Blizzard and Heavy Snow in Alaska, March 5 to 7, 2007

SOUTHEAST ALASKA FORECAST DISCUSSION
1100 AM AST MON MAR 5 2007

.SYNOPSIS...
.SHORT RANGE...FIRST LOW MOVING NORTH JUST WEST OF CHICHAGOF
ISLAND MONDAY MORNING PASSING OVER THE CROSS SOUND REGION AROUND
10 AM.  WRAP AROUND BAND FINALLY PUSHED FAR ENOUGH WEST TO BRING
A PERIOD OF HEAVY SNOW FALL INTO YAKUTAT. PICKED UP A QUICK 2
INCHES THIS MORNING AND ISSUED SNOW ADVISORY THROUGH THE
AFTERNOON THAT WILL BE ENDING. EXPECT THE GUSTY OUTFLOW WINDS
FROM THE INTERIOR PASSES TO CONTINUE THROUGH TUESDAY SO WILL BE
EXTENDING THAT THROUGH TUESDAY.

LOOKED AS IF THE NAM INITIALIZED BEST OVER THE EASTERN GULF WITH
OUR CONTINUED TRAIN OF LOWS MOVING NORTHWARD.  NAM SEEMED TO HAVE
BETTER HANDLE ON THE LOW JUST PASSING BUOY 46184 THIS MORNING.
EXPECT THAT THIS LOW WILL STAY ALONG 140W AS IT MOVES
NORTH...THEN CURVING NORTHWEST TOWARDS MIDDLETON ISLAND TUESDAY.
THEREFORE MAY KEEP THE BEST MOISTURE ASSOCIATED WITH IT GENERALLY
OFF SHORE THE PANHANDLE.

RAIN SNOW LINE THIS MORNING GOES FROM NORTH OF SITKA TO FREDERICK
SOUND NORTH OF KAKE AND THEN INTO SOUTHERN STEPHENS PASSAGE...BUT
A POCKET OF COLD AIR SEEMS TO BE LINGERING AROUND WRANGELL
AIRPORT THIS MORNING. WILL BE LETTING THE FREEZING RAIN ADVISORY
EXPIRE FOR ZONE 26.

FOR THE ANGOON AREA TEMPERATURES ARE WARMING AND NOW INTO THE
UPPER 20S... WILL NOT BE ADJUSTING THE SNOW WARNING FOR THERE DUE
TO EXPIRE EARLY THIS AFTERNOON.

ANOTHER BURST OF HEAVIER SNOW ACROSS THE NORTH CENTRAL PANHANDLE
AS THE REMAINS OF THE LOW MOVES NORTH TO CANADA...EXPECT TO SEE
THE WINTER STORM WARNINGS EXPIRE THIS EVENING AS EXPECTED SO FAR.

WITH THE WARMING HEADED NORTH AS WELL... TONIGHT FORECAST TRICKY
AS TO THE TYPE.  STILL A POTENTIAL FOR SOME FREEZING
PRECIPITATION I THINK IN THE GUSTAVUS AREA BUT WILL BE CHECKING
ON THAT THROUGH THE AFTERNOON. OVER ALL THE IDEA OF ANOTHER 4 TO
8 INCHES ACROSS THE NORTHERN THIRD IS QUITE PLAUSIBLE.

THE FRONTAL BAND FROM THE FURTHER SOUTH AND MUCH STRONGER LOW
WILL BEGIN TO LIFT INTO THE SOUTHERN PANHANDLE TUESDAY MORNING
BRINGING WITH IT MORE RAIN...AND THE FRONT SHOULD BE MOVING UP
INTO THE NORTH CENTRAL PANHANDLE BY AFTERNOON SO RAIN AND OR SNOW
AT LEAST OVER THE NORTH TIER.

.LONG RANGE...NOT MUCH CHANGE IN THE LONG WAVE PATTERN MID WEEK
THROUGH EARLY NEXT WEEK...WHICH MEDIUM RANGE MODELS ARE IN PRETTY
GOOD AGREEMENT ON. A HIGH AMPLITUDE UPPER LEVEL RIDGE/HIGH WILL
DOMINATE FROM THE ALEUTIANS NORTHWARD...WHILE A LARGE SCALE UPPER
LEVEL LOW WILL BE CENTERED OVER THE GULF OF ALASKA MID WEEK ONLY
TO BE REPLACED BY ANOTHER UPPER LEVEL LOW THAT WILL DROP SOUTH
INTO THE GULF LATE WEEK AND LINGER THERE THROUGH EARLY NEXT WEEK.
SEVERAL LOW PRESSURE SYSTEMS WILL AFFECT THE FORECAST AREA
THROUGH THE LONG RANGE.

