Small Craft Advisory 207, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
200 PM AST MON FEB 26 2007

.DISCUSSION...
NCEP MODELS HAVE INITIALIZED RATHER WELL THIS MORNING. EUROPEAN
MODELS ALSO AGREEING WELL WITH THE NCEP MODELS THROUGH 72 HOURS. NEW
EXTENDED MODELS NOT IN JUST YET.

IN GENERAL...LONG WAVE TROUGHS TO REMAIN OVER EASTERN ALASKA THROUGH
THE PANHANDLE AND NEAR THE KAMCHATKA PENINSULA WITH A RIDGE OVER THE
BERING THROUGH THE WEEK.

UPPER LEVELS...STRONG RIDGE OVER THE BERING THIS MORNING TO BE
KNOCKED DOWN BRIEFLY TONIGHT AND TUESDAY BY A SHORT WAVE TROUGH
MOVING OUT OF THE LOW SOUTHWEST OF THE WESTERN ALEUTIANS. THE RIDGE
TO RE-ESTABLISH ITSELF WEDNESDAY AS TROUGH REDEVELOPS SOUTHWEST OF
THE WESTERN ALEUTIANS. THIS LOW IS REINFORCED BY ANOTHER LOW MOVING
TO THE KAMCHATKA PENINSULA. THE LOW SOUTH OF THE ALEUTIANS UNDERCUTS
THE HIGH OVER THE BERING AND DRIVES EAST SOUTH OF THE GULF OF ALASKA
FRIDAY. THE HIGH OVER THE BERING DEVELOPS ITS AXIS OVER THE WESTERN
ALEUTIAN WITH A LOW REMAINING OVER THE KAMCHATKA PENINSULA. THIS
PATTERN TO REMAIN THROUGH THE WEEKEND. IN THE MEANTIME...TROUGH TO
REMAIN OVER EASTERN ALASKA...YUKON AND THE PANHANDLE. HOWEVER...THE
SLIGHTLY WARMER TEMPS ALOFT THAT MOVED IN LAST NIGHT WILL BE REPLACED
AGAIN. A STRONG SHORT WAVE MOVING OUT OF THE NORTH TO BRING COLDER
AIR BACK WEDNESDAY WITH A TROUGH ORIENTATED FROM 80N 110W TO 50N 160W
THROUGH THE NORTHERN PANHANDLE BY FRIDAY. ONCE AGAIN THIS PATTERN TO
REMAIN THROUGH THE WEEKEND.

SURFACE WEST OF THE ALASKA RANGE...A LOW JUST SOUTH OF SHEMYA WITH A
FRONT TO PUSH ACROSS THE BERING SEA TONIGHT AND TO THE COAST BY
TUESDAY AFTERNOON. MODERATE WINDS AND PRECIPITATION WILL RUN WITH THE
FRONT. THE FRONT HAS GOOD SUPPORT ALOFT BUT WILL SHEAR APART ONCE IT
RUNS INLAND TUESDAY NIGHT AS IT HITS THE STRONG TROUGH OVER EASTERN
ALASKA. THE LOW WILL WRAP BACK TOWARD KAMCHATKA TUESDAY NIGHT AS
ANOTHER LOW MOVES CLOSER TO THE WESTERN ALEUTIANS. THIS NEXT LOW TO
MOVE A FRONT TO THE WESTERN AND CENTRAL ALEUTIANS AND BERING SEA
WEDNESDAY. HOWEVER...IT GETS STOPPED BY STRONG HIGH PRESSURE OVER THE
EASTERN BERING AND SOUTHWEST ALASKA. THE GRADIENT DEVELOPED OVER THE
BERING SEA WEDNESDAY AND THURSDAY DUE TO THE COLD AIR IN PLACE TO THE
NORTH WILL CREATE STRONG EASTERLY WIDNS OVER THE EASTERN AND NORTHERN
BERING SEA. WITH A JET WELL TO THE SOUTH...THE PARENT LOW WILL SLIDE
SOUTH OF THE ALEUTIAN CHAIN WITH THE FRONT SHEARING APART OVER THE
BERING SEA THURSDAY NIGHT. PART OF THE LOW TO SWING BACK TO KAMCHATKA
AS WELL. HIGH PRESSURE THEN BECOMES THE DOMINANT FEATURE OVER THE
BERING SATURDAY AND SUNDAY WITH A LOW WELL TO THE WEST OF SHEMYA
BRINGING SOME PRECIPITATION AND WIND TO THAT AREA SUNDAY.

SURFACE EAST OF THE ALASKA RANGE...UPPER LEVEL DISTURBANCE MOVING
THROUGH COMBINED WITH STRONG PRESSURE GRADIENT ALONG THE COAST AND
MODERATE TO STRONG WINDS ALOFT HAVE PRODUCED STRONG NORTHERLY GAP
WINDS IN AREAS EAST OF ANCHORAGE ALONG THE COAST. WINDS ARE EXPECTED
TO REMAIN STRONG THROUGH TONIGHT AND DROP OFF TOMORROW AS THE FLOW
ALOFT WEAKENS AS THE HIGH PRESSURE OVER SOUTHWEST ALASKA MOVES OVER
THE INTERIOR. SURFACE PRESSURE TROUGH TO REMAIN ALONG THE NORTHERN
COAST THROUGH THE WEEK WEAKENING FROM TIME TO TIME THOUGH. A FRONT
MOVING ALONG THE ALEUTIAN CHAIN TO CREATE A WEAK LOW IN THE GULF AND
REINFORCE THE SURFACE TROUGH WEDNESDAY. THIS FEATURE WILL ALSO BRING
SOME SHOWERS TO KODIAK AND THE GULF. A STRONG SURGE OF COLD AIR TO
PUSH FROM THE NORTH WEDNESDAY NIGHT. THIS WILL ENHANCE THE LOW IN THE
GULF AS WELL. THE SURGE WILL LIKELY BRING THE NEXT ROUND OF STRONG
WINDS TO THE AREA. THIS SYSTEM IS WELL SUPPORTED THROUGH THE
ATMOSPHERE AND THERE WILL BE STRONG WINDS OVER MUCH OF SOUTH CENTRAL.
THE COLD AIR WILL SETTLE OVER THE AREA AND REMAIN THROUGH FRIDAY. A
RIDGE WILL PUSH OVER THE MAINLAND THIS WEEKEND AND WARM TEMPERATURES
INTO SUNDAY.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...NONE
MARINE...GALE...120 130 172 185
         HEAVY FREEZING SPRAY...120 121 125 129 130 180 185
FIRE WEATHER...NONE

JN FEB 07