Heavy Snow in Alaska, December 15, 2003

SOUTHEAST ALASKA FORECAST DISCUSSION
1045 AM AST MON DEC 15 2003

.SHORT RANGE...STRONG FRONT MOVING THROUGH THE PANHANDLE THIS
MORNING. PRESSURE RISING ALONG NORTHERN COASTAL ALREADY AT 18Z.
CHANGE IN MODELS WITH FRONTAL WAVE NOW DEVELOPING NEAR 48N/135W.
PREVIOUS RUN TOOK CLOSED LOW NORTH ALONG OUTER COAST OF
PANHANDLE...12Z ETA MOVES LITTLE WEAKER LOW INTO SOUTHERN
PANHANDLE. CURRENT POSITION AND UPPER WINDS LOOK TO SUPPORT
FURTHER EAST TRACK OF 12Z RUN. THAT WILL CAUSE WINDS TO DROP
QUICKER OVER MOST ZONES THAN IN CURRENT FORECASTS AS PRESSURES
FALL TO THE SOUTH WITH APPROACHING FRONTAL LOW. WILL DROP MOST OF
THE WIND ADVISORIES AND WARNINGS THIS MORNING. WIND WARNINGS OVER
ZONES 27 28 HANGING ON A LITTLE LONGER BUT DROPPING BY THIS
AFTERNOON OVER SOUTHERN. HEAVIEST PRECIP OVER SOUTHERN HALF TODAY
ALSO.

OTHER PROBLEM THAT CAUSES IS WITH THE PRECIP TYPE OVER NORTHERN
ZONES. DEFINITELY DELAYS SWITCH OVER FROM SNOW TO RAIN OVER INNER
CHANNELS OF CENTRAL PANHANDLE...IE ZONES 21 AND 25. WILL LIKELY
KEEP SOME SNOW OVER THE AREA INTO TONIGHT UNTIL LOW JUMPS INLAND
AND SOUTHERLY PUSH TAKES OVER.

BY LATER TONIGHT MAIN WEATHER FEATURE WILL BE SHOWERS ROTATING
AROUND WARM-CORE LOW CENTER OVER THE WESTERN GULF OF ALASKA.
MODELS PICK UP ON ONE ORGANIZED BAND MOVING ONSHORE AFTER 12Z
WITH MODERATE-HEAVY SHOWERS INTO TUE.

.LONG RANGE...THE VERTICALLY STACKED LOW IN THE CENTRAL GULF
TUESDAY AFTERNOON WILL CONTINUE TO FILL AND DRIFT NORTHWARD TO BE
OVER PRICE WILLIAM SOUND BY WEDNESDAY EVENING. SHOWERS WILL
PERSIST THROUGH THAT TIME PERIOD AND THE PRESSURE GRADIENT WILL
REMAIN TIGHT SO WINDS WILL REMAIN ON THE WINDY SIDE. AN LONG WAVE
TROF ASSOCIATED WITH A UPPER LEVEL LOW OVER THE NORTHERN BEARING
WILL SWING ACROSS THE PANHANDLE ON THURSDAY. THIS WILL BRING A
CHANCE OF SHOWERS TO SOUTHEAST BUT WITH A BUILDING RIDGE IN
CANADA SO THE INNER CHANNELS COULD BE JUST CLOUDY. AREAS CLOSER
TO THE COAST WILL HAVE A HIGHER CHANCE AS THE FLOW ALOFT WILL BE
ONSHORE AND THERE IS MODERATE MID LEVEL MOISTURE AND ENERGY.
AFTER THE UPPER LEVEL TROF MOVES THROUGH A UPPER RIDGE WILL MOVE
OVER THE AREA THURSDAY NIGHT AND WITH THE SURFACE FLOW OFFSHORE
THE CHANCE OF PRECIP WILL GO DOWN. BY FRIDAY MORNING THE UPPER
RIDGE AXIS MOVES PASSED THE PANHANDLE AND ONSHORE FLOW INCREASES
SO A CHANCE OF PRECIP WILL INCREASE.

A SERIES OF WARM DEVELOPING WAVES WILL BE MOVING OUT OF THE NORTH
PACIFIC BEGINNING FRIDAY NIGHT AND CONTINUING THROUGH MONDAY. SO
PRECIPITATION WILL BE LIKELY THROUGH THE WEEKEND AND INTO MONDAY.

A LOW WILL BE OFF THE COAST ON SATURDAY AND THEN ANOTHER ON
MONDAY.

.AJK...WATCHES/WARNINGS/ADVISORIES
PUBLIC...HIGH WIND WARNING ZONES 27 28 ENDING EARLY AFTERNOON.
         HIGH WIND WARNING CANCELLED ZONES 22 23.
         WIND ADVISORY ZONE 26.
         CANCEL WIND ADVISORIES 17 20 21 24 25.
         HEAVY SNOW WARNING ZONE 29.
         SNOW ADVISORY ZONE 19 THIS AFTERNOON.
         CANCEL SNOW ADVISORY ZONE 18.
MARINE...SEE NEW AMENDED 21Z CWFAJK AND CWFAEG.

PES/ABJ

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE JUNEAU AK
1001 AM AST MON DEC 15 2003

TIME(AST)  .....CITY LOCATION.....STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0645 AM    HYDABURG                  AK   69 MPH NON-TSTM WND GST
12/15/03   CRAIG COASTAL

CTM