High Wind in Alaska, January 10 to 13, 2005

AREA FORECAST DISCUSSION SOUTHWEST ALASKA
500 AM AST MON JAN 10 2005

.DISCUSSION...

UPPER LEVEL OMEGA BLOCK BEING SLOWLY FLATTENED THIS MORNING AS THE
ARCTIC LOW MOVES INTO NORTHERN CANADA. UPPER HIGH PERSISTS OVER THE
AK PEN WHILE TROUGHS OVER THE EASTERN AND NORTHWESTERN PACIFIC REMAIN
IN PLACE. SURFACE FEATURES INCLUDE SOUTHERLY FLOW WITH PLENTY OF
MOISTURE OVER THE WESTERN AND CENTRAL ALEUTIANS...AND AREAS OF FOG
ALONG THE NORTH GULF COAST AND COOK INLET. THE ARCTIC FRONT IS MOVING
SOUTH OVER MUCH OF THE SOUTHERN HALF OF THE STATE AS A SURFACE
REFLECTION OF THE FLATTENING RIDGE ALOFT.

MODELS ARE IN GOOD AGREEMENT THROUGH ROUGHLY 72 HOURS. THE ARCTIC
FRONT OVER EASTERN ZONES WILL BRING SUBSTANTIAL COOLING...WITH 850
TEMPERATURES FALLING TO AT LEAST 15 TO 25 BELOW BY TONIGHT AND
PERSISTING THROUGH MOST OF WEDNESDAY. COLD ADVECTION AND A STRONG
PRESSURE GRADIENT WILL BRING ADVISORY LEVEL WINDS TO THOMPSON PASS
AND THE COPPER RIVER DELTA BEGINNING TODAY.

IN WESTERN ALASKA THE ARCTIC FRONT WILL NOT MAKE MUCH MORE
HEADWAY...HAVING ALREADY CROSSED THE KUSKOKWIM DELTA AND VALLEY. IT
WILL REACH AS FAR SOUTH AS ILIAMNA BEFORE STALLING THROUGH WEDNESDAY.

OVER THE BERING AND ALEUTIANS SEVERAL LOWS ROTATING AROUND EACH OTHER
WEST OF SHEMYA WILL SEND TWO FRONTS EASTWARD. THE SOUTHERLY STREAM OF
MOISTURE OVER THE WESTERN AND CENTRAL ALEUTIANS ASSOCIATED WITH THE
FIRST FRONT WILL MAKE LITTLE HEADWAY AGAINST THE AK PEN RIDGE UNTIL
LATER ON TUESDAY WHEN SOME SNOW MAY REACH THE MAINLAND. THE SECOND
FRONT CROSSING THE ALEUTIANS SHOULD REACH WESTERN ALASKA WEDNESDAY
BRINGING SNOW WITH SOME RAIN ALONG THE COAST LATE IN THE DAY.

AT THIS POINT THE MODELS DIVERGE. THE GFS APPEARS TO BE TOO FAST IN
BREAKING DOWN THE REMNANTS OF THE RIDGE AND BRINGING A LOW ACROSS THE
STATE. THE MESOETA AND UKMET ARE IN BETTER AGREEMENT IN KEEPING THE
LOW BACK IN THE BERING WITH THE RIDGE STILL INTACT OVER THE EASTERN
HALF OF THE FORECAST AREA. THIS SOLUTION ESSENTIALLY INVOLVES LOWS
PINWHEELING THEIR WAY ACROSS THE NORTHERN PACIFIC WITH SUBSTANTIAL
PRECIPITATION AND WIND FOR THE ALEUTIANS...BUT NOT MUCH ACTIVITY IN
THE EAST. WENT WITH A MODEL BLEND THAT EMPHASIZED THIS LESS DRAMATIC
SOLUTION.

IN THE EXTENDED...THIS IDEA WAS CONTINUED THROUGH THE FIRST 5
DAYS...WHICH RESULTS IN MOISTURE LADEN FLOW INTO MUCH OF THE FORECAST
AREA WITH GRADUAL WARMING. BY NEXT WEEKEND THE PINWHEELING LOWS WILL
PROVIDE WARM AND WET ONSHORE FLOW FOR THE GULF COAST.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...NONE
MARINE...HEAVY FREEZING SPRAY AREAS 8 AND 14
         GALE WARNING AREA 14
FIRE WEATHER...NONE

DS JAN 05