Small Craft Advisory 368, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
140 PM ADT THU APR 19 2007

.MODEL DISCUSSION...
NCEP MODELS ARE QUITE SIMILAR TODAY THROUGH 84 HOURS. ECMWF AND UKMET
ALSO HOLD SIMILAR SOLUTION THROUGH THE SAME TIME PERIOD. IN
FACT...THE ECMWF AND GFS ARE SIMILAR THROUGH 120 HOURS OF THE
FORECAST. THE MODELS HAVE ALL INITIALIZED THE MOISTURE AND SURFACE
FIELDS RATHER WELL.

.UPPER LEVELS...
BIG PICTURE IS FOR COLD CORE LOW OVER EASTERN SIBERIA TO LIFT OVER
THE ARCTIC NORTH OF CENTRAL RUSSIA THIS WEEKEND AND REMAIN THROUGH
MID WEEK. IN THE MEANTIME...TROUGH TO REMAIN OVER THE BERING WITH A
LOBE EXTENDED TO THE GULF AND A RIDGE PUNCHING IN OVER EASTERN ALASKA
THROUGH THE WEEKEND. EARLY NEXT WEEK...A SECONDARY CLOSED LOW TO
DEVELOP OVER THE EASTERN BERING AND REMAIN THROUGH MID WEEK. THIS
PATTERN WILL ESSENTIALLY LEAVE SOUTH CENTRAL ALASKA WARM AND MOIST
WITH WESTERN ALASKA AND THE ALEUTIANS REMAINING BELOW NORMAL.

.WEST OF THE ALASKA RANGE...
FRONTAL BOUNDARY THAT MOVED THROUGH SOUTHWEST ALASKA IS BEING PUSHED
BACK THROUGH FROM THE EAST. THEREFORE AREAS OF SNOW BEING REPORTED
FROM BETHEL EAST. A LARGE LOW PRESSURE SYSTEM TO THE SOUTH OF DUTCH
HARBOR WRAPPING MOISTURE FROM THE AKPEN TO THE CENTRAL ALEUTIANS.
GALE FORCE WINDS ALSO WITH THIS SYSTEM FROM THE LOW CENTER INTO THE
EASTERN BERING. THE LOW WILL SLOWLY WEAKEN ITS INFLUENCE OVER THE
AREA TOMORROW AS IT MOVES INTO THE GULF. WINDS WILL DROP BELOW GALE
FORCE FRIDAY IN RESPONSE. IN THE MEANTIME...SNOW WILL CONTINUE OVER
THE EASTERN ALEUTIANS INTO SOUTHWEST ALASKA. SNOW AMOUNTS ARE
ANTICIPATED TO BE LIGHT THOUGH. SHOWERS WILL CONTINUE OVER SOUTHWEST
ALASKA INTO SATURDAY. ANOTHER LOW TO ROLL UP TOWARD THE WESTERN
ALEUTIANS FRIDAY NIGHT. THIS SYSTEM TO STAY A LITTLE FARTHER SOUTH
THAN THE CURRENT SYSTEM. THEREFORE...WINDS ARE NOT EXPECTED TO BE AS
STRONG ALONG THE ALEUTIANS FRIDAY NIGHT THROUGH SUNDAY AS IT STAYS TO
THE SOUTH. MOST OF THE PRECIPITATION WILL REMAIN CLOSE TO THE CHAIN
WITH LITTLE SHOWER ACTIVITY PUSHING UP TO SOUTHWEST ALASKA. THE
PRECIPITATION TYPE WILL REMAIN SNOW NORTH OF THE CHAIN WITH A MIX
ALONG THE CHAIN. ANOTHER SYSTEM TO MOVE ALONG THE CHAIN STARTING
SUNDAY AFTERNOON NEAR SHEMYA. THE LOW WILL WORK ALONG THE CHAIN INTO
TUESDAY WITH THE STRONGEST WINDS REMAINING SOUTH OF THE CHAIN AND
PRECIPITATION SPREADING ALONG THE CHAIN AND OVER THE BERING MONDAY. A
FRONT TO PUSH TO THE AKPEN WITH THIS SYSTEM TUESDAY.

.EAST OF THE ALASKA RANGE...
A WEAK FRONT OVER THE GULF DISSIPATING RAPIDLY AS THE STRONGER FRONT
IS WORKING NORTH THIS AFTERNOON. WINDS ARE STARTING TO PICK UP IN
SOUTH CENTRAL AS THE FLOW IS STRONG FROM THE SOUTH TO SOUTHEAST
ALOFT. THE FRONT WILL NOT PUSH INTO THE NORTHEAST GULF AS HIGH
PRESSURE IS OVER THE YUKON AND THE PANHANDLE. WINDS WILL REACH GALE
FORCE OVER THE OUTSIDE WATERS WITH SOME STRONG SMALL CRAFTS IN INNER
WATERWAYS. PRECIPITATION WILL FOLLOW THE TYPICAL STRONG SOUTHEAST
FLOW PATTERN. THIS ENTAILS PRECIP ALONG THE COAST FROM PRINCE WILLIAM
SOUND WEST WITH LITTLE CHANCE OVER THE WESTERN KENAI NORTH THROUGH
THE MATSU VALLEY. HOWEVER...PRECIP WILL SQUEAK THROUGH KACHEMAK BAY
AND RIDE UP ALONG THE ALASKA RANGE. THE PARENT LOW FOR ALL THIS WILL
SLIDE EAST FRIDAY AND FRIDAY NIGHT JUST SOUTH OF THE GULF.
THEREFORE...THE FRONT WILL WEAKEN OVER TIME. IN ADDITION...THE FLOW
ALOFT WILL TURN MORE EASTERLY AND BRING DRIER AIR OVER SOUTH CENTRAL
FRIDAY NIGHT AND SATURDAY. THIS RESPITE FROM MOIST CONDITIONS WILL
NOT LAST LONG. ANOTHER LOW MOVING OUT OF THE NORTH PACIFIC TO BRING
BACK MOISTURE AND GALE FORCE WINDS TO THE GULF SATURDAY NIGHT TO THE
GULF AND SPREAD TO THE GULF COAST AND SOUTH CENTRAL SUNDAY. TYPICAL
SOUTHEAST FLOW PRECIP PATTERN ONCE AGAIN. THE HIGH PRESSURE OVER THE
PANHANDLE GETS PUSHED EAST...SO PRECIPITATION AND GALE FORCE WINDS
WILL SPREAD TO THOSE AREAS THIS TIME AS WELL. THE LOW TO WEAKEN IN
THE GULF INTO TUESDAY...BUT THE PATTERN WILL REMAIN THE SAME. ALL
PRECIP LIKELY TO BE RAIN OVER SOUTH CENTRAL THROUGH THE WEEKEND AND
INTO NEXT WEEK.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...NONE
MARINE...GALE 120 130 132 150 155 165 170 172 179
FIRE WEATHER...NONE

JN APR 07