 1 through 3: Saturday through Monday)...

The forecast remains very much on track as the west quiets down for now. A large and occluded Bering low continues to spin west of Saint Matthew Island this morning. This low will progressively fill and weaken as it generally moves northeastward towards the Norton Sound through the end of the short term forecast period. Currently, the 500 mb flow is characterized by broad, neutrally tilted troughing over the Bering, Aleutians, and North Pacific with several weak shortwaves rounding the base of the trough. This will coincide with increased shower potential as these waves pass overhead. The first shortwave is now located over the Central Aleutians, closely followed by a second wave diving a bit farther south over the North Pacific. Both of these features are progged to move northeastward towards the Bristol Bay and Alaska Peninsula areas by this evening, where rain chances have been increased for this morning's forecast package. There is some spread in the models on the exact track of the second upper wave, and some of the guidance has it sliding south of the Alaska Peninsula and more on track to move over Kodiak Island by Sunday morning.

Weakening cyclonic flow aloft Sunday afternoon (depicted as 500 mb geo-potential height rises as the upper level low continues to lose steam as it moves over the Norton Sound) will result in overall decreases in chances of precipitation, but showers will remain moving west to east across the Bering/Aleutians and into Southwest Alaska. By Sunday afternoon, yet another wave embedded within the mean 500 mb flow will drive over or just south of the Aleutian Chain. A much more robust shortwave nears the Western Aleutians late Monday as troughing breaks down across/over the region. Have introduced small craft winds for the Western Aleutians starting late Monday through Tuesday morning. The signal in the models is that this wave amplifies, but digs well south thereafter over the North Pacific. Southwest Alaska slowly trends cooler through the end of the short term, with overnight lows dropping to near freezing Tuesday morning area wide.

-AM

LONG TERM FORECAST (Days 4 through 7)...

Forecast uncertainty in the long range remains high with models struggling to resolve the eventual progression of the remnants of Tropical Storm Nolo. Models do agree that broad troughing over the Bering early next week will become more organized and shift from the Alaska Peninsula into the Gulf of Alaska through the latter half of next week. Nolo is expected to be picked up by this trough in some form or fashion, potentially phasing or being absorbed by additional wave energy lifting across the North Pacific. Deterministic guidance takes brings a strong low into the Alaska Peninsula or western Gulf by midweek. Regardless of the various model differences, strong winds (including gales to even storm force winds) are likely next week with rain chances also increasing significantly from the Alaska Peninsula into much of the Gulf of Alaska and Gulf coast. The GFS remains the strongest solution at this time, bringing gales and storm force southeasterly winds into the Alaska Peninsula and Kodiak Island by late Wednesday, with equally northerly winds on the backside of the low spreading into the Eastern Aleutians. Of note, the GFS brings an even stronger low into the Gulf by Thursday with a strong barrier jet setting up along the Gulf coast into Friday.

BL

AVIATION...

PANC... Confidence is high that southeasterly winds will gust up to 30 to 35 kt through early afternoon. Confidence is lower regarding when winds will begin to diminish; model solutions range from as early as 00Z to as late as 06Z. The TAF leans towards the majority consensus among the models, and with gusty winds lingering through about 06Z. Southeasterly winds aloft will remain strong, however, so there will likely be a period of LLWS when surface winds weaken.

Otherwise, vicinity showers (30 to 50 percent chance of showers moving over the terminal) will become more frequent (60 to 80 percent chance) beginning around 03Z. Accordingly, ceilings and visibility will likely drop to MVFR by around 06Z to 09Z.