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FXAK67 PAJK 272359
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
359 PM AKDT FRI MAR 27 2015

.SHORT TERM...SHORT WAVE TROUGH PRIMARILY IMPACTING THE NORTHEAST
GULF COAST AND NORTHERN PANHANDLE DURING THE DAY WILL BE MOVING
ONSHORE THIS EVENING. AS A RESULT, SHOWERS WILL TAPER OFF
OVERNIGHT AND END BY MORNING AS WARM AIR ADVECTION IN ADVANCE OF
THE NEXT WEATHER FRONT MOVES IN AND STABILIZES THE ATMOSPHERE.
ACROSS THE SOUTHERN PANHANDLE THERE WAS SOME PATCHY FOG FRIDAY
MORNING AND LOW CLOUDS WHEN IT LIFTED. SUNSHINE BURNED MUCH OF IT
AWAY FOR A NICE DAY WITH AN ISOLATED SHOWER OR TWO OVER THE HIGHER
TERRAIN.

RAIN SHOULD SHUT OFF OVER NEARLY ALL OF THE PANHANDLE OVER NIGHT
WITH SOME MORE PARTIAL CLEARING EXPECTED ACROSS THE SOUTHERN
PANHANDLE TO THE POINT WHERE I HAVE BROUGHT PATCHY FOG BACK INTO
THE FORECAST FOR LATE TONIGHT AND EARLY SATURDAY TIME FRAME.

I CREATED A SHARP GRADIENT IN THE POP FIELD TO DENOTE AN ABRUPT
START TO PRECIPITATION ASSOCIATED WITH THE INCOMING WEATHER
FRONT. THIS RESULTED IN THE USE OF THE PHRASE "RAIN DEVELOPING" IN
THE TEXT.

WIND-WISE, GALES FOR THE MARINE ZONES WILL BE SPREADING IN FROM
THE WEST...WITH MOST OF THE SOUTHERN INNER CHANNELS GETTING UP TO
SMALL CRAFT LEVELS. EXPOSED CAPES OVER SOUTHERN BARANOF
ISLAND...PRINCE OF WALES ISLAND AND THE SOUTHERN INNER CHANNELS
WILL BE LOCALLY GUSTY SO HAVE GONE WITH GUSTS TO 35 BUT THIS COULD
EASILY BE SUFFICIENT FOR A STRONG WIND HEADLINE IF THE SYSTEM IS A
LITTLE STRONGER THAN EXPECTED.

.LONG TERM...MODEL AGREEMENT DETERIORATES EARLY ON IN THE EXTENDED
RAGE FORECAST PERIOD. AT ISSUE IS THE DIFFERENT TRACK AND
INTENSITY OF A LOW THAT DEVELOPS SOUTH OF THE GULF ON SUNDAY. MODEL
SPREAD HAS THIS LOW ANYWHERE FROM SOUTH OF HAIDA GWAII TO NEAR
CAPE DECISION AND STILL SOUTH OF THE GULF BY LATE MONDAY MORNING.
ALL ARE DEVELOPING THIS LOW IN A LOGICAL FASHION CONSIDERING THEIR
RESPECTIVE DEPICTIONS OF THE JET STREAM STRENGTH AND LOCATION. RUN
TO RUN CONSISTENCY HAS BEEN POOR AS WELL. THE MORNING GEM TRACKED
A VERY DEEP LOW ALONG THE OUTER COAST WITH SOLID GALES FOR THE
COASTAL MARINE ZONES AND STRONG WINDS FOR THE OUTER COAST.
AFTERNOON GEM RUN BACKED OFF ON THE INTENSITY AND PROXIMITY TO THE
COAST. MORNING AND AFTERNOON ECMWF TRACKED THE FEATURE OVER MISTY
FJORDS AND RAPIDLY WEAKENED THE SYSTEM OVER LAND. GFS AND NAM WERE
WEAKER THAN EITHER GEM RUN, BUT OFFERED A TRACK SUCH THAT, OF
THESE 4 MODELS, ECMWF WAS A CLEAR OUTLIER IN TERMS OF TRACK. OPTED
TO BLEND GFS AND NAM FOR TRACK WITH A LITTLE GEM TO DEEPEN THE LOW
AND FEEL THIS SOLUTION IS A GOOD MIDDLE GROUND IN TERMS OF
POTENTIAL IMPACT. RESULTING WIND FIELD PRODUCES A MARGINAL STRONG
WIND EVENT LATE SATURDAY NIGHT INTO SUNDAY. FORECAST CONFIDENCE IN
THIS LOW IS BELOW AVERAGE DUE TO MODEL SPREAD AND RUN TO RUN
CONSISTENCY PROBLEMS.

ANOTHER ITEM OF NOTE IS THE POTENTIAL FOR A SIGNIFICANT SNOW EVENT
ALONG THE HAINES HIGHWAY SATURDAY NIGHT INTO SUNDAY. 18 HOUR SNOW
TOTALS FOR NEAR THE BORDER ARE CURRENTLY 6 INCHES OF SNOW.
FORECAST CONFIDENCE IN THIS ASPECT OF THE FORECAST IS DECIDEDLY
BELOW AVERAGE AT THIS TIME.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...GALE WARNING FOR PKZ041>043-051-052.
         SMALL CRAFT ADVISORY FOR PKZ011-012-021-022-033>036.
         SMALL CRAFT ADVISORY DUE TO SEAS FOR PKZ053.

&&

$$

BEZENEK/FRITSCH

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