Gale Warning 141, NWS Juneau, AK

SOUTHEAST ALASKA FORECAST DISCUSSION
1115 AM ADT MON MAR 19 2007

.SYNOPSIS...
.SHORT RANGE...A LOW MOVING NORTH ACROSS THE QUEEN CHARLOTTE
ISLANDS EARLY THIS MORNING IS MOVING ACROSS THE SOUTHEAST CORNER
OF THE PANHANDLE AS WELL AS IT MOVES INTO BRITISH COLUMBIA.
LIGHT SNOW FALLING ACROSS MUCH OF THE SOUTHERN PANHANDLE ALTHOUGH
THE SOUTHERN PORTIONS ARE CLOSE IT SEEMS TO CHANGING TO A RAIN OR
MIX OF RAIN/SNOW.  HAVE UPDATED THE FORECAST THIS MORNING TO TRIM
THE SNOW FALL OVER THE SITKA/ANGOON/JUNEAU ZONES FOR TODAY.

THE UPPER LEVEL TROUGH WHICH IS NEGATIVELY TILTED ACROSS THE
EASTERN GULF/SOUTHEAST ALASKA WILL LIFT ACROSS THE PANHANDLE INTO
BRITISH COLUMBIA BY TUESDAY. SOME SCATTERED AREAS OF SNOW SHOWERS
ARE POSSIBLE AS THE UPPER LEVEL TROUGH MOVES ACROSS THE AREA.
AMOUNTS FROM THE SHOWERS COULD VARY SIGNIFICANTLY.

A RIDGE BEING MOVED IN ADVANCE OF THE NEXT SYSTEM WILL SPREAD
INTO THE GULF OF ALASKA TUESDAY. WINDS ASSOCIATED WITH THE
INCOMING SYSTEM ARE INCREASING UP TO OR NEAR GALES FOR LATE
TUESDAY IN THE OFF SHORE WATERS.

.LONG RANGE...CONSIDERABLE DIFFERENCES EXIST AMONGST THE MODEL
SOLUTIONS WITH THE NEXT MAJOR SYSTEM NOW EVOLVING OVER THE
NORTHERN PACIFIC. ALL THE MODELS APPEAR TO BE CONSISTENT WITH
MOVING THE SYSTEM INTO THE GULF THROUGH MID WEEK...BUT THE MAJOR
DIFFERENCE IS WHERE THE SYSTEM MAKES LANDFALL OVER SOUTH CENTRAL
ALASKA. THE GFS AND NAM PRETTY MUCH TAKE THE SAME PATH ACROSS THE
NORTHERN GULF AND MOVE INLAND JUST TO THE WEST OF YAKUTAT BAY.
THE ECMWF IS A BIT FARTHER WEST AND TAKES THE SYSTEM INLAND IN
THE VICINITY OF PRINCE WILLIAM SOUND. NEEDLESS TO SAY...THERE IS
NOT A TREMENDOUS AMOUNT OF CONFIDENCE WITH FORECAST BEYOND THE
DAY 3 PERIOD. THEREFORE...NOT ANTICIPATING MUCH IN THE WAY OF
CHANGE IN THE CURRENT FORECAST PAST THE DAY 3 PERIOD.

IT DOES STILL LOOK LIKE WE WILL SEE A CHANGE IN THE PATTERN
ACROSS SOUTHEAST ALASKA. REGARDLESS OF THE EXACT PATH OF THE
ABOVE MENTIONED LOW...IT WILL STILL ALLOW A WARM FRONT TO LIFT
NORTHWARD ACROSS THE PANHANDLE. AS A RESULT...SNOW IS EXPECTED TO
TURN FROM SNOW TO RAIN FAIRLY QUICKLY AS THE WARMER AIR SPREADS
NORTHWARD ACROSS THE PANHANDLE.

PRECIPITATION IS EXPECTED TO START AFFECTING THE PANHANDLE LATE
TUESDAY NIGHT. THE GFS AND NAM SOLUTIONS SHOW ONSHORE FLOW MORE
NORMAL TO THE COAST WHILE THE ECMWF WOULD HAVE A MORE OF A
SOUTHERLY OR SOUTHEASTERLY COMPONENT. AS A RESULT...THE GFS AND
NAM PRODUCE SIGNIFICANT AMOUNTS OF QPF OVER THE PANHANDLE REGION.
THE MAIN QUESTION WILL BE HOW MUCH SNOW WILL FALL OVER THE
NORTHERN AND CENTRAL PANHANDLE BEFORE CHANGING TO RAIN.

.AJK...WATCHES/WARNINGS/ADVISORIES
PUBLIC...NONE
MARINE...SMALL CRAFT ADVISORY PKZ041>043-051