Area Forecast Discussion
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FXAK67 PAJK 130100
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
400 PM AKST FRI FEB 12 2016

.SHORT TERM...THE LATEST SATELLITE IMAGERY SHOWS A LOW DISSIPATING
OVER THE NORTHERN GULF. THE ASSOCIATED WEATHER FRONT IS PRODUCING
STRONG WIND GUSTS NEAR YAKUTAT AND HEAVY RAIN ALONG WITH SOME
ISOLATED THUNDERSTORMS OVER THE NORTHERN GULF. THESE CONDITIONS
WILL RELAX THROUGH THE EVENING AS THE UPPER LEVEL SUPPORT LIFTS
INTO CANADA. THE REST OF THE FORECAST AREA IS SEEING SCATTERED
SHOWERS WITH SOME GUSTY WINDS WITH THE SOUTHERN HALF SEEING A NICE
DAY WITH SUNNY BREAKS. THERE IS SOME SOUTH WINDS OVER THE INNER
CHANNELS RANGING FROM 15 TO 20 KT BUT THESE WINDS WILL DIMINISH
OVERNIGHT AS THE WEAK SURFACE RIDGE OVER THE INNER CHANNELS DRIFTS
INTO CANADA.

THERE WILL BE ANOTHER SURFACE TROF THAT WILL MOVE OVER THE
SOUTHERN AREAS THIS EVENING AND THEN LIFT NORTH BY SATURDAY
MORNING. THE NORTHERN AREAS WILL SEE THE SHOWERS IN THE MORNING
DECREASE BY THE AFTERNOON AS THE UPPER TROF LIFTS NORTH. THE
SOUTHERN AREAS WILL SEE A BREAK IN THE MORNING BUT A WARM FRONT
WILL LIFT OUT OF THE NORTH PACIFIC AND MOVE INTO THE EASTERN GULF.

WINDS OVER THE INNER CHANNELS NORTH OF FREDERICK SOUND WILL SEE
THE WINDS INCREASE FROM THE NORTH AS THE RIDGE MOVES INTO CANADA
AND THE TROF MOVES OVER THE SOUTHERN AREAS. THE WILL INCREASE SOME
ON SATURDAY BUT FOR THE MOST PART THEY WILL RANGE FROM 10 TO 20
KT. THE STRONGEST WINDS WILL BE OVER THE CLARENCE STRAIT WITH
SMALL CRAFT WINDS DEVELOPING LATE TONIGHT AND PERSISTING THROUGH
SATURDAY.

OVERALL THERE IS ABOUT AVERAGE FORECASTER CONFIDENCE AND A BLEND
OF THE NAM AND GEM WERE USED FOR ANY CHANGES IN THE SHORT TERM
PERIOD.

.LONG TERM...THE STRONG SOUTHWEST FLOW PATTERN WITH A 140 TO 160
KT JET IN IT CONTINUE TO AIM AT THE NORTHERN BRITISH COLUMBIA
COAST TO DIXON ENTRANCE THROUGH MONDAY. A SHORT WAVE EARLY NEXT
WEEK LOOKS TO DEEPEN THE TROUGH AS IT DIGS SOUTHWARD SHARPENING
THE LONG WAVE TROUGH. MEAN WHILE FROM EARLY NEXT WEEK TO END OF
THE WEEK A STRONGER ZONAL FLOW PATTERN WITH A JET STREAM OVER 170
KT WILL START TO MOVE ACROSS THE NORTHWEST AND NORTHERN PACIFIC.
AS A RESULT ALOFT OF THE SYSTEMS WILL BE MOVING A QUICK CLIP
THROUGH THE REGION.

AS A RESULT LOOK FOR COOLER TEMPERATURES OVER THE NORTHERN
PANHANDLE AS THE WARMER AIR IS NOT EXPECTED TO DRIVE NORTH TO THE
NORTHERN PANHANDLE THE NEXT FEW DAYS. SO SOUTHEAST ALASKA RAIN
WITH THE FRONTAL BANDS AND THEN BRIEF SHOWER LIKE PATTERN BEFORE
A BREAK DEVELOPS AHEAD OF THE NEXT WAVE. WITH THE COOLER
TEMPERATURES IN THE NORTH...SOME SNOW MAY FALL.

MOST OF THE ENERGY FOR THE WEATHER SYSTEMS TO IMPACT THE AREA
(SUNDAY MONDAY AND LATE TUESDAY NIGHT) WILL IMPACT BRITISH
COLUMBIA. THE SOUTHERN PANHANDLE WILL RECEIVE BETTER RAINFALLS
THAN THE NORTHERN PANHANDLE ON THE SUNDAY AND MONDAY
SYSTEMS...WEAKER FEATURES ASSOCIATED WITH THEM WILL SPREAD ACROSS
THE NORTHERN GULF FOR PERIODS OF LIGHT RAIN (LESS THAN QUARTER
INCH).

MODELS ARE INDICATING TIMING AND POSITION DIFFERENCES FOR THE
EARLY PART OF NEXT WEEK SO CONFIDENCE IS AVERAGE AT BEST THUS
STAYED MORE IN LINE WITH THE WPC LONG RANGE GUIDANCE THERE WITH
MINIMAL CHANGES TO THE FORECAST PACKAGE.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...STRONG WIND UNTIL 6 PM AKST THIS EVENING FOR AKZ017.
MARINE...GALE WARNING FOR PKZ043-051-052.
     SMALL CRAFT ADVISORY FOR PKZ022-033-034-036-041-042-053.
&&

$$

ABJ/BEZENEK

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