Blizzard in Alaska, January 26, 2008

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
200 PM AST SAT JAN 26 2008

.ANALYSIS AND MODEL DISCUSSION...
MODELS INITIALIZED WELL THIS MORNING AND CONTINUE ON TRACK WITH THE
LARGE LOW OVER THE WESTERN ALEUTIANS. THE ACCOMPANYING FRONT MOVING
ACROSS THE EASTERN BERING CURRENTLY IS ALSO HANDLED WELL. STEPPED
BACK ON THE TIMING FOR THE BLIZZARD WARNING ALONG THE KUSKOKWIM COAST
AND WESTERN CAPES WITH THE TIMING A LITTLE LATER THAN LAST NIGHTS
MODEL GUIDANCE. THE LOW IN THE EASTERN GULF COMBINED WITH COLD
ADVECTION OVER SOUTH CENTRAL HAS PRODUCED STRONG WINDS ESPECIALLY
THROUGH GAPS TODAY. THE GULF LOW WILL MOVE OUT TONIGHT WITH WINDS
DIMINISHING OVER THE NORTHERN GULF COAST. BEYOND TONIGHT...THE MODELS
CONTINUE GOOD AGREEMENT THROUGH MONDAY MORNING. SOME DISCREPANCY
EXISTS WITH HOW A LOW DEVELOPS AND PROGRESSES MONDAY THROUGH TUESDAY
ACROSS THE GULF. THIS IS A LOW THAT DEVELOPS OFF THE BERING SEA LOWS
FRONT. ALL MODELS HAVE A LOW DEVELOPING IN THE WESTERN/SOUTHWESTERN
GULF MONDAY AFTERNOON. THE DIFFERENCE IS THAT THE 12Z GFS KEEPS A LOW
IN THE CENTRAL GULF AND THEN MOVES IT SOUTHEAST THROUGH TUESDAY. THE
NAM KEEPS A MORE ELONGATED LOW FROM THE NORTHERN GULF THROUGH THE
GULF INTO TUESDAY. THE ECMWF AND UKMET MOVE OFF THE LOW RATHER
QUICKLY TO THE SOUTHEAST SINCE THEY DEVELOP A SECOND LOW NEAR THE JET
EXIT REGION WHICH SLIDES THE LOW EAST FAST. BY TUESDAY NIGHT
HOWEVER...A NEW LOW SLIDES ACROSS THE SOUTHERN GULF ALONG THE JET
AXIS WITH ANOTHER LOW MOVING INTO THE BERING.  THE DIFFERENCES HERE
ARE ON THE TIMING OF THE MOVEMENT OF THIS LOW. RIGHT NOW PREFER A GFS
SOLUTION SINCE A LOW WILL FORM IN THE WESTERN GULF AND LIKELY REMAIN
SINCE DETACHED FROM JET ENERGY AND SLOWLY SLIDE EAST AND DISSIPATE
TUESDAY EVENING. OUT WEST...THE DIFFERENCES ARE MINIMAL EXCEPT ON THE
TIMING OF THE LOW MOVING OUT OF THE PACIFIC. STILL PREFER SLOWER
TIMING OF THE GFS SINCE EACH RUN HAS TRENDED A BIT SLOWER AND DEEPER
AND THIS FITS STRONGER JET WITH THE MODELS.

.UPPER LEVELS...
MAJOR STORY IS THAT THE LARGE AMPLITUDE LOW OVER THE BERING TO WEAKEN
AS THE FRONT MOVES INTO THE MAINLAND AND GULF TONIGHT AND TOMORROW.
THE FLOW THEN BECOMES MORE ZONAL WITH TIMING AN ISSUE FOR THE TUESDAY
STORM MOVING OUT OF THE NORTHERN PACIFIC AND INTO THE GULF WEDNESDAY.
THE FLOW BECOMES MORE AMPLIFIED BEHIND THIS FEATURE WITH A LARGE LOW
ONCE AGAIN MOVING INTO THE WESTERN BERING AND THE LOW IN THE GULF
REMAINING NEAR THE SOUTHERN PANHANDLE. EVENTUALLY ON FRIDAY/SATURDAY
WE MOVE THROUGH THE SAME PROGRESSION WE WILL HAVE SUNDAY THROUGH
TUESDAY CURRENTLY.

