Small Craft Advisory 45, NWS Anchorage, AK

AREA FORECAST DISCUSSION...CORRECTION
SOUTHCENTRAL AND SOUTHWEST ALASKA
400 PM AST TUE JAN 15 2008

CORRECTED WATCH/WARNING SUMMARY

.MODEL DISCUSSION...MODELS IN GOOD AGREEMENT IN THE NEAR TERM. THEY
DO DIVERGE RATHER QUICKLY AFTER 36 HOURS...ESPECIALLY WITH THE
MOVEMENT OF FRONTAL WAVES IN THE GULF OF ALASKA. THE BERING SEA
LOW TRACK THROUGH 120 HOURS IS ALMOST IDENTICAL AMOUNG THE
MODELS...HOWEVER THEIR TIMING IS VERY DIFFERENT. THIS IS NOT A HUGE
SURPRISE IN THIS TYPE OF PATTERN. THEREFORE THERE IS NOT A HUGE
DEGREE OF CONFIDENCE IN THE MODELS AT THIS TIME.

.ANALYSIS AND UPPER LEVELS...THE MOST STRIKING FEATURE WHEN LOOKING
AT THE SATELLITE IS THE JET STREAM AND ASSOCIATED FRONTAL BOUNDARY
THAT EXTENDS FROM AROUND 25N 180W INTO SOUTH CENTRAL ALASKA.
A STRONG LOW JUST NORTH OF THE PRIBILOF ISLANDS WILL MOVE INTO NORTON
SOUND OVERNIGHT. ANOTHER LOW SOUTH OF KISKA ISLAND THIS AFTERNOON
WILL MOVE WEST OF THE PRIBILOF ISLANDS THURSDAY. THIS WILL KEEP THE
SOUTHWEST FLOW OVER SOUTHWEST ALASKA AND THE EASTERN HALF OF THE
ALEUTIANS THROUGH THE MIDDLE OF THE WEEK. AN INTERESTING FEATURE
SOUTH OF DUTCH HARBOR IS A POLAR LOW THAT IS A BIT STRONGER THAN THE
MODELS ARE SHOWING. THIS LOW IS DECOUPLED FROM THE JET STREAM BUT IS
STILL HOLDING TOGETHER AND MOVING STEADILY NORTHEAST.

.SHORT TERM FORECAST...THE LARGE FRONT OVER THE WESTERN GULF AND
SOUTH CENTRAL ALASKA IS BRINGING A LOT OF MOISTURE THAT IS OVERRIDING
THE COLD AIR THAT IS ENTRENCHED OVER THE AREA. THIS RESULTING SNOW IS
LIKELY TO PERSIST OVER THE PRINCE WILLIAM SOUND AREA INTO WEDNESDAY.
THE SUSITNA VALLEY IS ALSO RECEIVING A GOOD AMOUNT OF SNOW WITH THE
SNOW ADVISORY IN ZONE 145 VERIFYING NICELY. THE SHORT TERM WILD CARD
IS THE POLAR LOW SOUTH OF DUTCH HARBOR. THE NAM HAS IT MOVING INTO
PRINCE WILLIAM SOUND TOMORROW. THIS COULD PRODUCE MORE SNOWFALL IN
THE SOUTH CENTRAL AREA SHOULD IT TAKE THIS TRACK.

.LONG TERM FORECAST...NOT A BIG CHANGE IN THE OVERALL PATTERN BETWEEN
NOW AND THE WEEKEND. A LARGE UPPER LEVEL RIDGE WILL REMAIN OVER THE
WEST COAST OF NORTH AMERICAN AND THE JET STREAM WILL CONTINUE TO
BRING SOUTH TO SOUTHWEST FLOW OVER THE STATE.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...SNOW ADVISORY 145.
MARINE...GALE 120 125 150 160 165 172 179 180 351 352 412 414.
         HEAVY FREEZING SPRAY 140 185.
FIRE WEATHER...NONE.

JAN 08