textproduct: Fairbanks

SYNOPSIS

Cold and generally benign conditions exist across the majority of Interior Alaska today with the exception of a few locations along the coasts observing blowing snow. Blizzard Warnings and Winter Weather Advisories remain in effect through Wednesday for the northeast Arctic Coast as strong west-southwest winds have resulted in blowing snow and significantly reduced visibility at times. Strong northwest winds through the Chukchi Sea and Kotzebue Sound will persist for at least another 24 hours with blowing snow also reducing visibility for coastal locations. The Interior remains dry and very cold for Mid March with double digit sub zero lows expected each day this week and possibly into the weekend. A slight warming trend arrives for the West Coast by midweek as a few weak systems traverse the Bering from the northwest increasing clouds and chances for light snow.

KEY WEATHER MESSAGES

Central and Eastern Interior...

- Well below normal temperatures this week with daily morning lows reaching the 20s to 40s...coldest spots being Interior valleys.

- Expect large diurnal temperature fluctuations due to the strong March sun with afternoon highs reaching the single digits above and below zero.

West Coast and Western Interior...

- Gusty northwest winds resulting in blowing snow and reduced visibility continue for portions of the northern Seward Peninsula and Kotzebue sound through the next 24 hours.

- Below normal temperatures the next few days with double digit sub zero lows, followed by a warm up to the teens above the latter half of the week into the weekend

- Light snow accumulations possible Wednesday and Thursday for all of the West Coast and far western Interior

North Slope and Brooks Range...

- Blizzard to near blizzard conditions at times due to blowing snow and low visibility for the northeast Arctic Coast through Wednesday

- At or below normal temperatures persist through the period with double digit sub zero lows each day

FORECAST ANALYSIS AND DISCUSSION

Cold and relatively dry conditions persist for Northern Alaska as deep troughing over the state and Northern Canada and northerly flow keep the storm track away from the region and an arctic airmass in place near the surface. While the majority of the interior remains dry, cold, and quiet through the weekend, a few areas of more active weather exist for the Arctic Coast and West Coast over the next few days.

For the Arctic Coast and Brooks Range, the region remains under the influence of a complex upper low over the Canadian Archipelago with numerous shortwaves rotating about it and into the state. RAOB soundings from BRW show low to mid level saturation below an inversion around 5,000 ft agl and based on satellite imagery and observations, this sounding is likely representative for the majority of the North Slope. Persistent northerly flow and waves of energy should keep low to mid levels clouds and snow showers around for the next several days. A classic barrier jet has set up for the Northeast Arctic Coast from Point Thomson to Barter Island resulting in gusty WSW winds, blowing snow and very low visibility at times for this region. The surface low in the high arctic and its associated barrier jet remain in place through early Wednesday before ridging builds in from the west. For the next 24 to 36 hours, expect similar conditions to persist for the Arctic before a pattern change arrives midweek.

Across the west, strong ridging both at the surface and aloft are in place over the Bering keeping strong northerly flow through the Chukchi sea and Bering Strait. Persistence is key when it comes to the forecast for the next 24 to 36 hours as the synoptic scale systems remain in place for now before more active weather arrives on Wednesday. Northwesterly winds have resulted in blowing snow and reduced visibility for portions of the northern Seward Peninsula and toward Kotzebue, while the rest of the west remains very cold and dry. Strong northwesterly flow is keeping the deep arctic airmass in place and highs near or below zero with double digit sub zero lows.

Outside of any active weather along the Coasts, the interior stays very cold for this time of year as the aforementioned arctic airmass remains in place and surface high pressure moves in overhead. While conditions will be generally clear for the interior, forecast soundings do show enough low level moisture in place to support ice fog developing the next few nights, especially as many areas make a run for -30F to -45F for overnight low. The strong march sun angle should result in any fog dissipating during the afternoon hours. Confidence on where and when ice fog develops is low; however the upcoming pattern the next several nights supports its development.

EXTENDED FORECAST DAYS 4-7

Well below normal temperatures continue into the extended period for much of Alaska. While a few systems bring light precipitation to the West Coast, the interior remains cold and dry for the foreseeable future. Upper troughing over the state and strong ridging over the Bering have been keeping most of the storm track to the south, with no big systems to kick out the arctic airmass in place. Longer range guidance shows well below normal 850mb temperatures in the -teens to -30C range through mid to late month, supporting lows in the -20F to -40F range and highs struggling to reach zero. Interior valleys will be the coldest locations in this type of weather pattern.

Focus shifts to Wednesday through Friday as weaknesses in the Bering Sea ridge allow for shortwaves to ride up and over it and into the West Coast. Weak ridging shifts eastward setting up across the North Slope and Western Interior as numerous elongated shortwaves move in from Siberia and down into the Bering. With most of the energy staying over the Bering, then sliding southward, expect the best chance for any snowfall from these systems to remain closer to the coast. The YK Delta along the coast, northward to Nome and to the NW Arctic Coast and points west likely will have several days of light snow Wednesday through Friday with minor accumulations expected. A brief period of relatively warmer conditions likely for the west coast during this period as cloud cover, snow, and influence from the Bering Ridge weaken the low level inversion and moderate the airmass slightly allowing for temperatures in the single digits and teens above zero.

For the North Slope and Arctic Coast, a subtle pattern change arrives mid to late week. As shortwaves cut through the ridge over the Bering and Siberia, a piece of the ridge breaks off and shifts east extending from the Arctic Coast through the western interior Wednesday, while surface high pressure sets up over the North Slope. High pressure should shut off the barrier jet along the coast, resulting in much calmer surface winds Wednesday through the end of the week, especially along the coast where a long stretch of blowing snow and low visibility had been occuring. Subsidence under the high in addition to shortwaves now moving in from the west/northwest should keep clouds and moisture trapped in the lower levels for the latter half of the week. Relatively benign weather only lasts a few days for the Arctic as additional systems move in from the north by the weekend increasing winds and chances for snow and blowing snow once again for at least the Northeast and Northwest Arctic Coasts.

Coastal Hazard Potential Days 3 and 4...None

AFG WATCHES/WARNINGS/ADVISORIES

AK...Winter Weather Advisory for AKZ818. Blizzard Warning for AKZ804-805-808. PK...Brisk Wind Advisory for PKZ801-850. Brisk Wind Advisory for PKZ802. Brisk Wind Advisory for PKZ803. Brisk Wind Advisory for PKZ805>807-852>854. Brisk Wind Advisory for PKZ808-809-814-815-855-856-860-861. Brisk Wind Advisory for PKZ810. Brisk Wind Advisory for PKZ811.