Gale Warning 227, NWS Juneau, AK

SOUTHEAST ALASKA FORECAST DISCUSSION
1145 AM ADT THU SEP 20 2007

.SYNOPSIS...
.SHORT RANGE...WEAK RIDGING IN THE EASTERN GULF TODAY IS MAKING
FOR ONSHORE FLOW. CEILINGS AND VISIBILITITES STAYING MOSTLY IN
MVFR RANGE IN MOIST AIR MASS. HIGH BUILDS INLAND THUR AFTN MORE
STABILIZING TREND. SCA WINDS LYNN CANAL THU MORNING WILL DIMINISH
BELOW 20KTS THIS AFTN AND BE LIGHT THIS EVE. MAIN FCST ISSUE IN
SHORT RANGE IS RAPIDLY DEEPENING LOW FORECAST TO CRANK UP WHILE
MOVING THROUGH THE SOUTHERN OFFSHORE WATERS ZONE TONIGHT.
FORECASTS ARE WELL COORDINATED WITH NEIGHBORS IN ANCHORAGE AND
VANCOUVER.

STILL SEEN AS BAROCLINIC LEAF IN SATELLITE IMAGERY... CENTRAL
PRESSURE NEAR THE DEVELOPING WAVE SOUTH OF KODIAK ISLAND IS
AROUND 1012 MB. SATELLITE IMAGERY SHOWS CHARACTERISTICS OF
DEVELOPMENT/DEEPENING AND A NARROW TAP INTO TROPICAL MOISTURE
PLUME ALONG DATELINE. UNFORTUNATE GAP THIS MORNING IN COVERAGE OF
SSMI WINDS OVER AREA OF INTEREST. MODEL FORECASTS DEEPEN THIS LOW
QUICKLY TO BETWEEN 985MB /CANADIAN/ TO 995MB /NAM/ TONIGHT IN THE
SE OFF WATERS ZONE. WILL FOLLOW CURRENT GRIDS AND CURRENT
ENVIRONMENT CANADA THINKING OF TAKING LOW TO CRAIG THEN WRANGELL
LATE THUR NIGHT AND LEANING TOWARD DEEPER SOLUTIONS. DEEPENED
CENTRAL PRESSURE OF APPRCHG LOW A BIT TONIGHT IN THE GRIDS AND IT
GENERATED WINDS CLOSE TO WHAT IS ALREADY FCST. RESULT IS SOLID
GALES OVER SOUTHERN MARINE ZONES INCLUDING CLARENCE STRAIT EARLY
FRIDAY MORNING. WIND ADVISORIES ALREADY ISSUED FOR LAND ZONES
SOUTH OF A PORT ALEXANDER TO HYDER LINE. RAIN WILL BE WIDESPREAD
TONIGHT BUT END FROM NORTH LATE TONIGHT ANY BY MID DAY CENTRAL
PANHANDLE. RAIN HEAVY AT TIMES WILL PERSIST INTO FRI AFTERNOON
OVER SRN SE AK MTNS...ESPECIALLY ZONE 29. BROAD CYCLONIC FLOW
OVER ERN GULF/SE AK LATER FRI AND FRI NIGHT KEEPS A MOIST AIR
FLOW INTO PANHANDLE. COOLING ALOFT POST FRONTAL ALSO ADDS TO
INSTABILITY STARTING FRI AFTERNOON AND LOWERS FREEZING LEVELS TO
4000-4500 FT BY LATE FRI.

.LONG RANGE...WINDS OVER THE SOUTHERN OFF SHORE AND COASTAL AREAS
SUBSIDING FRIDAY EVENING AS THE LOW MOVES FURTHER INTO WESTERN
CANADA.

MID RANGE MODELS STILL HAVE FAIR CONCENSUS ON NEXT INCOMING
SYSTEM FOR THE WEEKEND...WHICH APPEARS TO BE A TOUCH SLOWER THAN
THE CURRENT FORECAST. FORECAST MODELS SWEEP THIS SYSTEM ACROSS
THE GULF SATURDAY NIGHT AND SUNDAY AND ONSHORE JUST SOUTH OF THE
SITKA AREA SUNDAY NIGHT. EXPECT THE NEXT BATCH OF RAIN AND WIND
SUNDAY ACROSS THE PANHANDLE AREA. HAVE NUDGED THE CURRENT
FORECAST GRIDS A LITTLE CLOSER TO THE GFS40. LOOKS AS IF GALE
FORCE WINDS WITH THE SYSTEM SHOULD MOVE INTO THE COASTAL WATERS
AND THE OFF SHORE AREAS.

IN THE LONGER RANGE WILL NOT BE MAKING MUCH IF ANY CHANGES AS THE
CURRENT FORECAST IS CLOSE TO WHAT THE LONG RANGE MODELS ARE
SUGGESTING.  AS A RESULT WILL NOT TRY AND NIT-PICK ANY MINOR
DETAILS AT THAT RANGE.

.AJK...WATCHES/WARNINGS/ADVISORIES
PUBLIC...WIND ADVISORY TONIGHT SOUTHERN ZONE 23 AND ZONES
            27-28-29
MARINE...SCA ENDING THIS AFTN LYNN CANAL.
         GALES TONIGHT AND EARLY FRI SOUTHERN OFFSHORE...
            PKZ041-42 AND CLARENCE STR.
         SCA TONIGHT FREDERICK.. SUMNER.. SO CHATHAM.. AND OUTER
            COAST N OF CAPE EDGECUMBE

TA - BMB