Area Forecast Discussion - Southeastern
FXAK67 PAJK 312333
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
330 PM AKDT THU JUL 31 2014
.SHORT TERM...VERY STABLE WEATHER PATTERN WILL PERSIST OVER SE AK
DURING THE SHORT TERM PERIOD. UPPER LOW WILL REMAIN STATIONARY
OVER THE CNTRL/WRN GULF WHILE A BROAD AREA OF TROUGHING CONTINUES
FROM NRN AK INTO THE NW TERRITORIES OF CANADA. A MIDLEVEL COL WILL
RESIDE OVER SCNTRL AK BETWEEN THESE TWO FEATURES. AT THE
SURFACE...LOW PRESSURE WILL BE SITUATED BENEATH THE UPPER LOW OVER
THE GULF AND HIGH PRESSURE WILL EXTEND NNWWD ALONG THE OFFSHORE
WATERS OVER SE AND SCNTRL AK. SUBSIDENT LARGE-SCALE REGIME WILL
YIELD MAINLY CLEAR SKIES AND WARM AFTERNOON TEMPERATURES OVER THE
REGION THU AND FRI AFTERNOON...WITH HIGHS APPROACHING 70 DEGREES
DURING FRI. THIS WILL AID IN SEA BREEZE DEVELOPMENT FOR MANY LAND
AREAS...AS WELL AS A NWLY CHANNEL BREEZE OVER CROSS SOUND THAT MAY
REACH 25 KT. STRONG RADIATIONAL COOLING IS FORECAST TO OCCUR
TONIGHT. THIS WILL LEAD TO A STRENGTHENING NOCTURNAL INVERSION
OVER MUCH OF THE AREA FAVORING FOG DEVELOPMENT. THE ONE CAVEAT
WILL BE DRYING TAKING PLACE THIS AFTERNOON DUE TO ABUNDANT
SUNSHINE AND SURFACE HEATING. THIS RESULTS IN SOME UNCERTAINTY
REGARDING THE MAGNITUDE OF VISIBILITY REDUCTION OVERNIGHT.

MODEL GUIDANCE INITIALIZED VERY WELL THIS MORNING AND SHOWED
EXCELLENT AGREEMENT THROUGH 00Z SAT. INHERITED GRIDS WERE
SUPPORTED BY LATEST MODEL OUTPUT...THUS FEW CHANGES WERE MADE.
FORECAST CONFIDENCE IS HIGH...WITH THE EXCEPTION OF FOG
DEVELOPMENT TONIGHT.
.LONG TERM...MAIN FEATURE IS A PLANETARY SCALE LOW ANCHORED NEAR
50N 153W ON SAT MORNING. THIS HAS HAS ALLOWED A SHORT-LIVED UPPER
RIDGE OVER THE EASTERN GULF COAST. ALL GUIDANCE INDICATES THAT BY
SUN AFTERNOON THE UPPER LEVEL FLOW WILL BECOME SOUTH OVER OUR AREA.
THIS WILL EVENTUALLY BRING MOISTURE FIRST AS CLOUDS THEN RAIN.
TODAYS 31/12Z OPS MODELS ARE HESITANT ABOUT BRINGING A SLUG OF RAIN
EARLY ON SO THE FORECASTS REFLECT INCREASING CHANCES STARTING SUN
EVENING THEN LIKELY LATER IN THE WEEK. CONFIDENCE AGAIN HIGH ABOUT
THE PATTERN CHANGE BUT LOW AS TO EXACT TIMING OF PULSES. 

SATURDAY FORECASTS HAD SPECIAL ATTENTION DUE TO THE SUNSHINE.
ENHANCED SEA BREEZES AND RAISED MAX TEMPS SATURDAY AFTERNOON AND
EVENING. CLOUDS ON SUNDAY WILL MAKE IT A COOLER DAY SO WILL HAVE
LESS WIND THEN. DAYS 4 THROUGH 8 USED WPC GUIDANCE FOR BLEND OF
MODELS AND ENSEMBLES. UPPER LOW CONTINUES TO DOMINATE THE EASTERN
GULF INTO NEXT THU. 

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...SMALL CRAFT ADVISORY FOR PKZ012-022. 

&&

$$

GARNER/JC

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