Small Craft Advisory 376, NWS Anchorage, AK

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
1254 PM AKDT THU MAY 8 2014

.ANALYSIS AND UPPER LEVELS...
THE UPPER LEVEL RIDGE OVER THE EASTERN BERING SEA AND SOUTHWEST
ALASKA CONTINUES TO BUILD INTO THE STATE. WHILE THE UPPER LEVEL
LOW IN THE SOUTHEAST GULF OF ALASKA IS MOVING EASTWARD AND OUT OF
THE AREA IT STILL HAD ENOUGH PUNCH LEFT TO PUSH A SHORT WAVE INTO
THE NORTHERN GULF LATE LAST NIGHT THROUGH TODAY. FARTHER WEST A
LONGWAVE TROUGH IS SERVING AS A CATALYST FOR A LOW COMPLEX IN THE
FAR WESTERN BERING SEA. THIS IS ALSO BRINGING A FRONTAL ZONE INTO
THE WESTERN AND CENTRAL BERING SEA WITH SOUTHWEST FLOW BOTH ALOFT
AND AT THE SURFACE. ANOTHER SURFACE FEATURE OF NOTE IS A TROUGH
ALONG THE NORTH GULF COAST. THIS TROUGH IS EXPECTED TO DEVELOP
INTO A CLOSED LOW BY TOMORROW BUT THERE IS STILL A LITTLE
UNCERTAINTY AS TO HOW STRONG IT WILL BE.
&&

.MODEL DISCUSSION...
IN HINDSIGHT THE MODELS UNDERESTIMATED THE STRENGTH OF THE
SHORT WAVE THAT MOVED ACROSS THE NORTHERN GULF LATE LAST NIGHT
INTO TODAY. THE NAM WAS THE BEST OF THE BUNCH BUT IT WAS A LITTLE
TOO WEAK AS WELL. THE GOOD NEWS IS THAT THE MODELS DID FINALLY
INITIALIZE IT ON THE 12Z RUNS AND SEEM TO HAVE A MUCH BETTER
HANDLE ON IT. GOING FORWARD THE BIGGEST QUESTION WILL BE HOW THE
TROUGH IN THE NORTHERN GULF DEVELOPS INTO A CLOSED LOW. MODELS ALL
SHOW THAT HAPPENING JUST EAST OF MIDDLETON ISLAND WHICH WILL
CREATE GUSTY OFFSHORE WINDS ALONG THE ENTIRE NORTH GULF COAST.
PAST MODEL RUNS WERE MORE SCATTERED IN WHERE THEY RESOLVED THE
LOCATION OF THIS FEATURE BUT THEY SEEM TO HAVE SETTLED ON A COMMON
SOLUTION. THE STRENGTH IS STILL IN QUESTION AND WILL HAVE AN
IMPACT TO BOTH WINDS AND TEMPERATURES ALONG THE GULF COAST
TOMORROW.
&&

.SHORT TERM FORECAST...
SOUTHCENTRAL ALASKA...
AS STATED EARLIER THE SHORT WAVE IN THE NORTHERN GULF WAS STRONGER
THAN ANTICIPATED AND THAT BROUGHT SOME HIGHER WINDS AND MORE RAIN
THO THE REGION. THAT WAVE IS NOW WEAKENING AS THE RIDGE BUILDS
INTO THE AREA AND THAT WILL TAPER THE RAIN OFF INTO SCATTERED
SHOWERS OVERNIGHT. THE INLAND AREAS THAT HAVE NOT CLEARED OUT YET
SHOULD DO SO IN EARNEST BY FRIDAY. THE TROUGH IN THE NORTHERN GULF
IS A SUBTLE BUT IMPORTANT FEATURE. THIS TROUGH WILL BRING SOME
GUSTY OFFSHORE WINDS WHICH SHOULD OVERRIDE THE SEA BREEZE FROM
SEWARD THROUGH VALDEZ TOMORROW. THE KACHEMAK BAY SEA BREEZE LINES
UP WITH THE PRESSURE GRADIENT SO IT SHOULD BE STRONGER TOMORROW.
IN CONJUNCTION WITH THE OFFSHORE NORTHERLY WINDS THE TEMPERATURES
NEAR THE COAST WILL BE WELL INTO THE 60S WITHOUT THE SEA BREEZE TO
COOL THEM OFF. THE PRESSURE GRADIENT SHOULD BE WEAKER BY SATURDAY
AND DIMINISH THE WINDS BRINGING BACK TO SEA BREEZES TO THE NORTH
GULF COAST.

SOUTHWEST ALASKA...
EVEN WITH THE RIDGE BUILDING INTO THE AREA THERE IS A SHORT WAVE
TROUGH RIDING OVER THE TOP OF IT BRINGING IN SOME CLOUDS AND
SHOWERS TO THE KUSKOKWIM DELTA TODAY. THESE SHOULD CLEAR OUT
OVERNIGHT THOUGH THERE WILL REMAIN THE CHANCE OF LOW CLOUDS AND
FOG ALONG THE COAST. FARTHER EAST IN BRISTOL BAY AND THE KUSKOKWIM
VALLEY THERE WILL BE SOME CLOUDS THAT PASS THROUGH OVERNIGHT BUT
IT SHOULD CLEAR UP AGAIN TOMORROW.

BERING SEA/ALEUTIANS...
THE ORIENTATION OF THE RIDGE IN THE EASTERN BERING SEA AND THE LOW
COMPLEX IN THE WESTERN BERING SEA PUTS A FRONTAL ZONE AND STRONG
SOUTHWEST FLOW OVER THE CENTRAL BERING. THIS WILL KEEP THE CENTRAL
ALEUTIANS THROUGH THE PRIBILOF ISLANDS IN THE RAINFALL UNTIL
TOMORROW WHEN THE LOW WEAKENS AND THE RIDGE STRENGTHENS IN THE
EASTERN BERING SEA.
&&

.LONG TERM FORECAST...
SUNNY SKIES WILL CONTINUE INTO NEXT WEEK ACROSS MOST OF SOUTHERN
ALASKA AS HIGH PRESSURE REMAINS OVER THE MAINLAND PART OF THE
STATE. THIS WILL BRING BACK THE ABOVE NORMAL TEMPERATURES TO MOST
OF MAINLAND ALASKA.
&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...NONE.
FIRE WEATHER...NONE.
&&

MAY 14