Small Craft Advisory 587, NWS Anchorage, AK

887 
FZAK51 PAFC 202352
CWFAER

COASTAL WATERS FORECAST
NATIONAL WEATHER SERVICE ANCHORAGE ALASKA
400 PM AKDT SAT AUG 20 2011

COASTAL WATERS FORECAST FOR THE NORTHERN GULF OF ALASKA COAST
UP TO 100 NM OUT INCLUDING KODIAK ISLAND AND COOK INLET.

WIND FORECASTS REFLECT THE PREDOMINANT SPEED AND DIRECTION
EXPECTED. SEA FORECASTS REPRESENT AN AVERAGE OF THE HIGHEST
ONE-THIRD OF THE COMBINED WIND WAVE AND SWELL HEIGHT.

PKZ197-211500-
400 PM AKDT SAT AUG 20 2011
.SYNOPSIS FOR THE NORTH GULF COAST+KODIAK ISLAND WATERS+
COOK INLET...
A 986 MB LOW 120 NM SOUTHEAST OF KODIAK CITY WILL MOVE TO 250 NM 
EAST OF KODIAK CITY LATE SUN MORNING AND THEN REMAIN NEARLY
STATIONARY AS IT WEAKENS THROUGH MON.
$$

PKZ120-211500-
CAPE SUCKLING TO GORE POINT
400 PM AKDT SAT AUG 20 2011

...SMALL CRAFT ADVISORY TONIGHT...

.TONIGHT...SE WIND 15 KT. SEAS 8 FT. PATCHY FOG. RAIN.
.SUN AND SUN NIGHT...VARIABLE WIND 10 KT. SEAS 7 FT. PATCHY FOG. 
.MON...NE WIND 15 KT. SEAS 6 FT. 
.MON NIGHT...VARIABLE WIND 10 KT. SEAS 5 FT. 
.TUE...SE WIND 15 KT. SEAS 5 FT. 
.WED...SE WIND 20 KT. SEAS 5 FT. 
.THU...E WIND 30 KT. SEAS 7 FT.  

$$

PKZ121-211500-
RESURRECTION BAY
400 PM AKDT SAT AUG 20 2011

.TONIGHT...S WIND 10 KT IN THE EVENING BECOMING VARIABLE LESS THAN
10 KT. SEAS 2 FT. HIGHER SEAS S OF CAINES HEAD. PATCHY FOG. RAIN.
.SUN...VARIABLE WIND LESS THAN 10 KT BECOMING S 10 KT IN THE
AFTERNOON. SEAS 2 FT. PATCHY FOG. RAIN SHOWERS. 
.SUN NIGHT...VARIABLE WIND LESS THAN 10 KT. SEAS 1 FT. PATCHY FOG. 
.MON...S WIND 10 KT. SEAS 2 FT. 
.MON NIGHT...VARIABLE WIND LESS THAN 10 KT. SEAS 1 FT. 
.TUE AND WED...VARIABLE WIND 10 KT. SEAS 2 FT.  
.THU...N WIND 15 KT. SEAS 3 FT.  

$$

PKZ125-211500-
PRINCE WILLIAM SOUND
400 PM AKDT SAT AUG 20 2011

.TONIGHT...E WIND 15 KT BECOMING VARIABLE 10 KT AFTER MIDNIGHT. 
SEAS 2 FT. PATCHY FOG. RAIN.
.SUN AND SUN NIGHT...VARIABLE WIND LESS THAN 10 KT. SEAS LESS 
THAN 2 FT. SHOWERS AND PATCHY FOG.  
.MON AND MON NIGHT...VARIABLE WIND 10 KT. SEAS 2 FT. 
.TUE...E WIND 15 KT. SEAS 3 FT. 
.WED...SE WIND 10 KT. SEAS 2 FT. 
.THU...E WIND 15 KT. SEAS 3 FT.  

$$

PKZ129-211500-
PASSAGE CANAL
400 PM AKDT SAT AUG 20 2011

.TONIGHT...E WIND 15 KT DIMINISHING TO E WIND LESS THAN 10 KT 
DURING THE EVENING. SEAS 2 FT OR LESS. PATCHY FOG. RAIN.
.SUN AND SUN NIGHT...VARIABLE WIND LESS THAN 10 KT. SEAS 1 FT. 
SHOWERS AND PATCHY FOG.  
.MON THROUGH WED...E WIND 10 KT OR LESS. SEAS 2 FT OR LESS. 
.THU...E WIND 15 KT. SEAS 2 FT.  

$$

PKZ130-211500-
BARREN ISLANDS AND KAMISHAK BAY WATERS
400 PM AKDT SAT AUG 20 2011

.TONIGHT...VARIABLE WIND 10 KT. SEAS 7 FT. PATCHY FOG. RAIN.
.SUN AND SUN NIGHT...VARIABLE WIND 10 KT. SEAS 5 FT. PATCHY FOG. 
.MON...SW WIND 10 KT. SEAS 4 FT. 
.MON NIGHT AND TUE...W WIND 25 KT. SEAS 5 FT. 
.WED...SE WIND 20 KT. SEAS 5 FT. 
.THU...E WIND 25 KT. SEAS 5 FT.  

$$

PKZ132-211500-
SHUYAK ISLAND TO SITKINAK
400 PM AKDT SAT AUG 20 2011

...SMALL CRAFT ADVISORY TONIGHT...

