000
SRAK48 PACR 262302
RVAAK
AKZALL-232200-
ALASKA SPRING BREAKUP SUMMARY
NWS ALASKA PACIFIC RIVER FORECAST CENTER ANCHORAGE AK
4 PM AKDT May 26 2018
...SPRING BREAKUP SUMMARY FOR ALASKA....
FLOOD WARNING/WATCHES:
NONE AT THIS TIME.
ALASKA BREAKUP SUMMARY NOTABLE EVENTS FROM PAST 24 HOURS -
NO NEW INFORMATION SINCE YESTERDAY.
BREAKUP ON THE NORTH SLOPE IS PROCEEDING SLOWLY. TEMPERATURES ARE ON
THE COOL SIDE, WITH BELOW NORMAL TEMPERATURES AT SAGWON AND PRUDHOE
BAY, AND WATER LEVELS REMAIN LOW. WATER ON THE COLVILLE RIVER IS
BEGINING TO RISE ALONG THE LOWER REACH NEAR NUIQSUIT. CHANNEL ICE ON
THE COLVILLE RIVER IS STILL INTACT ALONG THE LOWER REACH. FLOW ON
THE SAG RIVER IS BEGINNING TO INCREASE BASED ON MANUAL MEASUREMENTS
AND WEBCAM IMAGERY.
STATEWIDE BREAKUP FLOOD POTENTIAL FORECAST-
BREAKUP IN ALASKA HAS COMPLETED WITH THE EXCEPTION OF THE NORTH
SLOPE. THE FLOOD POTENTIAL FROM SNOWMELT AND ICE JAMS THROUGHOUT
MOST OF ALASKA THIS SPRING WAS RATED AS LOW TO LOW-MODERATE
INDICATING THAT LOCATIONS THAT OFTEN EXPERIENCE FLOODING DURING
BREAKUP MAY HAVE SEEN MINOR FLOODING IF AN ICE JAM FORMED
DOWNSTREAM. THE CENTRAL TANANA VALLEY HAD A HIGHER RISK OF MINOR
FLOODING THIS SPRING DUE TO A GREATER THAN NORMAL WINTER SNOWPACK.
WEATHER - NORTH SLOPE TEMPERATURES ARE EXPECTED TO BE IN THE 30S FOR
THE NEXT FEW DAYS WITH A HIGH IN THE MID 40`S ON MEMORIAL DAY.
RECENT BREAKUP ACTIVITY ACROSS THE STATE:
********************************************************************
EVEN THOUGH A PARTICULAR RIVER OR REACH MAY BE DESCRIBED AS MOSTLY
OPEN OR OPEN... IT IS STILL POSSIBLE FOR RUNS OF ICE AND DEBRIS TO
MOVE THROUGH AS HEADWATERS UPSTREAM BREAKUP. PLEASE USE CAUTION AT
ALL TIMES WHEN ATTEMPTING TO NAVIGATE RIVERS.
*********************************************************************
SUSITNA RIVER... OPEN
SKWENTNA AND YENTNA RIVER.. OPEN
COPPER RIVER.. OPEN
TANANA RIVER.. OPEN
KUSKOKWIM... OPEN
YUKON RIVER... OPEN
KOYUKUK RIVER... OPEN
KOBUK RIVER... OPEN
NOATAK RIVER... OPEN
BROOKS RANGE - NORTH... (5/23) WATER ON THE COLVILLE RIVER IS STILL
MOSTLY ICE COVERED. BEGINING TO RISE ALONG THE LOWER REACH NEAR
NUIQSUIT. CHANNEL ICE ON THE COLVILLE RIVER IS STILL INTACK ALONG
THE LOWER REACH. FLOW ON THE SAG RIVER IS RISING BASED ON MANUAL
MEASUREMENTS.
(5/21) BASED ON PHOTOS FROM USGS AND WEBCAM IMAGES BREAKUP IS
BEGINNING ON THE NORTH SLOPE. SOME WATER HAS MOVED DOWN THE COLVILLE
AS FAR AS COLVILLE VILLAGE BUT SO FAR PROGRESS IS SLOW AND WATER
LEVELS ARE RELATIVELY LOW.
(5/20) WATER IS PROGRESSING ON TOP OF ICE TOWARDS THE ARCTIC OCEAN
ON THE NORTH SLOPE RIVERS SUCH AS THE COLVILLE AND KUPARUK. (5/16)
AN OPEN LEAD HAS FORMED ALONG THE SAGAVANIRKTOK RIVER ALONG THE
DALTON HIGHWAY.
FOR MORE DETAIL AND TO SEE A FLOOD POTENTIAL MAP REFER TO OUR WEB
SITE AT HTTPS://WWW.WEATHER.GOV/APRFC/FLOODPOTENTIAL
---------------------------------------------------------------------
SNOWMELT RUNOFF VOLUME: EXPECTED WATER VOLUME FROM SNOWMELT DURING
THE MELT SEASON.
FLOOD POTENTIAL: THE LIKELIHOOD OF FLOODING FROM SNOWMELT AND/OR
ICE JAMS. THIS IS INITIALLY CALCULATED BASED ON THE FLOOD FREQUENCY
FOR THE 2000 TO 2017 HISTORICAL RECORD AND ADJUSTED TO REFLECT
CURRENT CONDITIONS.
