Marine Weather and Tide Forecast for Emmonak, AK

SYNOPSIS
An arctic trough is rapidly moving west to east across the North Slope this morning bringing a cold front across Northern Alaska.
This cold front is bringing some light snow and freezing drizzle to the Tanana Valley, but by this afternoon conditions should dry out.
Across Northern Alaska temperatures will be begin to drop as cooler arctic air makes a return to the region. For most Sunday will be the coolest day ahead of an approaching weak low pressure in the Southern Bering. This low will help to facilitate rapid development of another low that will enter the Gulf of Alaska Monday night. This low is expected to bring heavy snowfall to the Eastern Alaska Range and moderate snowfall to parts of the Central and Eastern Interior.

SHORT TERM /THROUGH MONDAY NIGHT/

The short term period begins with the low pressure system in the Gulf of Alaska tracking east and decaying through Saturday morning. The system previously sent a warm front throughout Alaska, and some of the warmer air, along with its moisture, will remain in the Interior as it dissipates Saturday morning.
Following this storm a cold front is moving east through the Interior. This front is the driving factor for the majority of the weather expected through Sunday.

As the cold front continues to track east, it will to bring another round of snowfall throughout the Interior, but recent model guidance is still struggling with the exact amount of snowfall that this front will bring. Ahead of the front is the remnant moisture from the decaying gulf storm, and typically with this moisture present, most of the mid and lower levels of the atmosphere would be saturated. This would allow the approaching cold front to create the frontogenetic lift needed to produce snowfall throughout the Interior. As the cold front approaches it will run into the warmer air from the previous warm front. While on a synoptic scale most of the warmer air is forced out of our region, when focusing on a more local scale some of the air is still lofted upward into the atmosphere.
According to the latest sounding observation, the DGZ (Dendritic Growth Zone) is currently saturated between -12C to -15C, and starts around 8,300ft. The cold front is directly over Fairbanks, and is well defined with backing winds of about 40 degrees between 1000ft to 3000ft. Current surface temperatures are below freezing, and allow for minor snowfall accumulations.
As temperatures rise to above freezing throughout the day, these accumulations are expected to melt. Once the cold front moves through the Interior, the expectation is for drier conditions to persist, resulting in snowfall rates gradually decreasing through Saturday evening.

Outside of the Interior, there are possible snowfall accumulations in the North Slope. With temperatures ranging on average just below freezing, accumulation is possible throughout the weekend of upwards of 3 inches. During this time a pressure gradient between an arctic low and siberian high will form with the Chuckchi Sea, exposing the Northeast Arctic Coastline to a round of gusty winds. These southeasterly winds will pick up Sunday morning around the same time snowfall is expected, which could lead to brief periods of blowing snow and patchy fog.

In the wake of the cold front a more stable environment is expected, with potential for pockets of scattered to clear sky conditons. Cooler temperatures are expected, with most of the state having highs that will be at or just below freezing, and lows in the mid teens to 20s through the weekend. Lower elevations have the possibility for cooler conditions to persist as the arctic air becomes entrenched in the valleys.

On Monday there is potential for another low to begin to circulate with the Bering Sea, creating a pressure gradient with a weak ridge over eastern Alaska and some gusty winds along the West Coast and Alaska Range passes. This storm will be the driver of the weather in the extended period. This will be discussed more in the extended forecast.


LONG TERM /TUESDAY THROUGH FRIDAY NIGHT/

Looking ahead towards the middle of next week, a shortwave trough will have intensified in the Northern Gulf and will make its way towards Southcentral Alaska. Models are in good agreement on the track and the potential strength of this system. While this system is not anticipated to be a wind threat for Northern Alaska it could be the first potential heavy snowfall event for parts of the Central and Eastern Interior. Models are in fairly good agreement that the Eastern Alaska Range will see periods of heavy snowfall Monday to Wednesday. While it is early season gusty northerly winds and heavy snowfall could create blizzard conditions on the southside of Isabell Pass.

Where models begin to diverge is how far into the Interior the warm front makes it. Cold arctic air will remain entrenched into the Interior valleys from a previous cold front which would make it difficult for a weak warm front to move deeper into the Interior.
There is very little model agreement on where this front will inevitably stall. As of now the corridor of highest snowfall will be from McGrath to Fort Yukon. While exact amounts are uncertain for this corridor, all of the ingredients for moderate snowfall are there.

After this storm begins to weaken a ridge of high pressure is expected to develop over mainland Alaska Thursday and Friday.
Southerly chinook flow will bring slightly warmer temperatures across the Interior, but this high pressure is expected to be short lived as another low is expected to enter the Bering Sea by the end of the work week. There is very little model agreement at this time regarding the strength and track of this system, so it will need to continued to be monitored as we move through the work week.

Coastal Hazard Potential...
None.

AFG WATCHES/WARNINGS/ADVISORIES
AK...Wind Advisory from 4 AM Monday to 4 AM AKDT Tuesday for AKZ849.
Winter Storm Watch from Monday afternoon through late Wednesday night for AKZ849-850.
MARINE...Small Craft Advisory from 4 AM to 6 AM AKDT Sunday for PKZ801- 806.
Small Craft Advisory until 7 AM AKDT this morning for PKZ808- 855.
Small Craft Advisory until 10 AM AKDT this morning for PKZ809.
Small Craft Advisory from 10 PM this evening to 6 AM AKDT Sunday for PKZ812.
Small Craft Advisory from 1 PM this afternoon to 4 AM AKDT Sunday for PKZ814.
Small Craft Advisory from 7 PM this evening to 6 AM AKDT Sunday for PKZ815.
Small Craft Advisory from 1 AM to 6 AM AKDT Sunday for PKZ850.
Small Craft Advisory from 1 AM to 4 AM AKDT Sunday for PKZ858- 861.
Small Craft Advisory from 4 PM this afternoon to 4 AM AKDT Sunday for PKZ860.