.TONIGHT...W WIND 15 KT. SEAS 8 FT. PATCHY FOG. RAIN.
.SUN...VARIABLE WIND 10 KT. SEAS 7 FT. PATCHY FOG. 
.SUN NIGHT...W WIND 20 KT EXCEPT VARIABLE 10 KT N OF DANGEROUS CAPE.
SEAS 6 FT. 
.MON AND MON NIGHT...W WIND 25 KT. SEAS 6 FT. 
.TUE...W WIND 30 KT. SEAS 6 FT. 
.WED...SE WIND 20 KT. SEAS 7 FT. 
.THU...NE WIND 15 KT. SEAS 5 FT.  

$$

PKZ138-211500-
SHELIKOF STRAIT
400 PM AKDT SAT AUG 20 2011

...SMALL CRAFT ADVISORY SUNDAY NIGHT...

.TONIGHT...SW WIND 15 KT BECOMING VARIABLE LESS THAN 10 KT 
TOWARD MIDNIGHT. SEAS 2 FT. PATCHY FOG. 
.SUN...SW WIND 10 KT. SEAS 2 FT. PATCHY FOG. 
.SUN NIGHT...SW WIND 15 KT EXCEPT W WIND 25 KT SOUTH END OF STRAIT.
SEAS 4 FT. 
.MON...SW WIND 20 KT. SEAS 4 FT. 
.MON NIGHT...W WIND 25 KT. SEAS 4 FT. 
.TUE...SW WIND 20 KT. SEAS 5 FT. 
.WED...SE WIND 20 KT. SEAS 5 FT. 
.THU...NE WIND 20 KT. SEAS 5 FT.  

$$

PKZ140-211500-
COOK INLET NORTH OF KAMISHAK BAY AND ENGLISH BAY
400 PM AKDT SAT AUG 20 2011

.TONIGHT...SW WIND 10 KT. SEAS 2 FT. PATCHY FOG. 
.SUN...SW WIND 10 KT INCREASING TO 15 KT IN THE AFTERNOON. 
SEAS 3 FT. PATCHY FOG. 
.SUN NIGHT THROUGH TUE...S WIND 15 KT. SEAS 4 FT. 
.WED...SE WIND 15 KT. SEAS 3 FT. 
.THU...E WIND 15 KT. SEAS 3 FT.  

$$

PKZ141-211500-
KACHEMAK BAY
400 PM AKDT SAT AUG 20 2011

.TONIGHT...VARIABLE WIND LESS THAN 10 KT. SEAS 1 FT. PATCHY FOG. 
RAIN SHOWERS. 
.SUN...VARIABLE WIND LESS THAN 10 KT BECOMING SW 15 KT IN THE
AFTERNOON. SEAS BUILDING TO 3 FT. PATCHY FOG. 
.SUN NIGHT...S WIND 15 KT DIMINISHING TO 10 KT AFTER MIDNIGHT. 
SEAS 2 FT. 
.MON THROUGH TUE...SW WIND 15 KT. SEAS 4 FT. 
.WED...SE WIND 15 KT. SEAS 2 FT. 
.THU...E WIND 15 KT. SEAS 2 FT.  

$$

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
515 AM AKDT SAT AUG 20 2011

.ANALYSIS AND UPPER LEVELS...
THE DOMINANT WEATHER FEATURE THIS MORNING IS THE FILLING LOW NEAR
HOMER IN SOUTHERN COOK INLET. AN ASSOCIATED FRONT HAS MOVED ASHORE
THE NORTHERN GULF COAST...BUT RAIN IS STILL FALLING ACROSS
SOUTHCENTRAL AK SUPPORTED BY EMBEDDED SHORTWAVES ALOFT AND ONSHORE
FLOW. OVERALL...PRECIPITATION INTENSITY HAS EBBED...AND WINDS ARE
SLOWLY DIMINISHING IN THE FRONT'S WAKE AS THE PRESSURE GRADIENT
WEAKENS. FURTHER WEST...A DEFORMATION ZONE IS DRAPED OVER THE
SOUTHWEST MAINLAND WITH LIGHT RAIN FALLING THERE AS WELL. FAIR
WEATHER EXISTS ACROSS THE BERING/ALEUTIANS...WITH SOME PASSING
SHOWERS.

