Small Craft Advisory 337, NWS Anchorage, AK

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
140 PM AKDT TUE APR 16 2013

.ANALYSIS AND UPPER LEVELS...
THE OVERALL WEATHER PATTERN REMAINS VERY SIMILAR TO PREVIOUS DAYS. A
COLD CORE UPPER LOW REMAINS NEARLY STATIONARY OVER THE TALKEETNA
MOUNTAINS. MEANWHILE...A SURFACE LOW IS MOVING THROUGH THE SOUTHERN
GULF AND IS HEADED TOWARD THE NORTHERN PANHANDLE. SOUTHWEST FLOW
ALOFT HAS ALLOWED THIS LOW TO SPREAD MOISTURE ALL THE WAY INTO FAR
EASTERN PRINCE WILLIAM SOUND...WHERE VALDEZ AND CORDOVA HAVE SEEN
SEVERAL INCHES OF HEAVY WET SNOW ACCUMULATE SINCE EARLY THIS MORNING.
OUT WEST...A COMPLEX LOW REMAINS SOUTH OF THE ALEUTIANS...WITH
MULTIPLE WEAK DISTURBANCES PINWHEELING AROUND AND AFFECTING MUCH OF
THE SOUTHERN BERING SEA WITH GUSTY WINDS AND LIGHT TO MODERATE
PRECIPITATION.

.MODEL DISCUSSION...
MODELS ARE IN OVERALL EXCELLENT AGREEMENT ON THE EVOLUTION OF THE
MAJOR FEATURES THROUGH THE UPCOMING WEEKEND. THE UPPER LOW OVER
SOUTHCENTRAL WILL FINALLY KICK OUT TO THE EAST LATE
WEDNESDAY...GIVING WAY TO HIGH PRESSURE BUILDING IN FROM THE NORTH.
MEANWHILE...THE COMPLEX LOW SOUTH OF THE ALEUTIANS WILL SLOWLY LOSE
STRENGTH AND DRIFT TO THE EAST THROUGH THE WEEKEND...ALLOWING ALL
PARTS OF THE FORECAST DOMAIN TO EXPERIENCE RELATIVELY BENIGN WEATHER
BY LATE THIS WEEK. THE NAM WAS THE MODEL OF CHOICE TODAY...DUE ALMOST
EXCLUSIVELY TO ITS SUPERIOR MODELING OF SMALL-SCALE GAP WINDS THROUGH
COMPLEX TERRAIN.

.SHORT TERM FORECAST...
SOUTHCENTRAL...STEADY SNOW WILL COME TO AN END THIS AFTERNOON FROM
THE COPPER BASIN TO VALDEZ AND CORDOVA AS THE ASSOCIATED GULF LOW
CONTINUES TO TRACK INTO THE PANHANDLE. TO THE WEST...AMPLE SUNSHINE
WILL ALLOW DIURNAL CONVECTION TO DEVELOP AGAIN TODAY...PRIMARILY OVER
THE TALKEETNA MOUNTAINS AND MATANUSKA VALLEY. THIS TREND WILL
CONTINUE AGAIN WEDNESDAY...AS COLD AIR ALOFT ASSOCIATED WITH THE
UPPER LOW GENERATES STEEP LAPSE RATES ACROSS MOST INTERIOR LOCATIONS.
BY THURSDAY...HIGH PRESSURE MOVES IN ALOFT AND AT THE SURFACE...AND
SHOULD SPREAD WIDESPREAD SUN TO THE ENTIRE AREA WITH NEAR-NORMAL
TEMPERATURES.

SOUTHWEST MAINLAND...CLEAR SKIES AND OFFSHORE WINDS WILL CONTINUE
THROUGH THE END OF THE WEEK. TEMPERATURES WILL SLOWLY WARM...WITH A
CHANCE OF AFTERNOON/EVENING SNOW SHOWERS CONFINED MAINLY TO THE
EASTERN KUSKOKWIM VALLEY THROUGH WEDNESDAY.

BERING SEA AND ALEUTIANS...GUSTY EASTERLY WINDS AND RAIN WILL
GRADUALLY SUBSIDE THROUGH FRIDAY AS THE COMPLEX LOW TO THE SOUTH
WEAKENS. HIGH PRESSURE AND SLIGHTLY WARMER TEMPERATURES WILL
GRADUALLY BUILD BACK IN FOR THE WEEKEND...WITH LIGHT NORTHEAST FLOW
CONTINUING ACROSS MOST OF THE REGION.

.LONG TERM FORECAST...
AFTER A WARM-UP TO NEAR NORMAL TEMPERATURES THIS WEEKEND...LONG RANGE
MODELS ARE SUGGESTING YET ANOTHER COLD UPPER TROUGH WILL DROP BACK
INTO THE MAINLAND NEXT WEEK. THIS WILL LIKELY KEEP OUR TEMPERATURES
BELOW NORMAL...WITH MOST OF THE ACTIVE WEATHER STAYING SOUTH OF THE
STATE.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...NONE
MARINE...GALE 155 170 176 411 412 413 414
FIRE WEATHER...NONE

DIXON APR 13