Small Craft Advisory 732, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
515 AM ADT FRI SEP 7 2007

.ANALYSIS...
A VERTICALLY STACKED LOW OVER THE CENTRAL ALEUTIANS IS THE MAIN
WEATHER FEATURE TODAY AS IT IS BRINGING GALE FORCE WINDS TO THE
WESTERN AND EASTERN ALEUTIAN ISLANDS AND THE BERING. IT SPREAD ITS
FIRST FRONT OVER THE WESTERN ALASKAN COAST LAST NIGHT AND IS
CURRENTLY PUSHING ANOTHER STRONGER FRONT ACROSS THE ALEUTIAN CHAIN
JUST WEST OF UNALASKA. THE OLD FRONT IS DISSIPATING ACROSS THE
MAINLAND AND BRINGING SHOWERS TO SOUTHCENTRAL. ANOTHER LOW IS
STRENGTHENING NEAR THE KAMCHATKA PENINSULA AND SLOWLY MOVES SOUTHEAST
INTO THE BERING. A WARM FRONT IS HEADING NORTH THROUGH THE GULF TO
REACH THE NORTH GULF COAST THIS EVENING. A RIDGE LIES ALONG THE NORTH
GULF COAST.

.MODEL DISCUSSION...
ALL MODELS IN FAIR AGREEMENT WITH THE CURRENT BERING LOW...EXCEPT NAM
WAS OFF AGAIN WITH THE 00Z POSITION...OVER 200 MILES TO THE WEST OF
THE ACTUAL POSITION. THEN 12 HOURS LATER IT COMES MORE INTO AGREEMENT
WITH THE OTHER MODELS. THE MODELS THEN DIVERGE ON THE POSITION OF THE
LOW NEAR KAMCHATKA AS IT DROPS DOWN INTO THE BERING TO COMBINE WITH
THE PREVIOUS LOW. THE MODELS HAVE SEEMED TO BE PERSISTENT AND HAVE
RELATIVE AGREEMENT WITH BRINGING THE DISSIPATING TYPHOON FITOW
CURRENTLY NEAR JAPAN TO THE WESTERN ALEUTIANS SUNDAY. THIS IS LEADING
TO MORE CONFIDENCE IN THE LONGER TERM FORECAST.

.UPPER LEVELS...
A LARGE UPPER LOW IS SITUATED OVER THE CENTRAL ALEUTIANS WHILE A
BROAD RIDGE IS OVER THE GULF REACHING INTO THE EASTERN MAINLAND. THE
BERING LOW WILL MOVE SLOWLY EAST PUSHING MULTIPLE SHORTWAVES AROUND
IT THROUGH TONIGHT. IT WILL THEN WEAKEN AND MOVE NORTH SATURDAY AS A
LOW OVER WESTERN RUSSIA DROPS INTO THE BERING. A SHORTWAVE WILL PICK
UP THE FORMER TYPHOON FITOW SUNDAY AND WRAPPING IT INTO THE BERING BY
MONDAY TO BRING AT LEAST MAXIMUM GALES. THE LARGE LOW LOOKS TO HOLD
ON OVER THE CENTRAL BERING THROUGH THE MIDDLE OF NEXT WEEK.

.SHORT TERM FORECAST...
SOUTHCENTRAL...THE RIDGE ALONG THE NORTH GULF COAST IS BEING SQUEEZED
AS THE WARM FRONT IN THE GULF PUSHES INTO THE COAST. THE ALREADY
PRESENT GAP WINDS WILL BE INCREASING TODAY AS FRONT ARRIVES TONIGHT.
SHOWERS AND AREAS OF RAIN WILL CONTINUE TODAY FROM THE FIRST FRONT OF
THE BERING LOW...THEN TONIGHT WILL SEE HEAVIER AMOUNTS AND LARGER
COVERAGE AS THE SECOND AND STRONGER FRONT SPREADS OVER THE MAINLAND.
AS LOW PRESSURE AT ALL LEVELS IN THE BERING SETS UP SOUTHWESTERLY
FLOW OVER THE MAINLAND...EXPECT CONTINUED RAINY AND CLOUDY CONDITIONS
THROUGH THE WEEKEND.

SOUTHWEST ALASKA...AS THE STRONGER SECOND FRONT NEARS THE WESTERN
COAST TODAY...LOOK FOR WINDS TO BE INCREASING UP TO GALE FORCE ALONG
THE COASTS. THE CONTINUOUS SOUTHWESTERLY FLOW WILL NOT ONLY KEEP
SOUTHWESTERN ALASKA UNDER RAINY AND CLOUDY CONDITIONS BUT WILL ALSO
CAUSE SEAS TO SWELL ALONG THE COASTS UNDER A CONSTANT WIND FETCH. A
CLOSE EYE WILL BE KEPT ON THESE FOR WATCH/WARNING PURPOSES.

BERING AND ALEUTIANS...THE LARGE LOW WILL TRAVEL EAST ALONG THE CHAIN
THROUGH TONIGHT THEN WEAKEN AND LIFT OFF TO THE NORTH AS ANOTHER LOW
DROPS DOWN FROM RUSSIA TO FORM A LOW COMPLEX. FORMER TYPHOON FITOW
WILL ENTER INTO THE COMPLEX TO STRENGTHEN THE LOW STARTING MONDAY AND
BRING MAX GALES AND POSSIBLE MIN STORMS TO THE AREA.

.LONG TERM FORECAST...
THE OVERALL UPPER LEVEL PATTERN OF A LOW IN THE BERING AND A RIDGE
OVER EASTERN ALASKA LOOKS TO HOLD ON THROUGH MOST OF NEXT
WEEK...CONTINUING THE MOIST SOUTHWESTERLY FLOW OVER THE MAINLAND AND
EASTERN AND CENTRAL BERING.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...NONE
MARINE...GALE 120 130 132 150 160 165 170 175 176 180
FIRE WEATHER...NONE

LR SEP 07