Area Forecast Discussion
Issued by NWS Fairbanks, AK

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27
000
FXAK69 PAFG 251536
AFDAFG

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
636 AM AKST Sat Feb 25 2017

.DISCUSSION...
Significant winter storm, the third in a series of snow storms
this week is beginning to impact northern Alaska with most areas
north of the Alaska Range under a winter storm warning or winter
weather advisory. Computer models continue in good agreement in
the short range with only minor adjustments needed to snowfall
timing and amounts. The forecast package today incorporates a
large continuity element with only minor adjustments with latest
guidance. The 00z model suite initialized well against the 00z
surface analysis and verified well against the 06z surface
analysis. Model spread remains minimal both from run to run and
between model families through the middle of next week.

Aloft at 500 HPA, a shortwave ridge over the west coast of Alaska
races east today to be over the Canadian border this evening as
an upper level low currently over easter Siberia moves northeast
to be over the Gulf of Anadyr this evening and over the southern
Chukchi Sea Sunday morning. This produces deep zonal flow over
northern Alaska. Abundant moisture is entrained along the back
side of the upper level ride and ahead of the upper level low and
is poised to move from west to east over northern Alaska today and
Sunday. Favorable upper level jet dynamics will produce heavy
snow over a wide swath over the west coast, interior and north
slope. West and southwest facing terrain especially over the
western Brooks Range and higher terrain over the interior will
receive additional snowfall with favorable upslope componet.

On the surface, a 977 mb low over the western Bering Sea continues
to track north and east with an occluded front stretching north
and east to near the Bering Strait and warm front approaching the
Seward Peninsula at this time. The associated cold front sweeps on
shore along the west coat tonight as the low now weakened to 988
mb moves into the Gulf of Anadyr. Snow and winds are increasing
rapidly over the lower YK delta and southern Seward Peninsula at
this time and will increase later this morning in the western
interior as well as Kotzebue Sound and the western Brooks Range.
Snow and wind will increase this afternoon over the north slope
especially the western north slope where the Blizzard Watch for
the western coast was upgraded to a warning and a Blizzard Warning
was issued for Barrow beginning this afternoon. Snow and blowing
snow meeting advisory level criteria will push north and east
over the rest of the north slope today. A broad area of snow moves
east ahead of the front into the western interior this morning
and into the central interior this afternoon. Snow is expected to
move into the Fairbanks area late this afternoon with snow
becoming heavy this evening and continuing through Sunday morning.
Snow ratios over the interior are slightly less with today`s
model package than with yesterdays model package. Stronger winds
through the profile will also hinder higher snow ratios as
compared to yesterday and slightly lower expected storm total
snowfall over the central interior however warning criteria should
still be reached in the higher terrain north of Fairbanks. The
stronger winds will likely produce blowing and drifting snow with
low visibilities over the highway summits through out the
interior.

The heaviest snow begins to wind down along the west coast tonight
and over the western interior by Sunday morning however lighter
snow accumulations are expected through the day Sunday. The
heaviest snow accumulations are expected to wind down over the
central interior Sunday afternoon and over the western north slope
Sunday evening.

Mid range and extended range models continue to indicate much
colder temperatures over all of northern Alaska next week and
beyond as a deep long wave trough settles over eastern Alaska.
850 mb temperatures over Fairbanks drop from around 13 below
Monday morning to around 22 below Wednesday morning and remain
below 20 below through the end of next week. Surface temperatures
will likely drop into the 20s and 30s below at night with recovery
to near zero during the day next week.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
Winter Storm Warning for AKZ207-AKZ208-AKZ209-AKZ210-AKZ211-
AKZ212-AKZ213-AKZ217-AKZ218-AKZ219-AKZ220-AKZ222.

Blizzard Warning for AKZ201-AKZ202.

Winter Weather Advisory for AKZ203-AKZ204-AKZ205-AKZ206-AKZ214-
AKZ215-AKZ216-AKZ221-AKZ223-AKZ224-AKZ225.

Gale Warning for PKZ210-PKZ230-PKZ235.

Brisk Wind Advisory for PKZ200-PKZ215-PKZ220-PKZ225-PKZ240-
PKZ245.
&&

$$

CCC FEB 17


USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.