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FXAK67 PAJK 281250
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
450 AM AKDT THU AUG 28 2014

.SHORT TERM...RADIATION FOG HAS BEEN A FACTOR IN A COUPLE SOUTHERN AREAS
TONIGHT...MOST PROBLEMATIC AT PETERSBURG AND OCCASIONAL AT AJN.
LIGHT RAIN HAS DEVELOPED AT YAKUTAT TONIGHT IN RESPONSE TO NEW
STORM CENTER ENTERING THE GULF. LOW CENTER OVER WESTERN GULF IS
MOVING SLOWLY EASTWARD AND NICE OCCLUSION SHOULD FORM TODAY OVER
THE EASTERN GULF. LOW IS AIDED BY DYNAMIC JET ALOFT ROUNDING THE
BASE OF THE TROUGH. THIS SETUP HAS RESULTED IN SCA FOR MARINE
ZONES ADJACENT TO THE COAST AS WELL AS NORTHERN LYNN, SUMNER AND
CLARENCE AS THE LOW PROGRESSES EASTWARD. WE WENT WITH 15-20KT
WINDS IN CROSS SOUND AND YAKUTAT BAY BUT THESE WILL NEED TO BE
MONITORED. WE STRUGGLED WITH N VS S WINDS IN SOME OF THE INNER
CHANNELS AND ENDED UP GOING MOSTLY WITH S. ISOLATED CONVECTION
LIKELY TO BE FACTOR TODAY OFFSHORE AND A POSSIBILITY PROGRESSING
ACROSS SOUTHERN PORTIONS TO THE SOUTHERN PANHANDLE BY EARLY
FRIDAY.

MODEL FIELDS WERE IN GENERAL AGREEMENT WITH THE EXCEPTION OF THE
00Z NAM WHICH SEEMED TO UNDERDO SPINUP OF THE GULF LOW TODAY. WE
ELECTED TO GO WITH MINOR CHANGES IN WINDS WITH A COMBO OF GFS AND
ECMWF LOW-LEVEL FIELDS. MOSTLY LIGHT RAIN AMOUNTS FOR THE NORTHERN
PANHANDLE THROUGH FRIDAY MORNING. THREAT FOR PROBLEMATIC RAIN
AMOUNTS THUS SEEMS TO BE LOW ALTHOUGH CANNOT RULE OUT BRIEF HEAVY
RAIN LATE TONIGHT AND FRIDAY IN SOME OF THE SOUTHERN AREAS.
FORECAST CONFIDENCE IS AVERAGE FOR THIS PERIOD.

.LONG TERM...MODELS REMAIN IN GENERAL AGREEMENT WITH A COUPLE OF
UPPER LEVEL SHORTWAVE TROUGHS PASS OVER THE GULF AND ACROSS THE
NORTHERN PANHANDLE THROUGH LATE SATURDAY. THE ASSOCIATED SURFACE
LOW WITH THE FIRST UPPER LEVEL TROUGH IN THE NORTHEASTERN GULF
WILL CONTINUE TO MOVE INTO THE EASTERN GULF...THEN WEAKEN AND
DISSIPATE BY LATE FRIDAY NIGHT AS ANOTHER SURFACE LOW MOVES INTO
THE EASTERN GULF WITH THE SECOND UPPER LEVEL TROUGH. COOLER
TEMPERATURES ALOFT WITH THE SHORTWAVE TROUGH WILL INCREASE
INSTABILITY ACROSS THE SOUTHERN OUTER WATERS AND SOUTHERN
PANHANDLE ON FRIDAY. MAINTAINED POTENTIAL THUNDERSTORM WORDING FOR
FRIDAY. SMALL CRAFT LEVEL WINDS AND SEAS WILL REMAIN ACROSS THE
CENTRAL OUTSIDE WATERS ON FRIDAY. REFRESHED THE INHERITED FORECAST
PACKAGE WITH THE ECMWF THROUGH SATURDAY NIGHT DUE TO ITS GOOD
INITIALIZATION AND CONSISTENCY. OVERALL CHANGES WERE MINOR AND
FORECAST CONFIDENCE SLIGHTLY ABOVE AVERAGE.

STAYED WITH THE WPC ENSEMBLE SOLUTIONS FROM SATURDAY ONWARD. THE
UPPER LEVEL SHORTWAVE TROUGH WILL WEAKEN AND DRIFT EAST ACROSS THE
PANHANDLE...FOLLOWED BY NEAR ZONAL FLOW THROUGH THE WEEKEND. NO
SIGNIFICANT WINDS/SEAS ARE EXPECTED WITH DECREASING POPS. WITH
INCREASING UNCERTAINTY...STILL EXPECT ANOTHER LOW MOVES ACROSS THE
GULF AND ONSHORE OVER THE PANHANDLE ON LABOR DAY HOLIDAY THROUGH
THE MID WEEK. MAINTAINED GENERALLY WET WEATHER WITH LIKELY LEVEL
POPS OVER THE MAIN PANHANDLE THROUGH EARLY TUESDAY. POPS WILL
GRADUALLY DECREASE SOUTHEAST THROUGH LATE WEDNESDAY NIGHT.
FORECAST CONFIDENCE FALLS BELOW AVERAGE.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...SMALL CRAFT ADVISORY FOR PKZ012-035-036-041>043-051-052.

&&

$$

WESLEY/BEZENEK/AHN

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