Small Craft Advisory 142, NWS Anchorage, AK

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
436 PM AKST SAT FEB 14 2015

.ANALYSIS AND UPPER LEVELS...
SOUTHERLY FLOW CAUSED BY A LOW NEAR THE SOUTHERN END OF THE KENAI
PENINSULA IS BRINGING PRECIPITATION TO THE NORTHERN GULF
COAST...KODIAK ISLAND AND SOUTHCENTRAL. IT IS PRIMARILY RAIN BUT
IS TRANSITIONING TO SNOW FURTHER INLAND. NORTHEASTERLY FLOW IS
KEEPING MUCH OF THE PRECIPITATION OUT OF THE SOUTHWEST BUT A LOW
SOUTH OF THE EASTERN ALEUTIANS IS KEEPING CLOUD COVER AND
PRECIPITATION FOR THE ISLANDS AND THE ALASKA PENINSULA.

&&

.MODEL DISCUSSION...
THE MODELS ARE IN GOOD AGREEMENT IN THE SHORT TERM. SOME
DISCREPANCIES DO ARISE WITH THE NEXT PACIFIC LOW MOVING TOWARDS
THE ALEUTIANS ON SUNDAY. THE GFS IS SLOWER THAN THE OTHER MODELS
WHILE THE GEM IS SLIGHTLY MORE TO THE EAST.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (DAYS 1 AND 2)...

RAIN WILL CONTINUE TO DEVELOP ALONG THE SURFACE LOW IN THE
NORTHERN GULF TONIGHT BRINGING PERIODS OF RAIN TO COASTAL AREAS
WITH SCATTERED RAIN AND SNOW SHOWERS WORKING INLAND AS A STRONGER
UPPER SHORTWAVE PUSHES OVERHEAD LATE TONIGHT. TEMPERATURES DROP
TO NEAR FREEZING OR BELOW AFTER SUNSET ACROSS MUCH OF SOUTHCENTRAL.
WITH A WARMER AIR MASS JUST OFF THE SURFACE...THERE WILL BE A
SLIGHT CHANCE FOR FREEZING RAIN FROM THE ANCHORAGE BOWL AND NORTH
TO THE SUSITNA VALLEY TONIGHT AND TOMORROW MORNING. IN
ADDITION...STRONG WINDS INCREASE ACROSS THE TURNAGAIN ARM AND
PORTAGE VALLEY DURING THE EVENING AS THE SURFACE LOW CURRENTLY IN
THE GULF MOVES TO THE SOUTHERN KENAI. THIS LOW WEAKENS SUNDAY
MORNING AND WINDS TAPER OFF. HOWEVER THE WINDS INCREASE AGAIN
SUNDAY EVENING AS THE NEXT LOW MOVES UP FROM THE SOUTHERN GULF.

THE NEXT STRONG STORM SYSTEM IS DEVELOPING SOUTH OF KODIAK ISLAND
AND MOVES INTO THE SOUTHERN GULF EARLY TOMORROW MORNING. STORM
FORCE WINDS ARE EXPECTED AROUND THE CORE OF THIS SYSTEM. THIS
STORM WILL BE A FAST MOVING SYSTEM MAKING IT TO THE NORTHERN GULF
BY SUNDAY AFTERNOON. MODERATE TO HEAVY RAINFALL IS EXPECTED ALONG
THE FRONT WITH THE HIGHEST ACCUMULATIONS ALONG EASTERN KENAI AND
PRINCE WILLIAM SOUND. THE FRONT STALLS ALONG THE NORTHERN GULF
SUNDAY NIGHT WITH SCATTERED RAIN AND SNOW SHOWERS CONTINUING TO
PUSH INLAND AS AN OVERRUNNING WARMER AIR MASS GLIDES TOWARD THE
CENTRAL MAINLAND. GAP WINDS WILL INCREASE ALONG THE COAST SUNDAY
NIGHT INTO MONDAY.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (DAYS 1 AND 2)...

MOISTURE ASSOCIATED WITH THE LOW DECAYING WEST OF COOK INLET WILL
SPREAD SOME SNOW SHOWERS ACROSS THE ALEUTIAN AND ALASKA RANGES
TONIGHT. WITH WARMER AIR ALOFT AND COLD AIR TRAPPED AT THE
SURFACE...A SLIGHT CHANCE OF FREEZING RAIN IS POSSIBLE NEAR THE
ALEUTIAN RANGE TONIGHT AND SUNDAY MORNING. A SIGNIFICANT FRONT
FROM NORTH PACIFIC WILL AFFECT THE REGION SUN AND MON. WARMER AIR
WILL WORK ITS WAY TO THE SURFACE IN THE BRISTOL BAY ZONE LATER ON
SUN WITH A MIX OF RAIN AND SNOW...AND SUN NIGHT SNOW WILL SPREAD
INTO THE KUSKOKWIM DELTA WITH A THREAT OF FREEZING RAIN SOUTHEAST
OF BETHEL. THIS THREAT WILL MOVE OVER THE ENTIRE ZONE ON MONDAY.
STRONG WIND WILL ALSO DEVELOP THROUGH CHANNELED TERRAIN OF THE
BRISTOL BAY ZONE SUN INTO MON.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (DAYS 1 AND 2)...

A DECAYING LOW NEAR THE CENTRAL ALEUTIANS WILL BRING A MIX OF RAIN
AND SNOW AND SOME WIND TO THAT AREA AND THE PRIBILOFS TONIGHT.
THE NEXT NORTH PACIFIC LOW WILL BRING A STRONG FRONT WITH STORM
FORCE WINDS AND MAINLY RAIN TO THE AKPEN AND THE EASTERN AND
CENTRAL ALEUTIANS SUN INTO MON. RAIN AND SNOW SHOWERS ARE EXPECTED
OVER THE WESTERN ALEUTIANS.

&&

.LONG TERM FORECAST (DAYS 3 THROUGH 7)...
AN ACTIVE PATTERN CHARACTERIZED BY ABUNDANT PRECIPITATION AND
ABOVE NORMAL TEMPERATURES LOOKS TO CONTINUE INTO NEXT WEEKEND IN
THE WAKE OF THE NORTH PACIFIC LOW MOVING INTO THE EASTERN BERING
AND THE ASSOCIATED STRONG FRONT TRACKING TOWARDS THE GULF COAST
EARLY IN THE WEEK. A BROAD UPPER LEVEL RIDGE WILL REMAIN
ENTRENCHED OVER THE WEST COAST OF NORTH AMERICA...KEEPING THE
ALASKAN MAINLAND UNDER THE INFLUENCE OF BROAD SOUTHERLY FLOW AND
ALLOWING A SERIES OF DISTURBANCES TO TRACK TOWARDS THE GULF FROM
THE NORTH PACIFIC. THIS WILL KEEP THE BULK OF THE PRECIPITATION
FOCUSED ALONG THE GULF COAST...WITH DOWNSLOPE DRYING CONTRIBUTING
TO A MORE SPORADIC AND SHOWERY REGIME OVER INLAND AREAS. THE
BERING WILL ALSO REMAIN IN A GENERALLY SHOWERY PATTERN BENEATH
BROAD CYCLONIC FLOW EXTENDING FROM EASTERN RUSSIA WELL INTO THE
NORTH PACIFIC.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...STORM 119 120 130 131 132 138 150 155
         GALE 136 137 139 141 160 165 170 172 179 180
         HEAVY FREEZING SPRAY 185
FIRE WEATHER...NONE.

&&

SYNOPSIS AND MODEL DISCUSSION...DK
SOUTHCENTRAL ALASKA...KH
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...DS
LONG TERM...CB