Gale Warning 210, NWS Juneau, AK

SOUTHEAST ALASKA FORECAST DISCUSSION
1130 AM ADT THU SEP 13 2007

.SYNOPSIS...
.SHORT RANGE...WEAKENING FRONTAL SYSTEM MAKING NORTHERN PANHANDLE
CLOUDY WHILE HIGH PRESSURE OVER SOUTHERN PANHANDLE KEEPING SKIES
CLEAR...EXCEPT WHERE FOGGY. PRECIPITATION WITH THE FRONT WAS
CONFINED TO FAR NORTH PART OF FCST AREA...YAKUTAT HAD 1/4 INCH
OVERNIGHT. AT 18Z THE FRONTAL BOUNDARY WAS FROM ROUGHLY SKAGWAY
TO SITKA BASED ON SATELLITE IMAGERY AND SFC OBSERVATIONS OF
PRESSURE TENDENCIES AND WIND SHIFTS. FROM ABOUT FREDERICK SOUND
SOUTH SKIES WERE CLEAR ALL NIGHT. VISIBLE SATELLITE IMAGES SHOW
WIDESPREAD SHALLOW FOG STILL EXISTS OVER SUMNER STR...MOST OF
CLARENCE STR AND EASTERN FREDERICK SND.

THE COMPLEX MIX OF RADIATION FOG/STRATUS AND MID LEVEL FRONTAL
CLOUDS ARE MAKING AVIATION FCSTS TRICKY THIS MORNING. FOG OR VERY
LOW CLOUDS FORMED OVERNIGHT IN ICY STR CROSS SND AND LYNN CANAL
BEFORE FRONTAL CLOUDS MOVED IN. ONSHORE GRADIENTS AND NW SFC
WINDS BEHIND THE FRONT ARE PUSHING LOW STRATUS INTO COASTAL
AREAS. BASED ON OBS FROM HOONAH AND ELFIN COVE THIS MORNING IT
APPEARS THE FRONT HAS JUST ENOUGH LIFTING WITH IT TO ACT ON THE
LOW STRATUS IN ICY STR AND CROSS SND TO CAUSE A FEW SPRINKLES OR
LIGHT RAIN.

ALL MODELS SHOW RAPID EASTWARD MOVEMENT OF THE DYING FRONTAL
SYSTEM TODAY AND HIGH PRESSURE BUILDING IN STEADILY AGAIN OVER
THE NEXT 24HRS. FORECAST SOUNDINGS FOR NORTHERN PANHANDLE DEPICT
SUBSIDENCE DRYING FROM ALOFT THROUGH THIS EVENING. THIS WILL KEEP
CIGS/VSBYS ON THE LOW SIDE UNTIL SKIES EVENTUALLY SCATTER OUT
LATE AFTERNOON AND EVENING ONLY TO ALLOW RADIATION FOG TO FORM
AGAIN THUR NIGHT.

THE SOUTHERN PANHANDLE MAY SEE A FEW MID LEVEL CLOUDS THIS
EVENING FROM THE DEPARTING. THE APPRCHG FRONT DYNMAICS...EVEN AS
WEAK AS THEY ARE...WILL LIKELY BE THE MECHANISM TO STIR UP AND
CLEAR OUT THE MARINE FOG THIS AFTERNOON. BUT IT WILL REFORM AGAIN
TONIGHT. ON FRIDAY THE HIGH WILL MAKE FOR A VERY STABLE DAY
ACROSS THE PANHANDLE IN ADVANCE OF A SIGNIFICANT STORM THIS
WEEKEND.

.LONG RANGE...SUN NIGHT THROUGH SAT WILL FEATURE A MAJOR STORM
SYSTEM MOVING INTO THE GULF OF ALASKA. A LOW WILL DEEPEN INTO THE
MID 980S AS IT MOVES NORTH ACROSS THE CENTRAL GULF...THEN WEAKEN
SLIGHTLY OVER THE NORTH-CENTRAL GULF THROUGH SAT AFTERNOON. THE
OCCLUDED FRONT WILL MOVE ACROSS THE PANHANDLE FRI NIGHT THROUGH
EARLY SAT. BIGGER MODEL DIFFERENCES SHOW UP SAT NIGHT THROUGH SUN
WITH THE LOW. PREFER TO STICK WITH THE ECMWF AND NAM SOLUTIONS
WHICH KEEP THE LOW OVER THE GULF AND WEAKEN IT AS IT MOVES
SOUTHEAST ACROSS PANHANDLE THROUGH SUN. THE CURRENT FORECAST
SUPPORTS THIS SOLUTION WITH LITTLE CHANGE NEEDED.

AS THE LOW AND FRONT MOVE INTO THE GULF...GALES WILL SPREAD INTO
THE NORTHERN AND EASTERN GULF FOR FRI NIGHT AND EARLY SAT. WINDS
WILL INCREASE TO AT LEAST SMALL CRAFT ON THE INNER CHANNELS ON
SAT. WINDY CONDITIONS WILL DEVELOP ALONG THE COAST AND INNER
CHANNELS WITH WIND ADVISORY GUSTS POSSIBLE ON SAT. MODERATE TO
HEAVY RAIN AT TIMES CAN BE EXPECTED WITH THE FRONT AS IT TAPS
INTO SOME SUBTROPICAL MOISTURE. SHOWERS WILL PREVAIL BEHIND THE
FRONT WITH GOOD CAA BUT WILL NEED TO WATCH FOR A POSSIBLE SECOND
WRAP BRINGING STEADY PRECIP AND WINDY CONDITIONS SOMETIME LATE
SAT NIGHT AND SUN.

A RIDGE BUILDS UP BEHIND THIS SYSTEM OVER THE CENTRAL AND EASTERN
GULF MON AND TUE LEADING TO DIMINISHING POPS AND POSSIBLE
SIGNIFICANT BREAKS IN CLOUD COVER. NEXT SYSTEM MOVES ACROSS THE
GULF WED AND THU.

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

TA/TAR