Storm Warning 12, NWS Juneau, AK

000 
FZAK67 PAJK 101249
OFFAJK

OFFSHORE FORECAST FOR GULF OF ALASKA EAST OF 144 WEST
NATIONAL WEATHER SERVICE JUNEAU AK
400 AM AST SAT MAR 10 2007 

WIND FORECASTS REFLECT THE PREDOMINANT SPEED AND DIRECTION
EXPECTED. SEA FORECASTS REPRESENT THE AVERAGE OF THE HIGHEST
ONE-THIRD OF THE COMBINED WINDWAVE AND SWELL HEIGHT.

PKZ398-110100-
.SYNOPSIS FOR GULF OF ALASKA NORTH OF 55 NORTH AND EAST OF
144 WEST...
A LARGE AREA OF LOW PRESSURE WILL REMAIN OVER THE NORTHERN GULF
INTO THE FIRST PART OF NEXT WEEK. A WEAK LOW WILL MOVE OVER THE
NORTHERN INNER CHANNELS BY MONDAY MORNING. OUTLOOK. UNSETTLED
WEATHER WILL CONTINUE OVER THE GULF OF ALASKA AND PANHANDLE
THROUGHOUT THE UPCOMING WEEK. 

$$

PKZ310-110100-
GULF OF ALASKA NORTH OF 55 DEGREES NORTH AND EAST OF 144 DEGREES
WEST-
400 AM AST SAT MAR 10 2007 

.TODAY...S WIND 15 TO 20 KT. SEAS 11 TO 15 FT. SW SWELL. SNOW
AND RAIN SHOWERS. 
.TONIGHT...SW WIND 15 TO 25 KT. SEAS 9 FT. SW SWELL. SNOW
SHOWERS. 
.SUN...SW WIND 15 TO 25 KT. SEAS 9 FT. SW SWELL. SNOW SHOWERS.
.SUN NIGHT...SW WIND 15 TO 25 KT. SEAS 12 FT. W SWELL. 
.MON...W WIND 15 TO 20 KT. SEAS 11 FT. SW SWELL. 
.TUE...W WIND 15 TO 25 KT. SEAS 12 FT. 
.WED...W WIND 15 TO 20 KT. SEAS 12 FT.  

$$

SOUTHEAST ALASKA FORECAST DISCUSSION
1100 AM AST FRI MAR 9 2007

.SYNOPSIS...
.SHORT RANGE...SATELLITE IMAGERY REVEALS THAT THE GULF AND
PANHANDLE ARE STILL UNDER PRONOUNCED CONVECTIVE ENVIRONMENT WITH
LIGHTNING BEING DETECTED EAST OF ANNETTE ALONG THE COAST EARLIER
THIS MORNING. HEAVY SHOWERS CONTINUE TO AFFECT THE ENTIRE
PANHANDLE WITH VERY GUSTY WINDS ACCOMPANYING THESE SHOWERS. SOME
GUSTS THIS MORNING IN YAKUTAT...SKAGWAY...METLAKATLA...HAVE BEEN
AT OR ABOVE ADVISORY CRITERIA BUT ARE OF SUCH SHORT DURATION THAT
WIND ADVISORIES NOT CONSIDERED APPROPRIATE. BIG FORECAST
CHALLENGE TODAY IS THE TIMING OF THE ARRIVAL OF THE STRATIFORM
SNOW...HOW MUCH THE PANHANDLE WILL RECEIVE...AND WHERE THE RAIN
SNOW LINE WILL BE. CURRENT WATCH RUNS FROM NOON TO MIDNIGHT AND
AM THINKING OF EXPANDING IT FROM 9AM SATURDAY TO 6AM SUNDAY. THIS
DUE TO GFS PRESENTING A SLIGHTLY FASTER SOLUTION THAN UKMET OR
NAM WHICH DELAY FRONTAL PASSAGE THROUGH THE NORTHERN PANHANDLE
UNTIL SUNDAY MORNING. AM EXPECTING STRATIFORM PRECIPITATION TO
BEGIN LATE TONIGHT...SPREADING FROM SOUTH TO NORTH ACROSS THE
PANHANDLE. BASED ON CURRENT DATA BELIEVE THE RAIN SNOW LINE WILL
RUN FROM SOUTHERN BARANOF ISLAND THROUGH VICINITY WRANGELL AND
MAKE ITS FARTHEST NORTHERLY ADVANCE BY SATURDAY AFTERNOON. FULL
EXPECT TO SEE WIDESPREAD AREAS OF 6 INCH SNOWFALL IN 12 HOURS.
LIMITING FACTOR WILL BE AMOUNT OF PRECIPITABLE WATER AS THIS
DEVELOPING SYSTEM IS NOT TAPPING THE MOIST TROPICAL AIRMASS TOO
EFFECTIVELY. COLD AIR CURRENTLY IN PLACE OVER THE PANHANDLE WILL
PROVIDE THE LIFT AS WELL AS DEPRESS THE SNOW LEVEL FARTHER SOUTH
THAN BENCHMARK GUIDANCE WOULD SUGGEST. ONCE THE COLD FRONT DOES
MOVE THROUGH THE PANHANDLE...WILL RESUME HEAVY SHOWER ACTIVITY
WITH STRONG GUSTY WINDS THIS WEEKEND.

