Blizzard in Alaska, February 3 to 4, 2004

AREA FORECAST DISCUSSION SOUTHWEST ALASKA
500 PM AST MON FEB 2 2004

.DISCUSSION...

IN THE UPPER LEVELS...AN UNSTABLE FIVE WAVE PATTERN IS ON GOING OVER
THE NORTHERN HEMISPHERE THIS MORNING. A LARGE TROUGH REMAINS OVER THE
BERING SEA WITH A STRONG WAVE MOVING OFF THE MONGOLIAN PLATEAU THIS
MORNING WILL BECOME A PATTERN CHANGER IN THE LONGER TERM OF THE
FORECAST. MAIN ANCHOR IS MAKING A TRANSITION FROM NORTHERN GREENLAND
AND WILL MAKE IT/S 80N 180 BY THE 60 HOUR PERIOD OF THE FORECAST.

ON THE SURFACE...THE LARGEST FEATURE IS THE LARGE UPPER LEVEL AND
SURFACE LOW SOUTH OF ADAK. THIS SYSTEM HAS A FRONT FROM THE WESTERN
ALEUTIANS TO JUST SOUTH OF THE PRIBILOF ISLAND. THE FRONT CONTINUES
EAST TO JUST SOUTH OF COLD BAY AND THEN ARCS BACK TO 30N 180 WITH A
HEALTHY TROPICAL CONNECTION. THE ARCTIC FRONT RUNS FROM CIRCLE CITY
TO WEST OF KING SALMON THEN ANGLES BACK TO ANADYR. THERE ARE A FEW
CIRCULATIONS ALONG THE FRONT NOTED. RIDING IS NOTED OVER THE GULF
AHEAD OF THE FRONT APPROACHING THE AREA FROM THE WEST.

THE MODELS...THROUGH THE FIRST 42 HOURS OF THE FORECAST THE NCEP AND
UKMET MODELS ARE ALL IN FAIR AGREEMENT AT THE SYNOPTIC LEVEL WITH THE
MAJOR FEATURES EFFECTING SOUTHWESTERN AND SOUTH CENTRAL ALASKA. THE
DIFFERENCES AGAIN TODAY OCCUR AT HOUR 48 AND LAST THROUGH 60. IN THE
WEST PREFER THE UKMET. THE UKMET DEVELOPS A SURFACE LOW FASTER AND
STRONGER WITH TIME THAN THE GFS. THE UKMET SOLUTION IS SUPPORTED BY
THE STRENGTH OF THE UPPER WAVE COMING OFF JAPAN. OVER THE EASTERN
DOMAIN EACH MODEL HAS IT/S OWN UNIQUE SOLUTION WILL BLEND THE THREE
INTO A COMBO. THE BASIC SOLUTION WILL BE TO HAVE A TRIANGLE LOW
PRESSURE WITH A LOW NEAR THE BARREN ISLAND ANOTHER NEAR 50N 150W AND
THE OTHER POINT JUST TO THE SOUTH OF COLD BAY. PREFER THE UKMET FOR
THE EASTERN AREAS OF THIS SYSTEM AND THE GFS IN THE NORTH.

THE FORECAST SOLUTION...THE LOW JUST SOUTH OF ATKA WILL PROGRESS AND
SLOWLY FILL UNTIL IT BECOMES A MEMBER OF THE COMPLEX OF LOW PRESSURE
OVER THE WESTERN GULF ALASKA BY 60 HOURS. AN ARCTIC/POLAR BOUNDARY
REMAINS ACROSS THE STATE FROM THE SOUTHWEST CORNER TO THE
NORTHEAST...NORTH AND WEST OF THE BOUNDARY COLDER AND DRIER AIR TO
THE SOUTH AND EAST WARMER AND MORE MOIST AIR RESIDES. THIS FRONT WILL
ACT A FOCUS FOR SNOWFALL ACROSS OUR AREA DURING THE FORECAST PERIOD.
IN THE EASTERN AREAS OF THE SOUTHERN ALASKA COAST LOOK FOR THE
SHOWERY PATTERN TO CONTINUE AS THE UPPER FLOW REMAINS SOUTH TO
SOUTHWEST.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...WIND ADVISORY 155 181 185 191 195
MARINE...GALE...150 155 170 175 176 179 185
      ...STORM...172
      ...HEAVY FREEZING SPRAY...179 185
FIRE WEATHER...NONE

PROTON FEB 04