High Wind in Alaska, December 21 to 22, 2003

SOUTHEAST ALASKA FORECAST DISCUSSION
245 AM AST SUN DEC 21 2003

.SYNOPSIS...
.SHORT RANGE...A DEEPENING LOW OVER THE GULF OF ALASKA IS MOVING
NORTH TOWARDS PRINCE WILLIAM SOUND SUNDAY AND SUNDAY NIGHT. THE
ASSOCIATED WEATHER FRONT WILL MOVE INTO SOUTHEAST ALASKA AND
THEN INTO CANADA LATE SUNDAY INTO MONDAY. THERE IS A FAIRLY
STRONG BAND OF WINDS AHEAD OF THE FRONT WHICH LOOKS STRONG ENOUGH
TO BUMP THE MARINE ZONES OVER THE OUTER WATERS TO STORMS AND TO
UPGRADE THE HIGH WIND WATCH TO WARNING FOR THE COASTAL AREAS FROM
DIXON ENTRANCE TO CAPE SUCKLING AND THE SOUTHERN INNER CHANNELS.

WINDS OF 30 TO 40 MPH WITH GUSTS OF 60 TO 70 MPH ALONG THE COAST
AND GUSTS OF 40 TO 55 MPH ARE POSSIBLE OVER THE INNER CHANNELS.

THERE IS A SECONDARY WAVE ON THE FRONT FURTHER TO THE SOUTH ABOUT
40N EARLY THIS MORNING THIS WILL SLOW THE EASTWARD MOVEMENT AND
PREVENT IT FROM PUSHING THROUGH THE PANHANDLE QUICKLY. AS THE
WAVE ROLLS NORTH INTO THE EASTERN GULF THE FRONT WILL THEN PUSH
THROUGH THE PANHANDLE MONDAY.

.LONG RANGE...MODELS CHANGE SOMEWHAT WITH EACH NEW RUN...HOWEVER
...THE LONG RANGE MODELS HAVE BEEN CONSISTENT IN FORECASTING A
SIGNIFICANT COOLING TREND BEGINNING WITH WED NIGHT IN MOST AREAS
AND CONTINUING THROUGH THE END OF THE WEEK.

BY MON NIGHT THE FORMERLY STRONG LOW WILL BE WEAKENING OVER THE
YUKON AND CONTINUING TOWARD THE NORTHEAST. NORTH WINDS BEHIND
THE LOW WILL BRING SOME COOLER UNSTABLE AIR FROM THE ALASKAN
INTERIOR TO THE EASTERN GULF COAST AND SOUTHEAST ALASKA.

THIS WILL TRANSFORM THE STEADY PRECIPITATION TO SHOWERS MON
NIGHT. MOST INTENSE PORTION OF THE COOLER AIR WILL BE OVER
THE EASTERN GULF COAST AND NORTHERN SOUTHEAST ALASKA WHERE
SHOWERS WILL BE IN THE FORM OF SNOW IN THE CASE OF THE EASTERN
GULF COAST OR MIXED RAIN AND SNOW OVER NORTHERN SOUTHEAST ALASKA
ELSEWHERE...RAIN SHOWERS WILL PREVAIL.

ON TUE...COLD BROAD TROUGH WILL PERSIST ALONG THE EASTERN
GULF COAST. A NEW LOW FORMING OVER THE EASTERN PACIFIC WILL
BEGIN MOVING TOWARD THE OUTER COAST OF SOUTHEAST ALASKA.
AS A RESULT RAIN WILL BECOME MORE UNIFORM OVER CENTRAL AND
SOUTHERN SOUTHEAST ALASKA IN THE WARM ADVECTION AHEAD OF THE
APPROACHING LOW. SCATTERED SNOW OR MIXED RAIN AND SNOW SHOWERS
WILL PREVAIL ALONG THE EASTERN GULF COAST AND EXTREME NORTHERN
SOUTHEAST ALASKA TUE AND TUE NIGHT.

ON WED...LOW ALONG THE OUTER COAST OF SOUTHEAST ALASKA WILL
WILL MOVE NORTHEAST TO CANADA ALONG THE COLD TROUGH OVER THE
EASTERN GULF OF ALASKA TO MOVE OVER SOUTHEAST ALASKA BY
WED NIGHT. SUBSTANTIALLY COLDER AIR ASSOCIATED WITH THIS
TROUGH WILL SPREAD OVER THE ENTIRE REGION. THEREFORE SNOW SHOWERS
OVER THE EASTERN GULF COAST AND EXTREME NORTHERN SOUTHEAST
ALASKA WILL SPREAD TO THE REMAINDER OF THE REGION WED NIGHT.

CHRISTMAS DAY THROUGH FRIDAY PATTERN FEATURES A COLD TROUGH
CENTERED IN THE NORTHEAST GULF OF ALASKA  AT THE SURFACE AND
COLD ADVECTION ASSOCIATED WITH A WEST TO NORTHWEST FLOW ALOFT.
THIS PATTERN WILL CONTINUE TO GENERATE MOSTLY CLOUDY SKIES
ALONG WITH SCATTERED SNOW SHOWERS FROM THE EASTERN GULF COAST
TO THE NORTH HALF OF SOUTHEAST ALASKA AND MIXED RAIN AND SNOW
SHOWERS FOR THE SOUTH HALF OF SOUTHEAST ALASKA.

ON SATURDAY...A CLEARING TREND AS HIGH PRESSURE OVER THE YUKON
BEGINS TO DROP SOUTHEAST INTO BRITISH COLUMBIA.L

.AJK...WATCHES/WARNINGS/ADVISORIES
PUBLIC...HIGH WIND WATCH UPDATED TO WARNING FOR THIS AFTERNOON
AND TONIGHT FOR 17, 22-23, 27-28 ...WIND ADVISORY FOR THIS
AFTERNOON AND TONIGHT FOR ZONES 18-21, 24-26, 29
MARINE...STORM...41-51 GALE...11,21>31, 33>36 SMCR...12-13, 32

BMB/DED