Small Craft Advisory 128, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
200 PM AST SAT FEB 3 2007

.DISCUSSION...
MODELS SEEM TO HAVE INITIALIZED WELL THIS MORNING. HOWEVER...THE
DETAILS ARE NOT THAT WELL REPRESENTED WITH THE LOW JUST SOUTH OF THE
WESTERN ALEUTIAN CHAIN. THE SYSTEM LOOKS TO BE A BIT STRONGER THAN
THE MODELS HAVE INDICATED. GFS HAS A BETTER HANDLE ON THE POSITION OF
THE LOW THAN THE NAM. FURTHER OUT IN TIME...BELIEVE THE MULTIPLE
CENTER LOW STRUCTURE IN THE BERING AS WELL. THIS IS HELD BY MOST
MODELS...BUT SINCE WE WILL STICK WITH THE GFS IN THE SHORT TERM WILL
HOLD ONTO IT IN THE MEDIUM RANGE AS WELL.

UPPER LEVELS...LARGE TROUGH OVER THE BERING WITH HIGH PRESSURE OVER
THE WEST COAST OF THE LOWER 48 ALL THE WAY TO THE NORTH POLE. HIGH
PRESSURE TO DEVELOP OVER THE INTERIOR OF ALASKA EARLY NEXT WEEK AS
THE TROUGH IN THE BERING BECOMES NEGATIVELY TILTED. BY LATE THIS
WEEK...THE TROUGH IN THE BERING RETROGRADES TO THE WESTERN BERING
WITH HIGH PRESSURE OVER THE ENTIRE MAINLAND INTO THE EASTERN BERING.
ONLY ONE SHORT WAVE TROUGH TO MOVE THROUGH THE MAINLAND DURING THIS
TIME. IT IS A DISSIPATING SHORT WAVE WITH LITTLE PRECIPITATION
REACHING SOUTH CENTRAL.

EAST OF THE ALASKA RANGE...HIGH PRESSURE TO REMAIN OVER THE INTERIOR
AS A TROUGH OF LOW PRESSURE MOVES ALONG THE NORTHERN GULF COAST THIS
EVENING. THIS WILL BUILD UP A PRESSURE GRADIENT FAVORABLE FOR
NORTHERLY WINDS ALONG THE NORTHERN COAST. WITH A LOW MOVING TOWARD
SITKA...THE UPPER FLOW BECOMES NORTHERLY AS WELL...SO THERE SHOULD BE
SOME ENHANCED GAP FLOWS FROM THE WESTERN PRINCE WILLIAM SOUND
EASTWARD. THE GRADIENT LOOSENS BY MONDAY MORNING THROUGH. DO NOT
EXPECT TO SEE MUCH WIND THROUGH THE INLET IN THIS SCENARIO...SO WILL
LIKELY SEE FOG OVER THESE AREAS TONIGHT AND SUNDAY NIGHT. MAY HAVE A
BIT OF WIND THROUGH THE MATANUSKA AND UPPER SUSITNA THOUGH. A FRONT
MOVES ACROSS KODIAK TUESDAY WITH SOME PRECIPITATION AND SOUTHEAST
WINDS. THE WIND AND PRECIPITATION TO WORK TO THE NORTHERN GULF COAST
WEDNESDAY MORNING. THE FRONT WILL WEAKEN AND MOVE ACROSS SOUTH
CENTRAL ALASKA WEDNESDAY AFTERNOON AND EVENING. AFTER THE FRONT...A
QUICK RETURN TO DRY CONDITIONS. A TROUGH REMAINS OVER THE NORTHERN
GULF COAST THURSDAY WITH HIGH PRESSURE INLAND. THEREFORE...ENHANCED
NORTHERLY GAP WINDS SHOULD RETURN TO THE WESTERN PRINCE WILLIAM SOUND
AREA EASTWARD FOR THURSDAY AND FRIDAY.

WEST OF THE ALASKA RANGE...A 950 MB LOW MOVING ACROSS THE WESTERN
ALEUTIAN CHAIN THIS AFTERNOON. VERY STRONG WINDS ARE ASSOCIATED WITH
THIS LOW FROM KISKA TO DUTCH HARBOR. THESE WINDS TO SPREAD NORTH
THROUGH THE BERING TONIGHT REACHING THE PRIBILOFS BY MIDNIGHT. HAVE
ISSUED HIGH WIND WARNINGS FOR THE ALEUTIANS. BELIEVE TEMPERATURES
WILL BE RELATIVELY WARM ENOUGH TO NOT WARRANT A BLIZZARD WARNING FOR
THE PRIBILOFS TONIGHT. IT WILL DEFINITELY BE ALL RAIN OVER THE
PRIBILOFS BY TOMORROW BUT MAY TURN TO RAIN BY MIDNIGHT OR SHORTLY
AFTER WITH THE PUSH OF THE FRONT. WINDS TO PICK UP OVER THE EASTERN
ALEUTIANS AND WEST COAST OF ALASKA TONIGHT AS WELL BUT NOT TO WARNING
LEVELS. THE WINDS OVER THE ALEUTIANS WILL DROP BELOW WARNING LEVELS
LIKELY LATE TONIGHT. PRECIP NOT LIKELY TO MAKE TO THE WEST COAST
UNTIL MONDAY NIGHT AS THE MAIN LOW PUSHES EAST BUT REMAINS SOUTH OF
THE CHAIN. THE LOW FINALLY CROSSES THE CHAIN TUESDAY MORNING AND INTO
THE NORTHERN BERING SEA TUESDAY NIGHT. THIS WILL PUSH THE FRONT ALONG
THE WEST COAST INLAND AND THROUGH THE MAINLAND WEDNESDAY. ANOTHER LOW
WILL MOVE OUT OF THE NORTH PACIFIC WEDNESDAY ACROSS THE ALEUTIAN
CHAIN. THE LOW WILL MOVE INLAND WEDNESDAY NIGHT AND BRING SOME
PRECIPITATION. IN THE MEANTIME...A LARGE LOW PRESSURE SYSTEM WILL
WORK INTO THE WESTERN ALEUTIAN CHAIN WEDNESDAY NIGHT AND PUSHES A
FRONT INTO THE CENTRAL BERING SEA. THE LOW AND FRONT RIDE NORTH
FRIDAY BUT DO NOT MAKE IT TO THE WEST COAST OF ALASKA.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...HIGH WIND WARNING ZONE 185 AND 187
         FLOOD WATCH ZONE 121
MARINE...STORM 155 170 171 172 175 176 179
         GALE 160 165 180 185
FIRE WEATHER...NONE

JN FEB 07