012
FGAK88 PACR 062243
RVSAK
AKZALL-220000-
HYDROLOGIC STATEMENT
NATIONAL WEATHER SERVICE ANCHORAGE AK
ALASKA-PACIFIC RIVER FORECAST CENTER
130 PM AST FRI NOV 6 2009
..RIVER AND LAKE ICE UNSAFE
THE NATIONAL WEATHER SERVICE HAS ISSUED A STATEMENT TO ADVISE THE
PUBLIC OF RIVER AND LAKE ICE THICKNESS THROUGH MOST OF ALASKA SOUTH
OF THE BROOKS RANGE. PEOPLE PLANNING TO USE RIVERS AND LAKES FOR
TRANSPORTATION OR RECREATION SHOULD CHECK THE THICKNESS AND
CONDITION OF THE ICE PRIOR TO USE. AT LEAST 4 INCHES OF ICE ARE
REQUIRED FOR A PERSON TO BE SAFE AND 6 INCHES FOR SNOW MACHINE USE.
RIVERS IN THE ALASKA INTERIOR HAVE ONLY RECENTLY FROZEN OVER AND THE
ICE IS LIKELY TOO THIN IN MANY LOCATIONS TO SUPPORT A SNOW MACHINE OR
A PERSON. LAKES IN SOUTHCENTRAL ALASKA HAVE ALSO RECENTLY DEVELOPED
A THIN ICE COVER AND ARE TOO THIN TO SAFELY SUPPORT SNOW MACHINE
TRAFFIC. RIVERS AND STREAMS IN SOUTHCENTRAL ALASKA ARE IN THE PROCESS
OF FREEZING UP AND MAY EXPERIENCE RISING WATER LEVELS DUE TO
CONSTRICTION OF THE CHANNEL CAUSED BY ICE FORMATION. WATER LEVELS MAY
RISE AND FLUCTUATE RAPIDLY DUE TO CHANGING ICE AND WEATHER CONDITIONS.
ALSO KEEP IN MIND THAT HEAVY SNOWFALL MAY BE SUFFICIENT TO DEPRESS ICE
AND CREATE OVERFLOW CONDITIONS.
THE NATIONAL WEATHER SERVICE IS ADVISING PEOPLE TO BE AWARE OF
THEIR SURROUNDINGS IF IT IS NECESSARY TO VENTURE OUT ONTO THE ICE.
KEEP IN MIND THAT VARIATIONS IN ICE THICKNESS OCCUR NATURALLY IN
RIVERS AND STREAMS AND THE THINNEST ICE ON LAKES IS NEAR THE INLETS
AND OUTLETS. WIND AND WARM TEMPERATURES AS WELL AS PRECIPITATION
SUCH AS SNOW AND RAIN ARE ALL FACTORS THAT CAN QUICKLY AFFECT ICE
STRENGTH AND THICKNESS. TRAVEL THAT MUST BE DONE SHOULD BE DONE
WITH EXTREME CAUTION.
THIS STATEMENT WILL BE NOT BE UPDATED.
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page