.LONG RANGE...THE FORECAST MODELS THIS MORNING ARE IN FAIR
AGREEMENT. THERE IS STILL SOME DIFFERENCES WITH THE SIGNIFICANT
WEATHER SYSTEM FOR LATE SAT AFTERNOON THROUGH THE EARLY SUNDAY
MORNING. THE MAIN DIFFERENCE IS AT THE UPPER LEVELS...WHEN THE
UPPER TROF LIFTS OVER THE NORTHERN AREAS AND INTO THE YUKON. ALL
THE MODELS HAVE A DEVELOPING WAVE LIFTING OVER THE CENTRAL
PANHANDLE SAT NIGHT BUT THE TIMING ON WHEN THE COLD FRONT PUSHES
THROUGH IS THE MILLION DOLLAR QUESTION.

THE GFS IS THE ODD MODEL OUT AS IT LIFTS THE UPPER TROF INTO
CANADA BY 12Z SUN BUT THE NAM...ECMWF AND THE UKMET MOVE THIS
FEATURE SLOWER THROUGH THE NORTHERN AREAS AND HAVE IT INTO THE
YUKON BY SUN MORNING. THE GFS HAS BEEN SLOWING THIS SYSTEM DOWN
THE PAST COUPLE OF DAYS SO WILL GO WITH THE SLOWER SOLUTION AND
WITH THAT WILL ISSUE A HEAVY SNOW WARNING FOR THE AREAS IN THE
WATCH AREA ATTM.

THE OVER RUNNING PRECIP WILL ALL READY HAVE BEGUN BY SAT EVENING
WITH WARM AIR PUSHING NORTH ALOFT. IT LOOKS LIKE THE BEST
DYNAMICS WILL MOVE OVER THE AREA OVER NIGHT AS A STRONG SHORTWAVE
WILL LIFT OVER THE AREA BY 06Z JUST OFFSHORE WITH STRONG PVA. THE
SHORTWAVE WILL PRODUCE HEAVY SNOW OVER THE NORTHERN HALF THROUGH
THE NIGHT. AS THE COLD FRONT LIFTS OVER THE AREA LATE SAT
NIGHT/EARLY SUN MORNING AND THE PRECIP RATES GO DOWN BUT SHOWERS
WILL CONTINUE THROUGH SUN. AMOUNTS WILL BE FROM 6 TO 8 INCHES
WITH LOCALLY HIGHER AMOUNTS OVER THE WARN AREA FROM SAT AFTERNOON
THROUGH EARLY SUN MORNING. THE WARM AIR ASSOCIATED WITH THIS
SYSTEM WILL KEEP THE SOUTHERN THIRD AND THE COASTAL AREAS RAIN
THROUGH SAT NIGHT BUT AS THE COLD FRONT LIFTS THOUGH EVERYONE
WILL BE IN SNOW SHOWERS. THINK THE CENTRAL INNER CHANNELS WILL
SEE A MIX OF RAIN AND SNOW BUT NEAR PAPG THEY WILL REMAIN ALL
SNOW AND COULD SEE FROM 3 TO 7 INCHES OVER SAT NIGHT...SO WILL
ISSUE A SNOW ADVISORY WITH THE 4 PM PACKAGE FOR SAT NIGHT.

FOR SUNDAY AND THE REST OF THE WEEK. THE VERTICALLY STACKED
SURFACE LOW PRESSURE IN THE NORTHERN GULF WILL PERSIST THROUGH
MID WEEK. THIS LOW ACCOMPANIED WITH THE UPPER LEVEL TROF OVER THE
GULF WILL KEEP SNOW SHOWERS OVER THE ENTIRE FORECAST THROUGH
TUESDAY NIGHT. AMOUNTS WILL VARY AND DEPENDING ON WHERE THE
STRONGER SHOWERS MOVE OVER BUT 1 TO 4 INCHES WOULD BE THE RANGE
EACH DAY THROUGH MONDAY NIGHT.

IT LOOKS LIKE THERE WILL BE A CHANGE IN THE UPPER LEVEL PATTERN
AFTER MID WEEK. THE UPPER LEVEL LOW OVER THE ARCTIC COAST WILL
SLIDE SOUTHWEST OVER THE INTERIOR OF THE STATE AND SET UP SHOP
OVER SOUTHWEST AK. THIS WILL CUT OFF THE COLD AIR FROM THE POLE
INTO THE GULF AND SET UP A LONG FETCH OF SOUTHWEST FLOW FROM THE
NORTH PACIFIC WITH A UPPER RIDGE BUILD OVER THE WESTERN CONUS. SO
WITH THAT SAID THERE WILL BE A SIGNIFICANT WARMING FROM THE PAST
COUPLE OF WEEKS BY THURSDAY INTO FRIDAY. POTENTIALLY A LOW
PRESSURE SYSTEM MOVING INTO THE SOUTHEAST GULF BY THURSDAY
MORNING.

.AJK...WATCHES/WARNINGS/ADVISORIES
PUBLIC...WSW SATURDAY AFTERNOON-SATURDAY NIGHT 19>22-24-25
         SNOW ADVY PKZ26 SAT NIGHT
MARINE...GALE 52 -- SMCR ELSEWHERE EXCEPT PZK032