.SHORT TERM FORECAST...
SOUTH AND EAST OF THE ALASKA RANGE...
LOW PRESSURE ALONG THE NORTHERN GULF COAST WITH HIGH PRESSURE AND
COLD AIR INLAND. THESE CONDITIONS HAVE PRODUCED STRONG WINDS THROUGH
GAPS OF SOUTH CENTRAL. IN ADDITION...THE FRESH SNOW FROM YESTERDAY
HAS LED TO MANY AREAS OF BLOWING SNOW. BLIZZARD CONDITIONS REMAIN
THROUGH THOMPSON PASS AND GAPS NEAR THE TOWN OF VALDEZ. THE LOW WILL
PULL OFF TONIGHT WITH WINDS GRADUALLY DECREASING FROM THE WEST. THEN
HIGH PRESSURE AND LOWER WIND SPEEDS TO RULE TONIGHT WITH TEMPERATURES
DROPPING WELL BELOW ZERO OVER MUCH OF SOUTH CENTRAL. A FRONT TO REACH
TO KODIAK TOMORROW WITH WINDS PICKING UP FROM THE SOUTHEAST. THE
FRONT TO REACH THE NORTHERN GULF COAST SUNDAY NIGHT WITH A TYPICAL
DOWNSLOPE PRECIP PATTERN WITH MOST PRECIP BEING ON THE EASTERN SIDE
OF THE KENAI PENINSULA AND UP IN THE WESTERN SUSITNA. SOME MODERATE
WINDS TO ACCOMPANY THE FRONT ALONG THE COAST AND THROUGH TURNAGAIN
ARM MONDAY AND FARTHER SOUTH SUNDAY EVENING AND NIGHT. THE MAIN LOW
TO MOVE SOUTH AND EAST TUESDAY INTO WEDNESDAY LEAVING THE FRONT AND
PRECIP TO DISSIPATE OVER SOUTH CENTRAL TUESDAY.

WESTERN ALASKA...
A FRONT WORKING ACROSS THE EASTERN BERING TO HIT THE COAST THIS
EVENING. SOME PRECIP ALREADY WORKING INTO THE KUSKOKWIM DELTA THIS
AFTERNOON. WINDS WILL PICK UP THIS EVENING AND LIKELY BRING BLIZZARD
CONDITIONS FROM THE WESTERN CAPES THROUGH THE YK DELTA COASTAL
REGIONS. THE FRONT TO WEAKEN AS IT MOVES INLAND TOMORROW BUT WARM UP
THE INTERIOR A BIT. HOWEVER...WINDS TO BE MODERATE ALONG THE COAST
THROUGH THE DAY. PRECIP TO SPREAD INTO THE KUSKOKWIM VALLEY AS
WELL TOMORROW NIGHT. A SECONDARY FRONT TO PUSH SOME COLDER AIR TO THE
COAST MONDAY AND SOME PRECIP AS WELL. PRECIP TO WANE AS THE FRONT
DISSIPATES OVER THE MAINLAND MONDAY NIGHT AND TUESDAY. DRIER
CONDITIONS TO PREVAIL TUESDAY AFTERNOON INTO WEDNESDAY.

ALEUTIANS AND BERING...
LARGE LOW OVER THE WESTERN BERING WITH A FRONT MOVING THROUGH THE
CENTRAL AND EASTERN BERING THIS AFTERNOON. MODERATE WINDS ARE BEING
EXPERIENCED OVER THE EASTERN ALEUTIANS AND CENTRAL BERING. THE WINDS
TO MOVE TO THE COAST THIS EVENING AND BRISTOL BAY AREA TOMORROW. THE
LARGE LOW TO HAVE MANY WAVES ROTATE AROUND THROUGH THE BERING AND
ALEUTIANS SUNDAY THROUGH TUESDAY. THE LOW IN THE MEANTIME MOVES NORTH
OF 60N NEAR 180 SUNDAY AND THEN TOWARDS ST LAWRENCE ISLAND MONDAY
NIGHT WEAKENING THE WHOLE TIME. WINDS WILL BE MODERATE FROM THE WEST
OVER THE ENTIRE BERING WITH SHOWERS AND MORE ORGANIZED PRECIP NEAR
THE SHORT WAVE TROUGHS. A STRONG LOW WILL MOVE OUT OF THE NORTH
PACIFIC TUESDAY TOWARD THE CENTRAL ALEUTIANS. THE TIMING OF THIS
SYSTEM IS STILL IN DOUBT BUT IT WILL BRING STRONG WINDS TO THE
CENTRAL AND EASTERN ALEUTIANS TUESDAY AND TUESDAY NIGHT.

.LONG TERM FORECAST...
THE BIG FEATURES OF A LARGE LOW IN THE EASTERN GULF AND IN THE
WESTERN BERING WEDNESDAY THROUGH SATURDAY ARE THE STORY. A FRONT WILL
WORK THROUGH THE BERING DURING THAT TIME FRAME AND TO THE MAINLAND
SATURDAY. GENERALLY...WINDY AND LOTS OF UNSETTLED WEATHER OVER THE
BERING. DRY AND COLD OVER THE MAINLAND EXCEPT WHEN THE FRONT REACHES
THE WEST COAST SOMETIME LATE FRIDAY AND INLAND SATURDAY.
TIMING...EXACT LOCATIONS OF THE FRONT AND INTENSITY ARE STILL IN
DOUBT.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...BLIZZARD WARNING ZONES 131 155 AND 161
         HIGH WIND WARNING ZONE 135
MARINE...GALE 160 170 172 175 176 180 185
FIRE WEATHER...NONE

JN JAN 08