Gale Warning 19, NWS Juneau, AK

SOUTHEAST ALASKA FORECAST DISCUSSION
1100 AM AST THU JAN 4 2007

.SYNOPSIS...
.SHORT RANGE...SIGNIFICANT WINTER STORM POSSIBLE OVER PARTS OF
SOUTHEAST ALASKA LATER TONIGHT AND WEDNESDAY MORNING. MORNING
WATER VAPOR LOOP SHOWS A VERY COMPLEX UPPER AIR PATTERN OVER THE
NORTH PACIFIC AND GULF OF ALASKA. THE MAIN LOW APPEARS TO BE WELL
TO OUR WEST OVER THE WESTERN ALEUTIANS. THIS MAIN LOW WILL REMAIN
WEST OF SOUTHEAST ALASKA AS ANOTHER WAVE DEVELOPS IN RESPONSE TO
A 170 KT JET THAT IS FORECAST TO MOVE ACROSS THE NORTH CENTRAL
PACIFIC LATER THIS AFTERNOON.

A SURFACE LOW IS EXPECTED TO DEVELOP OVER THE CENTRAL GULF BY
EARLY EVENING TONIGHT AND THEN MOVE INTO THE NORTHERN PANHANDLE
OVERNIGHT. MOST OF THE NORTHERN AND CENTRAL PANHANDLE REGION IS
BELOW FREEZING...AND LITTLE IN THE WAY OF WARMING IS EXPECTED
DURING THE DAY IN SPITE OF THE PARTLY SUNNY SKIES THAT ARE BEING
EXPERIENCED TODAY. A FEW SNOW SHOWERS CONTINUE OVER PORTIONS OF
THE AREA...BUT THE SNOW IS EXPECTED TO INCREASE LATER THIS
AFTERNOON AS THE LOW DEVELOPS AND MOVES CLOSER TO THE PANHANDLE.
SNOW SHOWERS SHOULD BECOME MORE STRATIFORM AS A WARM ADVECTION
PROFILE BECOMES ESTABLISHED OVER THE AREA. THERE IS STILL SOME
QUESTION AS TO IF OR WHEN SNOW WILL MIX WITH RAIN OVER THE
NORTHERN PANHANDLE AS SOME SLIGHTLY WARMER AIR TRIES TO ADVANCE
NORTHWARD AHEAD OF THE COLD FRONT. DUE TO THE RAPID MOVEMENT OF
THE FRONT...ANY RAIN WOULD LIKELY BE SHORT LIVED AND WILL RETURN
TO SNOW IN THE POST FRONTAL ENVIRONMENT. SNOW WILL LIKELY BE
HEAVY AT TIMES AS THE STRONG OMEGA PATTERN ASSOCIATED WITH THE
UPPER TROUGH MOVES ACROSS THE PANHANDLE. SNOW TOTALS OF 5 TO 10
INCHES ARE VERY LIKELY BY TOMORROW MORNING BEFORE THE SYSTEM
MOVES OFF TO THE EAST. THE HIGHEST AMOUNTS LOOK TO BE OVER THE
NORTHERN PANHANDLE WHERE THE WARMER PRE-FRONTAL AIR IS LEAST
LIKELY TO OCCUR.

THE STRONGEST WINDS ASSOCIATED WITH THIS SYSTEM LOOK TO BE ACROSS
THE SOUTHERN PARTS OF THE PANHANDLE. THE LOW IS LIKELY TO BE
WEAKER THAN CYCLONES WE HAVE SEEN IN THE PAST WEEK OR TWO SO
DONT EXPECT TO SEE STORM FORCE WINDS ALTHOUGH GALES ARE LIKELY
OVER THE CENTRAL AND SOUTHERN OUTER WATERS AND PARTS OF THE
CENTRAL AND SOUTHERN INNER WATERS. WIND ADVISORIES LOOK TO BE
NEEDED FOR AREAS ALONG AND SOUTH OF A LINE FROM SITKA TO ANGOON
TO WRANGELL.

.LONG RANGE...GFS AND EUROPEAN CONSENSUS IS GOOD...AND THEY
ARE DROPPING THE WHOLE POLAR FRONT ZONE AT LEAST 3 DEG
LATITUDE THIS WEEKEND THROUGH TUE.  ARCTIC OUTBREAK
FOR BEGINNING MON NIGHT AND TUE ALSO HAS STRONGER PRESSURE
GRADIENTS AND WILL BE USED FROM THE NEW 40 KM GRIDS.  GFS
MOS TEMPS WILL BE USED BEYOND DAY THREE.

.AJK...WATCHES/WARNINGS/ADVISORIES
PUBLIC...HEAVY SNOW WARNING NOON TODAY TO 9 PM TONIGHT AKZ024-026 HEAVY SNOW WARNING 3 PM
TODAY TO 3 AM FRI AKZ019>022-025 HEAVY SNOW WARNING NOON TODAY TO 6 AM FRI AKZ029 SNOW
ADVISORY 6 PM TONIGHT TO 6 AM THU AKZ018 SNOW ADVISORY NOON TODAY TO 6 PM TONIGHT
AKZ023-027-028
MARINE...GALE WARNING PKZ036-041>043-310 SCA PKZ012-021-022-031>035-051-052

MLR JT