Small Craft Advisory 54, NWS Fairbanks, AK

NORTHERN ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FAIRBANKS AK
1148 AM AKDT FRI AUG 17 2012

.DISCUSSION...
CURRENT GFS/NAM EUROPEAN RUNS AND THE GFS ENSEMBLE MEAN AGREE WELL
ON PROGGED SURFACE AND UPPER AIR PATTERNS OUT THROUGH SUNDAY. A
WET REGIME WILL CONTINUE OVER THE WEST COAST AND WESTERN INTERIOR.
A DEEPENING SHORT WAVE WITH ASSOCIATED 991 MB SURFACE LOW NEAR
57N/178E THIS MORNING WILL MOVE RAPIDLY EASTWARD TO BE JUST
NORTHWEST OF NUNIVAK ISLAND BY LATE SATURDAY MORNING. THE SHORT
WAVE WILL DEEPEN INTO A SUBSTANTIAL CLOSED UPPER LOW...534 TO 536
DAM AT 500 MB WITH THE SURFACE SYSTEM DEEPENING TO 984-985 MB.
BOTH THE SURFACE AND UPPER LOWS WILL MOVE TO NORTON SOUND BY LATE
SUNDAY MORNING AS THEY WEAKEN...BUT A SUBSTANTIAL SHORT WAVE
TROUGH WILL REMAIN...STRETCHING FROM THE SEWARD PENINSULA SOUTH TO
THE WESTERN ALASKA PENINSULA. THIS TROUGH WILL GRADUALLY WORK ITS
WAY EASTWARD INTO THE INTERIOR...EXTENDING FROM NORTHWEST ALASKA
TO THE KENAI PENINSULA BY LATE TUESDAY MORNING.

THE MOIST FLOW AND BROAD SCALE UPPER LIFT WITH THESE SYSTEMS WILL
PRODUCE WIDESPREAD SIGNIFICANT RAINFALL AMOUNTS OVER THE WEST
COAST...WESTERN INTERIOR...AND NORTHWEST ALASKA DURING THE NEXT 72
HOURS. THE WEST COAST...NORTHWEST ALASKA...AND THE NORTHWEST
INTERIOR SHOULD SEE WIDESPREAD ADDITIONAL RAINFALL AMOUNTS OF 1 TO
2 INCHES...WITH SOME LOCAL AMOUNTS OF 3 TO 4 INCHES POSSIBLE.
ELSEWHERE IN THE WESTERN INTERIOR...EXPECTED RAINFALL AMOUNTS ARE
MAINLY IN THE 0.5 TO 1.5 INCH RANGE...WITH HEAVIER AMOUNTS
POSSIBLE IN ZONE 215. A LULL IN THE RAINFALL MAY OCCUR MONDAY
NIGHT THROUGH MOST OF TUESDAY NIGHT...BUT ANOTHER PERIOD OF
SIGNIFICANT RAIN MAY OCCUR THURSDAY INTO FRIDAY. AT KIVALINA...THE
WATER LEVEL IN BOTH THE LAGOON AND ALONG THE SOUTH FACING SHORE
HAS DROPPED ABOUT 2 FEET SINCE LATE LAST NIGHT...WHEN IT WAS
REPORTED TO BE TOPPING THE SHORELINE AND UNDER A FEW HOUSES. THE
RED DOG TIDE GAGE INDICATES SEA LEVELS STILL ABOUT 1.7 FEET ABOVE
NORMAL...BUT SEA LEVELS ARE EXPECTED TO GRADUALLY RECEDE THROUGH
SUNDAY.

THE CENTRAL AND EASTERN INTERIOR SHOULD REMAIN MOSTLY DRY...
BUT SOME SHOWERS COULD OCCUR AT TIMES IN SOME AREAS.

COASTAL HAZARD POTENTIAL DAYS 3 AND 4...NONE.

&&

.FIRE WEATHER...
NO RED FLAGS EXPECTED.

&&

.HYDROLOGY...
THE WULIK RIVER BELOW TUTAK CREEK IS ABOUT 3 FEET BELOW
YESTERDAYS STAGE...BUT STILL ABOVE THE PREVIOUS RECORD
STAGE. CURRENT FLOW IS ABOUT 40,000 CFS...WELL ABOVE THE
MEDIAN FLOW OF AROUND 1500 CFS. THE FLOW AT THE CREST OVERNIGHT
WAS ESTIMATED AT ABOUT 70,000 CFS. ADDITIONAL CRESTS ARE POSSIBLE
WITH MORE RAIN EXPECTED...AT THE PRESENT TIME THERE IS A SLOW
RISE. THE FLOOD WARNING FOR ZONES 207-208 AND THE FLOOD WATCH FOR
ZONE 217 WILL BE EXTENDED FOR AN ADDITIONAL 24 HOURS. THERE ARE NO
GAGES ON THE KIVALINA RIVER...BUT IT IS LIKELY THAT THIS RIVER IS
ALSO RUNNING VERY HIGH.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...

FLOOD WARNING FOR AKZ207-AKZ208

FLOOD WATCH FOR AKZ217.

SMALL CRAFT ADVISORY FOR PKZ200-PKZ210.
&&

RF AUG 12