Small Craft Advisory 9, NWS Fairbanks, AK

NORTHERN ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FAIRBANKS AK
332 AM AKDT SUN MAY 10 2015

.DISCUSSION...
CURRENT MODELS RUNS CONTINUE TO BE IN GOOD AGREEMENT OUT THROUGH
72 HOURS FOR THE MAJOR FEATURES AFFECTING NORTHERN ALASKA...WITH
GOOD CONTINUITY WITH THE PRECEDING RUNS.

UPPER AIR...
AT 500 MB...UPPER RIDGE LOBE EXTENDS ACROSS THE CENTRAL AND
EASTERN BROOKS RANGE THEN CURVING SOUTHWARD ACROSS THE WESTERN
INTERIOR TO BRISTOL BAY. THIS SECONDARY LOB WILL MOVE NORTHEAST
THROUGH 4 AM SUN...BECOMING IN PHASE WITH THE MAIN RIDGE OVER
NORTHWEST CANADA. SOME WEAK RIDGING WILL REMAIN OVER THE
WESTERN INTERIOR AND INLAND WEST COAST AREAS THROUGH MON
NIGHT.

A 538 DAM LOW CENTERED NEAR 57N/148W IN THE GULF OF ALASKA WILL
WEAKEN TO A 542 DAM CENTER OVER PRINCE WILLIAM SOUND BY 10 AM MON.
A SHORT WAVE TROUGH ROTATING AROUND THE UPPER LOW WILL MOVE
NORTHWARD TO EXTEND FROM THE NORTHWAY AREA EASTWARD INTO THE
YUKON TERRITORY BY 10 AM MON...THEN CONTINUE NORTH NORTHEASTWARD
TO THE MACKENZIE RIVER DELTA AREA BY 10 PM MON. A BROAD WEAK
TROUGH OF LOW PRESSURE WILL REMAIN ACROSS THE EASTERN INTERIOR.

A SHORT WAVE TROUGH NOW OVER THE WESTERN ALEUTIANS WILL MOVE
NORTHEASTWARD TO EXTEND FROM THE GULF OF ANADYR TO THE YUKON
RIVER DELTA AREA BY 10 AM TUE. NO SURFACE SYSTEM IS ASSOCIATED
WITH THIS SHORT WAVE.

SURFACE...
A LOW PRESSURE TROUGH CURRENTLY EXTENDS ON A LINE ANVIK-RUBY-FT
YUKON AND EASTWARD INTO THE YUKON TERRITORY. THIS TROUGH WILL
GRADUALLY WEAKEN THROUGH 4 AM MON.

A 1018 MB HIGH PRESSURE RIDGE ALONG THE ARCTIC COAST WILL MOVE
SLOWLY NORTHWARD INTO THE BEAUFORT SEA THROUGH MON...BUILDING
TO ABOUT 1023 MB.

A 998 MB LOW CENTERED NEAR 60N/175W IN THE BERING SEA WILL
WEAKEN TO A 1010 MB CENTER OVER THE GULF OF ANADYR BY 10 AM TUE.

A WEAK 1009 MB LOW WILL DEVELOP NEAR 70N/173W IN THE CHUKCHI
SEA AROUND 4 PM MON...THEN TRACK EASTWARD ACROSS THE BEAUFORT
SEA THROUGH WED EVENING. PROJECTED POSITION AT 10 PM WED IS ABOUT
75N/130W. NAM/GFS PROGS AGREE WELL ON TRACK AND CENTRAL PRESSURE
OF THIS LOW.

INTERIOR...
RAIN WILL CONTINUE OVER MUCH OF THE CENTRAL INTERIOR TODAY...
WITH SOMEWHAT LESS AREA COVERAGE TONIGHT AND MON. THE HEAVIEST
RAINFALL AMOUNTS...UP TO 1-1.5 INCHES...ARE EXPECTED TO BE ZONE
221 AND NEARBY AREAS OF ZONES 216 AND 219. CONVECTIVE SHOWERS
ARE EXPECTED OVER PARTS OF THE CENTRAL AND EASTERN INTERIOR
MON AFTERNOON AND EVENING...THE MOST ACTIVE AREAS ARE EXPECTED
TO BE IN ZONES 220 AND 224. CONVECTIVE ACTIVITY TUE WILL BE VERY
SPOTTY AND ONLY IN THE CENTRAL INTERIOR. FOR WED...ISOLATED
AFTERNOON AND EVENING THUNDERSTORMS POSSIBLE OVER THE NORTHEAST
INTERIOR.

ARCTIC COAST...
EAST TO NORTHEAST WIND FLOW IS EXPECTED TO CONTINUE ON THE ARCTIC
COAST THROUGH SUN NIGHT...WITH AREAS OF FOG AT NIGHT. BY MON
NIGHT...WINDS ARE EXPECTED TO BECOME WESTERLY OVER THE CENTRAL
AND EASTERN ARCTIC COAST...AND SOUTH TO SOUTHWEST OVER THE
WESTERN ARCTIC COAST.

WEST COAST...
A CHANCE OF RAIN OVER ST LAWRENCE ISLAND SUN AND SUN NIGHT...
AND ON THE BERING STRAIT COAST SUN NIGHT. ISOLATED SHOWERS
POSSIBLE OVER THE YUKON DELTA MON AFTERNOON AND EVENING.

&&

.FIRE WEATHER...
SOUTHERLY GAP WINDS IN AND NEAR ISABEL PASS ARE EXPECTED
TO DIMINISH GRADUALLY...BECOMING LIGHT BY SUN EVENING.
MIN RH THIS AFTERNOON IS NOT EXPECTED TO GET LOW ENOUGH
FOR RED FLAGS. NO ISSUES OVER THE CENTRAL INTERIOR TODAY
DUE TO WETTING RAINS AND HIGHER HUMIDITIES. SOME DRYING EXPECTED
MON THROUGH WED BUT MIN RH IS NOT EXPECTED TO BE LESS THAN 30
PERCENT. ISOLATED THUNDERSTORMS EXPECTED IN PARTS OF THE CENTRAL
INTERIOR MON AFTERNOON AND EVENING...WITH THE BEST ACTIVITY IN
ZONES 220 AND 224. ONLY SPOTTY CONVECTIVE ACTIVITY IN THE CENTRAL
INTERIOR IS EXPECTED TUE. ISOLATED THUNDERSTORMS EXPECTED IN THE
NORTHEAST INTERIOR WED AFTERNOON AND EVENING.

&&

.HYDROLOGY...
A QUIET RIVER BREAKUP CONTINUES. ICE WAS REPORTED TO BE MOVING
ON THE YUKON RIVER AT GALENA YESTERDAY...WITH A RUN OF ICE MOVING
DOWN THE RIVER AT TANANA.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY FOR PKZ210.
&&

RF MAY 15