Small Craft Advisory 596, NWS Juneau, AK

SOUTHEAST ALASKA FORECAST DISCUSSION
1100 AM AST SUN DEC 9 2007

.SYNOPSIS...
.SHORT RANGE...THE LATEST SATELLITE IMAGERY SHOWS SOME CLEARING
SKIES NEAR PAYA AND OVER THE FAR NORTHERN AREAS...MOST OF THE
REST OF THE PANHANDLE IS UNDER MID TO LOW LEVEL CLOUDS. THERE IS
SOME LARGER BREAKS IN THE CLOUD COVER OVER THE POW ATTM. A UPPER
RIDGE WILL CONTINUE MOVE OVER THE AREA THIS EVENING. THIS WILL
INCREASE THE NORTHWEST FLOW ALOFT SO THIS WILL KEEP THE PANHANDLE
ON THE DRIER SIDE AND THE BREAKS IN THE CLOUD COVER WILL INCREASE
IF PLACES CAN MIX OUT THE LOWER CLOUDS. WINDS TODAY WILL BE ON
THE LIGHT SIDE WITH NO MORE THAT 15 KT.

THE BOUNDARY LAYER IS VERY MOIST AND WITH LITTLE CLOUDS ALOFT
THIS WILL BE A PERFECT SITUATION FOR AREAS OF FOG TO FORM
TONIGHT. SO WILL PUT IN AREAS OF FOG FOR MOST AREAS THROUGH
TONIGHT. SOME HIGHER CIRRUS CLOUDS WILL BEGIN TO MOVE OVER THE
AREA LATER ON TONIGHT IN ADVANCE OF AN APPROACHING WEATHER FRONT
FROM THE SOUTHWEST AND MAY BREAK UP THE FOG IN PLACES LATE
TONIGHT.

A DEVELOPING SURFACE LOW OVER THE NORTH PACIFIC ATTM WILL DEEPEN
TO AROUND 975MB BY MON AFTERNOON AND BE NORTHEAST OF KODIAK. THE
ASSOCIATED WEATHER FRONT WILL LIFT INTO THE EASTERN GULF THROUGH
MON AFTERNOON. THE FRONT HAS STRONG UPPER LEVEL JET SUPPORT ALONG
WITH A SUB-TROPICAL MOISTURE CONNECTION SO IT WILL BE A VERY WET
AND WINDY. WITH THAT SAID...A BARRIER JET TO 50KT WILL DEVELOP
EARLY MON MORNING ALONG THE NORTHERN GULF AND PERSIST THROUGH THE
DAY. THE REST OF THE EASTERN GULF WILL SEE MIN TO MAX GALES FROM
SOUTH TO NORTH. RAIN WILL BEGIN TO DEVELOP OVER THE COASTAL AREAS
THROUGH THE MORNING HOURS WITH THE WINDS INCREASING. PAYA MAY SEE
SOME MIXED RAIN AND SNOW WHEN THE PRECIP FIRST STARTS BUT WILL
CHANGE OVER TO ALL RAIN BY THE LATE MORNING. THE RAIN WILL MOVE
OVER THE REST OF THE PANHANDLE THROUGH MON WITH WINDS BECOMING
BREEZY TO WINDY. THE COASTAL AREAS WILL SEE WIND ADV GUSTS
BEGINNING IN THE MORNING IN THE NORTH AND SLIDING SOUTHWARD
THROUGH THE DAY. THE PRESSURE GRADIENT WILL BE EAST/WEST SO THOSE
MARINE CHANNELS WILL SEE WINDS PICK UP TO SMALL CRAFT WINDS
THROUGH THE DAY. FOR P-TYPE IT MAY BE COLD ENOUGH FOR SNOW IN THE
MORNING BUT BY THE AFTERNOON MOST AREAS WILL HAVE CHANGED TO ALL
RAIN. THE AREAS THAT MAY STAY ALL SNOW WILL BE UP IN THE FAR
NORTHERN INNER CHANNELS AS THINK THEY WILL KEEP A NORTHERLY WIND
BUT THINK THE SNOW FALL AMOUNTS WILL BE ON THE LOWER SIDE AS THE
SNOW RATIO WILL BE NEAR 7 TO 1. HYDER WILL WILL REMAIN ALL SNOW
THROUGH THE MON AFTERNOON AS THERE SOME VERY COLD STILL OVER
CENTRAL BC. HYDER WILL KEEP A EAST WINDS TO CONTINUE TO ADVECT
THESE COLDER TEMPS AND KEEP THEM WELL BELOW FREEZING. SNOW
AMOUNTS WILL REMAIN BELOW ADV AS MOST OF THE PRECIP WILL BE OVER
MON NIGHT.

.LONG RANGE...FRONT WILL CONTINUE TO SLIDE ACROSS THE PANHANDLE
MONDAY NIGHT.  RAIN WILL PERSIST EVERYWHERE EXCEPT ALONG THE
INTERIOR VALLEYS NEAR THE BORDER SUCH AS THE HYDER AREA AND THE
CHILKAT VALLEY WHERE COOLER AIR WILL REMAIN ENTRENCHED.  EXPECT
SEVERAL INCHES OF SNOW BEFORE IT CHANGES OVER TO RAIN OVERNIGHT.
WINDS WILL BE DIMINISHING OVERNIGHT AS WELL...WITH ADVISORY LEVEL
GUSTS EXPECTED IN ZONES 27 AND 28 THROUGH THE NIGHT.

BEHIND THE FRONT...THE LOW WILL DISSIPATE AND MOVE EASTWARD
ACROSS THE NORTHERN GULF.  SHOWERS AND SLIGHTLY COOLER
TEMPERATURES WILL FOLLOW TUESDAY AND TUESDAY NIGHT.  A FLATTENED
RIDGE OVER THE EASTERN GULF QUICKLY GIVES WAY TO YET ANOTHER LOW
FORMING IN THE WESTERN GULF.

THE OCCLUSION ASSOCIATED WITH THE WESTERN GULF LOW MOVES INTO THE
GULF WEDNESDAY AND ACROSS THE PANHANDLE WEDNESDAY NIGHT.  GALE
FORCE WINDS ARE EXPECTED IN THE OUTSIDE WATERS WHILE SMALL CRAFT
WINDS FORM IN THE COASTAL WATERS.  WEAK WARM AIR ADVECTION WILL
ALLOW PRECIPITATION TYPE TO BE MAINLY A MIX IN THE NORTH AND RAIN
TO THE SOUTH.  LIKE THE FORMER LOW...THIS LOW WEAKENS OVER THE
NORTHERN GULF AND SLIDES EASTWARD ACROSS THE PANHANDLE.

ALL LONG RANGE MODELS POINT TO AT LEAST SOME RIDGING OVER THE
EASTERN GULF FRIDAY AND FRIDAY NIGHT.  LEFT MAINLY CHANCE POPS
OVER THE PANHANDLE DURING THIS TIME WITH THE POSSIBILITY OF
OFFSHORE FLOW SETTING UP.  ADDITIONALLY...THIS SHOULD ALLOW
COLDER AIR TO ADVECT INTO THE AREA...PARTICULARLY IN THE NORTH.
HANKO

.AJK...WATCHES/WARNINGS/ADVISORIES
PUBLIC...NONE

MARINE...SCA...ENTIRE COASTAL AREAS PKZ21-22-34-35