.MODEL DISCUSSION...
MODELS ACCEPTABLY CAPTURE THE MAIN WEATHER FEATURES IN THE
AOR...THOUGH THE NAM WAS GENERALLY PREFERRED FOR A BETTER CAPTURE OF
SUBTLE DETAILS IN THE FLOW. THE MORE SUBSTANTIAL DIFFERENCES ARISE
MONDAY THROUGH MID-NEXT WEEK AS AN UPPER-LOW DROPS DOWN FROM EASTERN
SIBERIA TOWARDS THE SOUTHWEST MAINLAND. THE GFS KEEPS THE PARENT LOW
OVER NORTHWESTERN AK AND DRAGS A STRONG SHORTWAVE THROUGH THE
SOUTHWEST AND SOUTHCENTRAL MAINLAND. THE ECMWF TENDS TO DIP THE
PARENT LOW FURTHER SOUTH TOWARDS BRISTOL BAY. AT THE SURFACE...THE
GFS IS ALSO CONSIDERABLY STROGNER THAN THE OTHER MODELS WITH A LOW
THAT MOVES INTO THE NORTHERN AND CENTRAL BERING. AS SUCH...FORECASTS
TRENDED HEAVY TOWARDS HPC GUIDANCE DUE TO THE UNCERTAINTY IN THE MID
TO LONG RANGE PERIODS.

.SHORT TERM FORECAST...
SOUTHCENTRAL...
RADAR DEPICTS STEADY RAINS ACROSS THE KENAI PENINSULA WHICH IS
CLOSEST TO THE WEAKENING LOW PRESSURE SYSTEM...AND PRINCE WILLIAM
SOUND WHERE ONSHORE FLOW IS THE STRONGEST. LOOK FOR PRECIPITATION IN
THESE AREAS TO BECOME LESS WIDESPREAD AS THE SURFACE LOW DISSIPATES
LATE TONIGHT AND ONSHORE FLOW WEAKENS. IN THE WAKE OF THE
FRONT...LOOK FOR SOME TURNAGAIN ARM WINDS TO BE DRAGGED INTO THE
SOUTH AND WEST PARTS OF THE ANCHORAGE BOWL TODAY...WITH THE
DOWNSLOPING TENDING TO RETARD PRECIPITATION MOVING UP FROM THE SOUTH
TO BRIEF PERIODS OF LIGHT RAIN OR SHOWERS. THE WEAKENING PARENT
UPPER-LOW OVER COOK INLET WILL SLIP EAST TO THE NORTHERN GULF AND
OPEN INTO A TROUGH SUNDAY AND MONDAY...WITH THE RESIDUAL INSTABILITY
ALOFT STILL KEEPING THINGS CLOUDY ACROSS SOUTHCENTRAL AK WITH THE
RISK OF SHOWERS.

SOUTHWEST...
RAIN WILL TAPER TO SHOWERS AS THE AFOREMENTIONED LOW WEAKENS AND
DRIFTS EAST THROUGH SUNDAY. IR SATELLITE DEPICTS THE LEADING EDGE OF
CLEARING FILTERING IN FROM THE NORTH AND WEST OVER COASTAL AREAS OF
THE THE KUSKOKWIM DELTA. THOUGH INITIALLY SLOW TO SCOUR OUT THE AMPLE
LOW-LVL MOISTURE...THIS AREA SHOULD EVENTUALLY NOSE TO THE SOUTH AND
EAST AND ALLOW FOR SOME BREAKS OF SUN ACROSS PORTIONS OF BRISTOL BAY
AS WELL BY MONDAY. THIS LOOKS TO BE RATHER TEMPORARY AS ANOTHER
SYSTEM DIPS DOWN FROM EASTERN SIBERIA WITH MORE CLOUDS AND INCREASING
CHANCES OF RAIN.

BERING SEA/ALEUTIANS...
BRISK NORTHWEST WINDS WILL PRODUCE GALE FORCE GUSTS THROUGH CHANNELED
TERRAIN ALONG THE SOUTHERN END OF THE APKPEN. LOOK FOR THESE
CONDITIONS TO SLOWLY WEAKEN SUNDAY...AS THE PRESSURE GRADIENT ALONG
THE WESTERN PERIPHERY OF THE MAINLAND LOW RELAXES. COOL DRY AIR ALSO
IS FILTERING DOWN FROM THE NORTHERN BERING...AND MAY LEAD TO A
REPRIEVE FROM THE TYPICAL STRATUS OVER THE PRIBILOFFS DOWN TOWARDS
THE AKPEN AND EASTERN CHAIN. THE NEXT SIGNIFICANT FEATURE WILL BE THE
LOW THAT DROPS DOWN FROM EASTERN RUSSIA INTO THE NORTHERN AND CENTRAL
BERING MONDAY INTO TUESDAY.

.LONG TERM FORECAST...
FORECAST CONFIDENCE IN THE EXTENDED PERIOD IS LOW DUE TO DIVERGING
MODEL SOLUTIONS. IT DOES APPEAR THOUGH THAT THE BULK OF THE
SIGNIFICANT WEATHER MID-LATE NEXT WEEK WILL BE BE FROM THE BERING TO
SOUTHWEST AK DUE TO PROXIMITY TO THE UPPER-LOW DROPPING DOWN FROM
EASTERN RUSSIA. SOUTHCENTRAL LOOKS TO INITIALLY REMAIN IN A SHOWERY
REGIME...THOUGH WILL NEED TO WATCH HOW MUCH ENERGY AND MOISTURE FROM
THE BERING SYSTEMS REACH THE AREA.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...NONE
MARINE...GALE...
FIRE WEATHER...NONE

JAM AUG 11