Small Craft Advisory 805, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
200 PM ADT SAT SEP 29 2007

.MODEL DISCUSSION...
ONCE AGAIN...THE MODELS ARE IN GOOD AGREEMENT SYNOPTICALLY THROUGH
WEDNESDAY. AFTER THIS PERIOD...THE UNCERTAINTY IS LARGE THROUGH THE
BERING WITH AN UPPER LOW NEXT WEEK AND ITS SPEED. EVENTUALLY A BROAD
TROUGH IS OVER THE EASTERN BERING AND MAINLAND BY NEXT WEEKEND. IN
THE SHORT TERM...THE MAJOR DIFFERENCE RIDES WITH THE DEVELOPMENT OF A
SURFACE SUNDAY NIGHT/MONDAY MORNING. THE NAM IS THE FARTHEST NORTH OF
THE SOLUTIONS. HOWEVER...THE DIFFERENCE IS ONLY WITH HOW STRONG THE
WINDS WILL BE IN THE NORTHERN GULF. WENT MORE WITH A UKMET WHICH WAS
A BLEND BETWEEN THE GFS AND NAM FOR THIS PERIOD. AFTER THIS...THOUGHT
THE GFS WAS THE PLAN OUT TO WEDNESDAY.

.ANALYSIS AND UPPER LEVELS...
A FRONT PUSHING TO THE WEST COAST THIS AFTERNOON WITH ITS PARENT LOW
JUST EAST OF THE KAMCHATKA PENINSULA. THE FRONT IS SUPPORTED WELL
WITH A STRONG 175 KT JET AND GOOD WARM ADVECTION. THE STACKED LOW
OVER THE GULF PULLING SOUTHEAST AND WEAKENING. SHOWERS ALONG THE
NORTHERN GULF COAST HAVE DIMINISHED AND CLOUDS ARE LEAVING THE AREA
AS WELL. THE WESTERN FRONT TO BRING MORE CLOUDS TO SOUTH CENTRAL
TONIGHT.

.SHORT TERM FORECAST...
ALEUTIANS AND BERING AND SOUTHWEST ALASKA...
OCCLUDED FRONT OVER THE CENTRAL BERING WITH GALE FORCE WINDS AND
MODERATE RAINFALL. THE FRONT PUSHES TO THE COAST TONIGHT WITH SHOWERS
REMAINING OVER THE BERING AND ALEUTIANS. PRECIP TO BE MODERATE TO
HEAVY AT TIMES OVER SOUTHWEST ALASKA TONIGHT. PRECIP WILL PUSH INTO
THE KUSKOKWIM VALLEY BY TOMORROW MORNING. GALE FORCE WINDS TO REMAIN
AROUND THE LOW AND BEHIND THE FRONT. THE LOW MOVES TO THE MAINLAND
SLOWLY SUNDAY AND INLAND SUNDAY NIGHT. PRECIP WILL TURN MORE SHOWERY
OVER THE MAINLAND AT THIS TIME. SOME SNOW WILL TOUCH THE HIGHER
ELEVATIONS AS WELL.

A PERSISTENT WESTERLY FLOW BEHIND THE LOW PROVIDING GOOD FETCH FOR
HIGH SURF DURING HIGH TIDE TOMORROW AND MONDAY. GALE FORCE WINDS TO
REMAIN AROUND THE LOW THROUGH THIS PERIOD. WITH SOME UPPER LEVEL
SUPPORT FROM THE JET AND SOME COLD AIR ADVECTION...EXPECT STRONG
GUSTS THROUGH THE AKPEN SUNDAY NIGHT THROUGH TUESDAY. HIGH PRESSURE
TO PUSH INTO WESTERN BERING MONDAY INCREASING THE SURFACE GRADIENT
OVER THE EASTERN BERING.

SOUTH CENTRAL ALASKA...
THE LOW IN THE GULF RIGHT NOW PULLING SOUTHEAST WITH CLOUDS AND
SHOWERS ENDING OVER THE AREA. SOME CLOUDS TO SPREAD BACK IN TONIGHT
AS THE FRONT MOVES CLOSER TO SOUTHWEST ALASKA TONIGHT. THE FLOW TURNS
SOUTHWEST AND ALLOWS DEEPER MOISTURE INTO SOUTH CENTRAL ALASKA.
SHOWERS SHOULD SPREAD GRADUALLY OVER THE AREA LATE TONIGHT AND
THROUGH TOMORROW. A SECONDARY LOW WILL DEVELOP IN THE GULF WHERE THE
JET SUPPORT FAVORS DEVELOPMENT SUNDAY NIGHT. THIS WILL TAKE SOME OF
THE ENERGY AND MOISTURE FROM THE MAINLAND. HOWEVER...THE FLOW ALOFT
REMAINS SOUTHWEST FOR SCATTERED SHOWERS TO REMAIN OVER THE MAINLAND
MONDAY. IN ADDITION...THE MAIN UPPER LOW MOVES OVER THE AREA MONDAY
KEEPING WITH A COOLING TREND THROUGH THE NEXT WEEK. THE FLOW TURNS
NORTHWEST TUESDAY AND THE DRYING BEGINS. THE AIR MASS THEN TURNS
COLDER AND DRIER WEDNESDAY.

.LONG TERM FORECAST...
BROAD COLD TROUGH OVER THE MAINLAND WITH A SURFACE LOW OVER THE GULF
THROUGH NEXT WEEK. THE AIR MASS WILL BE DRYING WITH DIMINISHING
SHOWERS ALONG THE MOUNTAINS. A LOW WILL MOVE INTO THE GULF LATE IN
THE WEEK. THE TIMING OF THIS FEATURE IS UP FOR DEBATE. IN THE
BERING...HIGH PRESSURE OVER THE AREA IN THE MID WEEK BEFORE A LOW
PUSHES ACROSS THE BERING WEDNESDAY AND THURSDAY THEN HIGH PRESSURE
RETURNS FOR THE WEEKEND.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...HIGH SURF ADVISORY ZONES 155 AND 161
MARINE...GALE 150 15 160 165 170 172 175 176 179
FIRE WEATHER...NONE

JN SEP 07