FXAK67 PAJK 112326
AFDAJK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
226 PM AKST THU MAR 11 2010

.SHORT TERM...THE LATEST SATELLITE LOOP SHOWS A STRONG LOW JUST
WEST OF SITKA...SLOWLY MOVING NORTHWARD. A WEAKENING FRONT WRAPS
AROUND THE LOW AND ACROSS THE PANHANDLE WITH STRONG WINDS OVER
THE SOUTHERN AREAS AND RAIN. RAIN MIXING WITH SNOW CONTINUES
ACROSS THE CENTRAL PANHANDLE WITH MODERATE SNOWFALL ON OR AROUND
ELFIN COVE AND PELICAN AREAS. THE TRAILING EDGE OF THE FRONT
PASSING OVER THE SOUTHERN AREAS DECREASES GUSTY WINDS AND ALLOWS
THE WIND ADVISORY EXPIRED. A TROUGH FORMING JUST BEHIND THE
FRONTAL BOUNDARY WILL MAINTAIN NEAR ADVISORY LEVEL GUSTS
MOMENTARILY BUT THE OBSERVATIONS ACROSS THE DIXON ENTRANCE AND
CHARLOTTES INDICATE A QUICK DROP OF WIND SPEED. AS THE FRONT
CONTINUES DRIFTS NORTHWARD...THE ADVISORY LEVEL WIND GUSTS WILL
CONTINUE ACROSS THE SOUTH CENTRAL PANHANDLE THROUGH EARLY THIS
EVENING.

MODELS ARE IN FAIR AGREEMENT WITH THE LOW W OF SITKA SLOWLY
WEAKENING AS IT MOVES OVER GLACIER BAY THIS EVENING. THE LOW WILL
CONTINUE TO WEAKEN OVER THE SOUTHWESTERN YUKON THROUGH LATE
TONIGHT. THE ASSOCIATED FRONT WILL CONTINUE TO DRIFT
NORTHEASTWARD ACROSS SOUTHEAST ALASKA THROUGH LATE TONIGHT. A
WEAKENING SECOND WRAP BEHIND THE TRAILING EDGE OF THE FRONT WILL
MAINTAIN BREEZY CONDITION ACROSS THE FORECAST DOMAIN THROUGH
EARLY TONIGHT. MODERATE SNOW IN ELFIN COVE HAS CHANGED TO MIXING
WITH RAIN AT THIS TIME...BUT WILL KEEP THE WINTER WEATHER
ADVISORY THROUGH TONIGHT AS COLDER AIR MOVING INTO THE AREA
BEHIND THE LOW. AS THE LOW MOVES OVER GLACIER BAY...WINDS WILL
PICK UP TO ADVISORY LEVEL GUSTS ACROSS THE NORTHERN LYNN CANAL.
WILL KEEP THE WIND ADVISORY FOR SKAGWAY AS PREVIOUSLY ISSUED FOR
TONIGHT.

.LONG TERM...THE LONG TERM MODELS CONTINUE TO BE IN GOOD AGREEMENT
ALONG WITH RUN TO RUN CONSISTENCY THROUGH THE WEEKEND BUT THEN
THEY DIFFER THROUGH NEXT WEEK WITH BELOW AVERAGE FORECAST
CONFIDENCE. THERE WAS MANY CHANGES DONE FROM THE PREVIOUS FORECAST
AND CONTINUE TO USE THE EC THROUGH THE MID RANGE THEN USED HPC
GUIDANCE FROM MONDAY THROUGH NEXT THURSDAY.

AT THE START OF THE LONG TERM A UPPER SHORTWAVE TROF WILL BE
LIFTING OVER THE PANHANDLE. ASSOCIATED WITH THE TROF IS SOME
COLDER AIR SO THE SHOWERS WILL BE IN THE FROZEN FORM WITH
ACCUMULATIONS OF 1 TO 3 INCHES. THE SHOWERS WILL DIMINISH THROUGH
EARLY SAT MORNING AS ANOTHER STRONG FRONT WILL MOVE INTO THE GULF
BY SAT MORNING. THE FRONT WILL MOVE SLOW OVER THE PANHANDLE AND
NOT BE EAST OF THE AREA UNTIL SUN NIGHT. THIS FRONT WILL SPREAD
MAX GALES ACROSS THE EASTERN GULF ALONG WITH WIND ADVY GUSTS OVER
THE COASTAL AREAS OF THE PANHANDLE. THE P TYPE WITH THE FRONT WILL
BE TRICKY OVER THE CENTRAL INNER CHANNELS. MIXED PRECIP WILL MOVE
OVER THE COASTAL AREAS AND SOUTHERN AREAS THROUGH SAT AND SPREAD
INLAND IN THE LATE AFTERNOON/EARLY EVENING. THERE IS A CHANCE OF
SIGNIFICANT WINTER WX FOR THE FAR NORTHERN INNER CHANNELS WITH A
MIX OF RAIN AND SNOW OVER THE NORTH CENTRAL AREAS. AMOUNTS OVER
THE NORTH CENTRAL WILL BE HARD TO PIN POINT AS IT WILL DEPEND ON
THE TIME IT CHANGES TO ALL RAIN WITH WAA. THE FRONT WILL INCREASE THE
WINDS OVER THE INNER CHANNELS TO BE WINDY WITH GALES OVER E/W
CHANNELS AND SMALL CRAFT OVER N/S CHANNELS. THE PRECIP WILL BE
HEAVY AT TIMES ON SUN AS THERE WILL STRONG UPPER LEVEL DYNAMICS
ALONG WITH OROGRAPHIC LIFTING.

INTO NEXT WEEK...THE MAIN UPPER LEVEL LOW ASSOCIATED WITH THE
FRONT OVER THE WEEKEND WILL REMAIN OVER THE CENTRAL GULF AND SWING
ENERGY OVER THE PANHANDLE. THE SHOWERS ASSOCIATED WITH THE ENERGY
WILL BE A MIX OF RAIN AND SNOW BUT ATTM THINK IT MAY BE MORE RAIN
THAN SNOW.

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...WIND ADVISORY UNTIL 6 PM AKST THIS EVENING FOR AKZ023-026.
WINTER WEATHER ADVISORY UNTIL 5 AM AKST FRIDAY FOR AKZ022.
WIND ADVISORY FROM 9 PM THIS EVENING TO 5 AM AKST FRIDAY FOR
AKZ018.
MARINE...STORM WARNING FOR PKZ036.
GALE WARNING FOR PKZ013-022-031-033>035-041>043-051.
SMALL CRAFT ADVISORY FOR PKZ011-012-021-032-052.

&&

$$

AHN/ABJ


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