Small Craft Advisory 151, NWS Juneau, AK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
1137 AM ADT FRI MAR 14 2008

.SHORT TERM...AN UPPER LEVEL TROUGH SWINGING THROUGH THE
PANHANDLE IS RESPONSIBLE FOR A SWATH OF RAIN AND SNOW LOCATED
ALONG AND SOUTH OF A SITKA TO JUNEAU LINE. THIS BAND OF LIGHT
PRECIPITATION IS SLIDING  EAST-SOUTHEASTWARD THIS MORNING WHILE
AN UPPER LEVEL RIDGE BUILDS IN BEHIND THE TROUGH.  SATELLITE
INDICATES CLEAR SKIES ACROSS THE NORTHERN GULF...INCLUDING
YAKUTAT.  RAPID CLEARING IS OCCURRING BEHIND THE PRECIPITATION
BAND THE CROSS SOUND AND GLACIER BAY AREAS.  A BUILDING SURFACE
HIGH OVER NORTHERN YUKON IS PRODUCING SOME GUSTY NORTHERLY
OUTFLOW WIND IN FAVORED LOCATIONS ACROSS THE NORTHERN HALF.

THE RAIN AND SNOW BAND WILL CONTINUE TO EXIT THE FORECAST AREA
FROM NORTHWEST TO SOUTHEAST THROUGH THE DAY TODAY.  ONLY EXPECT
PRECIPITATION TO LINGER IN THE SOUTHERN INNER CHANNELS TONIGHT.
TEMPERATURES WILL FALL NEAR TO BELOW FREEZING IN THESE LOCATIONS
OVERNIGHT AND THEREFORE EXPECT UP TO A FEW INCHES OF
ACCUMULATION...HIGHEST NEAR HYDER WHERE THE SNOW WILL LAST
LONGEST.

CLEARING SKIES WILL BRING THE POTENTIAL FOR SOME PATCHY FOG
OVERNIGHT.  THE LIMITING FACTOR WILL THE AMOUNT OF NORTHERLY
OUTFLOW AS THE HIGH OVER YUKON STRENGTHENS.  THE BEST FOG
POTENTIAL WILL BE IN WIND SHELTERED LOCATIONS...SUCH AS
PETERSBURG.  ADDITIONALLY...EXPECT THE NORTHERLY OUTFLOW TO BRING
A COOLER AIRMASS INTO THE PANHANDLE OVERNIGHT AND ON SATURDAY.
HOWEVER...GIVEN THAT TEMPERATURES ARE IN THE TEENS AT MOST
SURROUNDING CANADIAN LOCATIONS...DO NOT THINK THAT THIS COLD AIR
OUTBREAK WILL BE EXTREME.  WILL GO WITH LOWS IN THE UPPER TEENS
TO LOWER 20S IN THE FAR NORTH TONIGHT.

FOR SATURDAY WE CAN EXPECT THE BUILDING EASTERN GULF RIDGE TO
SHIFT FURTHER EASTWARD IN RESPONSE TO A LARGE SCALE UPPER LOW
CENTERED OVER THE ALEUTIAN CHAIN.  AT THE SURFACE...A LARGE AND
COMPLICATED LOW IS EXPECTED TO SEND A FRONT INTO THE WESTERN GULF
THROUGH TONIGHT.  A DEVELOPING SURFACE FEATURE ROTATING AROUND
THE PARENT ALEUTIAN LOW DEEPENS IN THE NORTHWESTERN GULF...WHICH
WILL FURTHER PUSH THE GULF FRONT TOWARDS OUR FORECAST AREA
SATURDAY.  MODEL CONSENSUS GENERALLY PLACES THE LEADING EDGE OF
THE ASSOCIATED PRECIPITATION AT THE WESTERN EDGE OF ZONE 17 BY
SATURDAY AFTERNOON.

.LONG TERM...FRONT BAND FROM THE NEXT SYSTEM BEGINS SPREADING
ACROSS THE EASTERN GULF AND ACROSS SOUTHEAST ALASKA SATURDAY NIGHT
AND SUNDAY. A DEVELOPING WAVE ON THE FRONT RUNS NORTHEAST TO A LOW
OVER NORTHEAST GULF BY SUNDAY MORNING... MAY HAVE ENOUGH STRONGER
WINDS AT ADVISORIES MAY BE NEEDED BY SUNDAY... BUT FOR NOW MAY
JUST LEAVE WINDY CONDITIONS THERE OR HEADLINE THE COASTAL ZONES.

THE MAIN PARENT LOW FROM THE SYSTEM IS FURTHER TO THE WEST BEING
SOUTH OF KODIAK ISLAND SUNDAY EVENING WHICH THEN DRIFTS TO
SOUTHWEST OF YAKUTAT BY TUESDAY MORNING. WHERE IT PERSIST AND
WEAKEN THROUGH THE REST OF THE WEEK.

ALOFT A BROAD UPPER LEVEL LOW DROPS TO THE WESTERN GULF BY THE END
OF THE WEEK WHILE LATER INDICATIONS ARE THAT IT WILL CONTINUE DO
DRIFT SOUTHEAST TO THE PACIFIC NORTHWEST BY THE LAST WEEK OF
MARCH...BUT THROUGH THE FORECAST PERIOD ONCE THE MAIN FRONT GOES
THROUGH SOUTHEAST ALASKA BY THE EARLY PART OF THE WEEK EXPECT
CONTINUED SHOWER ACTIVITY SPREADING SHOWER... SHOULD CONTINUE
THROUGH THE WEEK... WITH BETTER CHANCES MAINLY ALONG THE OUTER
COASTS.

TEMPERATURE TRENDS SHOW A COOLING PATTERN AS WELL AS THE 1000-500
MB THICKNESS LOWER THROUGH THE WEEK AS WELL AS THE COLD AIR WRAPS
AROUND THE UPPER LEVEL LOW. SO SHOWERS WILL LIKELY BE SNOW.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...SMALL CRAFT FOR PKZ011>013-021-022-031>034-036-041>043-051.

&&

HANKO - BEZENEK