THE FIRST SYSTEM...A DEEP LOW IN THE 960S OVER THE EASTERN GULF
WILL MOVE INTO THE NORTHWEST GULF TUE NIGHT AND WED...THEN
DISSIPATE THERE WED NIGHT INTO THU. IT IS STILL LOOKING LIKE A
STRONG BAND OF HIGH GALES TO STORM FORCE WINDS WILL MOVE OVER THE
NORTHERN AND EASTERN GULF TUE NIGHT AND WED WITH 25 TO 35 FOOT
SEAS SPREADING NORTH. WIND ADV GUSTS LOOK HIGHLY LIKELY ALONG THE
COASTAL AREAS TUE NIGHT AND WILL CONTINUE OVER THE NORTHEAST GULF
COAST THROUGH WED EVENING. THE GRADIENT WILL FINALLY RELAX OVER
THE REMAINDER OF THE PANHANDLE TUE NIGHT AND PUT AND END TO THE
STRONG NORTHERLIES THAT HAVE PERSISTED FOR SO LONG.

THE ARCTIC AIR WILL RETREAT OUT OF THE FORECAST AREA AS A BAND OF
PRECIP MOVES INTO THE PANHANDLE. PRECIP TYPE WILL BE MAINLY RAIN
OVER MOST AREAS. TRICKIEST AREA WITH BE THE SKAGWAY AND HAINES
AREAS FOR PRECIP TYPE. A WARM LAYER ABOVE FREEZING MAY MAKE IT UP
THERE AND CHANGE PRECIP TO RAIN WHILE SURFACE TEMPS STRUGGLE TO
GO ABOVE FREEZING TUE NIGHT AND EARLY WED. WILL MENTION SNOW AND
FREEZING RAIN. COLD AIR WRAPS BACK IN OVER THE PANHANDLE WED
NIGHT AND TRANSITIONS TO RAIN AND SNOW SHOWERS.

THE SECOND LOW...AS THE NEXT UPPER LEVEL LOW DROPS SOUTH A LOW IN
THE 970S WILL DEVELOP OVER THE EASTERN GULF FOR THU AND THU
NIGHT...THEN WEAKENS AND MOVES INTO THE NORTHWEST GULF ON FRI.
COLDER AIR CONTINUES TO SPREAD INTO ALL AREAS WITH POTENTIAL FOR
A GOOD SNOWFALL EVENT OVER THE ENTIRE PANHANDLE THU THROUGH FRI.
SMALL CRAFT TO GALE FORCE WINDS WILL OCCUR OVER THE OUTSIDE
WATERS BOTH NORTH AND SOUTH OF LOW THU NIGHT WITH SMALL CRAFT
WINDS POSSIBLE OVER PORTIONS OF THE INNER CHANNELS.

A THIRD LOW WILL POTENTIALLY MOVE NORTH INTO THE EASTERN GULF FOR
THE WEEKEND WHERE THE AIRMASS WILL REMAIN COLD FOR SNOW IN MOST
AREAS. HIGH PRESSURE TO THE NORTH MAY START BUILDING BACK IN OVER
THE NORTHERN PANHANDLE LATE WEEKEND INTO EARLY NEXT WEEK AND
BRING SOME ARCTIC AIR BACK INTO THE NORTHERN AREAS.

.AJK...WATCHES/WARNINGS/ADVISORIES
PUBLIC...HEAVY SNOW WARNING ENDING THIS AFTERNOON AKZ024
         WINTER STORM WARNING ENDING LATE THIS AFTERNOON
               AKZ018>022-025
         WIND ADVISORY EXNTEND THROUGH TUESDAY AFTERNOON AKZ017
         SNOW ADVISORY ENDING THIS AFTERNOON AKZ017
         FREEZING RAIN ADVISORY ENDING THIS AFTERNOON FOR AKZ026

MARINE...CURRENT GALES PKZ011>013-021-022-031-032-036-041-051
      ...CURRENT SMALL CRAFT PKZ033>035-042-043-053
      ...CURRENT HEAVY FREEZING SPRAY WARNING PKZ011>013

BMB/TAR