* AVERAGE (MEDIAN) BREAKUP DATES ARE FOR THE PERIOD 1980 THROUGH
2017 AND ARE CALCULATED FOR LOCATIONS WITH AT LEAST 5 YEARS OF DATA.
** ACTUAL BREAKUP DATE FOR THIS YEAR
---------------------------------------------------------------------
SNOWMELT FLOOD AVERAGE NO. OF FORECAST
RIVER - REACH RUNOFF POTENTIAL BREAKUP YEARS BREAKUP
VOLUME DATE* USED DATE
------------- ---------- --------- ------- ------ --------
SOUTHEAST PANHANDLE BELOW
KENAI RIVER BELOW LOW
ANCHOR RIVER BELOW LOW
MATANUSKA RIVER AVERAGE LOW
SUSITNA RIVER AVERAGE
GOLD CREEK LOW
SUNSHINE LOW 05/03 29 **05/04
YENTNA RIVER BELOW
LAKE CREEK LOW 05/01 27 **05/03
SKWENTNA RIVER BELOW
SKWENTNA LOW 04/30 23 **05/03
COPPER RIVER BASIN ABOVE AVERAGE
GAKONA RVR @ HWY LOW 04/30 30 **05/06
GULKANA RVR @ HWY LOW 04/30 29 **05/06
CHENA RIVER ABOVE AVERAGE
CHENA LAKES PROJECT
FAIRBANKS LOW 04/26 26
TANANA RIVER ABOVE AVERAGE
CHISANA @ NORTHWAY LOW 04/26 27 **04/25
SALCHA LOW
FAIRBANKS LOW 04/29 19 **04/27
NENANA LOW 04/30 38 **05/01
MANLEY LOW 05/03 27 **05/07
KUSKOKWIM RIVER AVERAGE
NIKOLAI LOW 04/23 32 **04/24
MCGRATH LOW-MOD 05/04 38 **05/09
STONY RIVER LOW 05/02 30 **05/02
SLEETMUTE LOW-MOD 05/02 29 **04/29
RED DEVIL LOW-MOD 05/04 32 **04/29
CROOKED CREEK LOW-MOD 05/05 32 **04/30
ANIAK LOW-MOD 05/07 35 **05/01
KALSKAG LOW 05/07 29 **05/05
TULUKSAK LOW 05/07 26 **05/04
AKIAK LOW 05/09 32 **05/04
KWETHLUK LOW-MOD 05/10 6 **04/30
BETHEL LOW 05/10 38 **05/03
NAPAKIAK LOW 05/11 23 **05/05
YUKON RIVER (UPPER) AVERAGE
DAWSON, YT LOW 05/04 38 **05/08
EAGLE LOW 05/04 37 **05/08
CIRCLE LOW-MOD 05/08 34 **05/10
FORT YUKON LOW 05/10 34 **05/11
BEAVER LOW 05/10 22 **05/12
STEVENS VILLAGE LOW 05/11 21 **05/11
RAMPART LOW 05/11 23 **05/12
YUKON RIVER (MIDDLE) ABOVE AVERAGE
TANANA LOW 05/08 33 **05/07
RUBY LOW 05/09 32 **05/12
GALENA LOW-MOD 05/11 37 **05/12
KOYUKUK LOW-MOD 05/10 13 **05/13
NULATO LOW-MOD 05/10 22 **05/13
KALTAG LOW 05/12 32 **05/14
ANVIK LOW 05/14 31 **05/15
YUKON RIVER (LOWER) ABOVE AVERAGE
HOLY CROSS LOW 05/15 31 **05/16
RUSSIAN MISSION LOW 05/16 32 **05/14
MARSHALL LOW-MOD 05/15 26 **05/15
PILOT STATION LOW 05/15 21 **05/13
MOUNTAIN VILLAGE LOW 05/19 31 **05/14
ALAKANUK/EMMONAK LOW-MOD 05/21 32 **05/18
KOYUKUK RIVER ABOVE AVERAGE
BETTLES LOW 05/09 36 **05/11
ALLAKAKET LOW 05/09 32 **05/11
HUGHES LOW-MOD 05/11 31 **05/11
SEWARD PENINSULA ABOVE AVERAGE
BUCKLAND LOW-MOD 05/20 28 **05/12
KOBUK RIVER ABOVE AVERAGE
KOBUK LOW-MOD 05/14 34 **05/11
SHUNGNAK LOW 05/17 28 **05/16
AMBLER LOW 05/17 34 **05/16
NOATAK RIVER ABOVE AVERAGE
NOATAK LOW 05/19 22 **05/15
BROOKS RANGE - NORTH AVERAGE
COLVILLE @ UMIAT LOW 05/25 18 05/23-05/29
COLVILLE @ COLVILLE VILLAGE LOW 06/03 20 05/31-06/05
SAGAVANIRKTOK RIVER AVERAGE
DALTON HWY LOW
THE NEXT SPRING BREAKUP SUMMARY IS SCHEDULED AT 2 PM AKDT Sunday,
MAY 27, 2018
$$
CVB
