Alaska, 2012

Heavy Snow in Alaska, January 9 to 11, 2012

January 9 to 11, 2012 · NWS AFG · 2 events in 2 counties and zones

An inverted surface trough extended north into the Lower Koyukuk and Middle Yukon Valley from a 978 mb low along the Alaska Peninsula at 0300AKST on the morning of the 10th. The low moved north and weakened to 994 mb in the western interior by 0300AKST on the 11th.

The toll

Deaths
0
Injuries
0
Property damage
None recorded
Crop damage
None recorded
Events
2

Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.

What happened

The episode as NWS AFG wrote it up.

An inverted surface trough extended north into the Lower Koyukuk and Middle Yukon Valley from a 978 mb low along the Alaska Peninsula at 0300AKST on the morning of the 10th. The low moved north and weakened to 994 mb in the western interior by 0300AKST on the 11th. Heavy snowfall was observed in parts of the lower and middle Yukon Valleys.

Zone 215: Approximately 12 inches of snow was observed at the Anvik Post Office. The snow began during the evening hours on the 9th and continued until the evening hours on the 10th.

Zone 216: Heavy snowfall was observed near Ruby. The cooperative observer 14 miles northeast of Ruby observed a total of 12.8 inches of snow from approximately 2000AKST on the 9th through 0800AKST on the 11th.

What forecasters said that day

The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Fairbanks, AK wrote its last area forecast discussion before the first event at Jan 9, 3:06 PM AKST, 2 hours 54 minutes earlier.

Area forecast discussion, Jan 9, 3:06 PM AKST, 2 hours 54 minutes before
NORTHERN ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FAIRBANKS AK
306 PM AKST MON JAN 9 2012

.DISCUSSION...
MODELS IN DECENT AGREEMENT THROUGH 60 HOURS. UPPER LEVEL TROUGH
OVER MOST OF NORTHERN ALASKA WILL GIVE WAY TO A FAST MOVING RIDGE
BEING AMPLIFIED BY A LOW IN THE NORTH PACIFIC MOVING EAST TOWARD
THE GULF OF ALASKA. THEN BY TUE AFTERNOON THE UPPER LEVEL TROUGH
OVER THE WEST COAST WILL DEEPEN SOUTHWARD AND BEGIN MOVING
EASTWARD WITH THE AXIS OF THE TROUGH MOVING TO BE FROM NEAR THE
NORTH POLE SOUTHWARD TO THE GULF OF ALASKA BY THU AFTERNOON. THE
COLDEST AIR WILL BE WITHIN THE TROUGH.

A RIDGE OF HIGH PRESSURE WILL BEGIN TO BUILD IN THE NORTH PACIFIC
TO THE BERING STRAIT AND THEN NORTHWARD TO SIBERIA BY THU
AFTERNOON AND EVENING. THE ECMWF SUGGESTS THAT THE THE RIDGE WILL
THEN DEVELOP INTO AN OMEGA BLOCK IN THE BERING SEA.
HOWEVER...OTHER MODELS SUGGEST THE OPPOSITE WILL OCCUR WITH A
TROUGH OF LOW HEIGHTS SPREADING EASTWARD FROM NORTHERN CANADA TO
THE BERING SEA THROUGH THE WEEKEND WHICH WILL KEEP THE COLD AIR
FIRMLY IN PLACE OVER NORTHERN ALASKA.

THE NEXT SURFACE LOW MOVING NORTHWARD TO NEAR DILLINGHAM BY TUE
AFTERNOON WILL SPREAD A BAND OF RELATIVELY HEAVY SNOWFALL THROUGH
THE Y-K DELTA WHILE THE BRUNT OF THE PRECIPITATION FINDS ITS WAY
TO THE SNOW MAGNET AREA OF THE NORTH COAST OF THE GULF OF ALASKA.
THIS SHOULD SPREAD FROM 8 TO 10 INCHES OF OROGRAPHICALLY ENHANCED
SNOWFALL OVER MUCH OF THE AREA OF ZONES 215 AND 216 THROUGH TUE NIGHT.

WINDS THROUGH THE ALASKA RANGE PASSES WILL CONTINUE TO INCREASE
THROUGH TUE NIGHT AND CONTINUE THROUGH TUE. THIS WILL CAUSE AREAS
OF BLOWING SNOW THROUGH THE ALASKA RANGE PASSES. INITIALLY WIND
CHILLS WILL BE FLIRTING WITH ADVISORY LEVEL CRITERIA BUT
TEMPERATURES SHOULD MODERATE SIGNIFICANTLY ENOUGH TO DO AWAY WITH
THAT BY LATER IN THE EVENING IN ZONE 225.

FOR THE FUEL DELIVERY THAT IS DESTINED FOR NOME BY THE CREWS OF
THE RENDA AND THE HEALY...EXPECT NORTHERLY WINDS OVER THE BERING
STRAIT COAST AND THE NORTHERN BERING SEA THAT WILL CONTINUE TO
INCREASE BEGINNING LATE TONIGHT. NORTH WINDS WILL INCREASE TO 20
TO 30 KT BY TUE MORNING AND CONTINUE THROUGH TUE. COLD AIR WILL
REMAIN LOCKED IN OVER THE AREA AND WIND CHILLS WILL BE APPROACHING
50 BELOW OVER MUCH OF THE AREA. WINDS WILL STAY NORTHERLY BUT
TURNING SLIGHTLY NORTHWESTWARD ON WED AND DIMINISHING SLIGHTLY. AT
THIS POINT IT DOES NOT APPEAR THAT SNOW WILL BE A FACTOR...THE
SNOW WILL REMAIN EAST OF THE AREA THAT WILL BE THE CORRIDOR TO
NOME.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY FOR AKZ227.

WINTER STORM WARNING FOR AKZ215-AKZ216.

WIND CHILL ADVISORY FOR AKZ201-AKZ202-AKZ203-AKZ206-AKZ207-
AKZ213.

WIND CHILL WARNING FOR AKZ209-AKZ217.

WINTER WEATHER ADVISORY FOR AKZ220-AKZ225-AKZ226.

BRISK WIND ADVISORY FOR PKZ225-PKZ235.
&&

CF JAN 12

Event by event

2 heavy snow. Local standard time, as filed.

Heavy Snow, Lower Yukon Valley

When
January 9, 6:00 PM AKST to January 10, 6:00 PM AKST
Where
Lower Yukon Valley forecast zone
Reported by
Post Office

Heavy Snow, Lower Koyukuk Middle Ykn Vlys

When
January 9, 8:00 PM AKST to January 11, 9:00 AM AKST
Where
Lower Koyukuk Middle Ykn Vlys forecast zone
Reported by
COOP Observer

What these are

Heavy Snow
Snowfall reaching the local warning threshold without the other hazards of a winter storm.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

More

Every storm in Alaska in 2012Every state in 2012This day in weather historyWarnings in Alaska, January 2012

Sources

NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 353664, 353665.