The National Weather Service (NWS) is the agency designated to determine flood stages for the rivers in Washington.

In general, the term flood stage is defined as the gage height of the lowest bank of the reach in which the gage is situated. The term "lowest bank" is, however, not to be taken to mean an unusually low place or break in the natural bank through which the water inundates an unimportant and small area. The common definition is the stage at which overflow of the natural banks of a stream begins to cause damage in the local area from inundation (flooding).

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NWS      USGS Station                                Flood 
Name     Number    Name                              Stage 
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NASW1    12010000   NASELLE R NR NASELLE              15.5 
WILW1    12013500   WILLAPA R NR WILLAPA              21.0 
DOTW1    12020000   CHEHALIS R NR DOTY               318.0
NEWW1    12025000   NEWAUKUM R NR CHEHALIS           202.5 
CENW1    12025500   CHEHALIS R NR CENTRALIA          168.5 
BCDW1    12026400   SKOOKUMCHUCK R NR BUCODA         211.5 
CTAW1    12026600   SKOOKUMCHUCK R AT CENTRALIA      189.0 
CGMW1    12027500   CHEHALIS R NR GRAND MOUND        141.0 
CRPW1    12031000   CHEHALIS R AT PORTER              48.0 
SATW1    12035000   SATSOP RIVER NEAR SATSOP          38.0 
MNSW1    12037400   WYNOOCHEE R NR MONTESANO          42.5 
BOGW1    12043015   BOGACHIEL R NR LA PUSH            37.0 
ELWW1    12045500   ELWHA R AT MCDONALD BR            20.0 
DRSW1    12048000   DUNGENESS R NR SEQUIM              7.0 
SRPW1    12061500   SKOKOMISH R NR POTLATCH           16.5 
DSRW1    12079000   DESCHUTES R NR RAINIER            11.0 
NISW1    12082500   NISQUALLY RIVER NR NATIONAL      8,000 cfs 
MKNW1    12089500   NISQUALLY R AT MCKENNA            10.0 
ORTW1    12093500   PUYALLUP RIVER NR ORTING        10,000 cfs
FFXW1    12094000   CARBON RIVER NR FAIRFAX           13.5 
SPEW1    12095000   S. PRAIRIE CREEK AT SOUTH PRAIRIE  
                     MINOR FLOOD FLOW WARNING LEVEL  4,000 cfs 
                     MODERATE FLOOD FLOW             5,500 cfs
                     MAJOR FLOOD FLOW                8,000 cfs
WRAW1    12100490   WHITE RIVER AT R ST NR AUBURN    7,500 cfs
PUYW1    12101500   PUYALLUP RI AT PUYALLUP           26.2
AUBW1    12113000   GREEN R NR AUBURN                9,000 cfs
LNDW1    12117500   CEDAR R NR LANDSBURG               5.7 
RNTW1    12119000   CEDAR R AT RENTON                 13.0 
ISSW1    12121600   ISSAQUAH CREEK NR MOUTH          2,000 cfs
SPEW1    12131500   SF SKYKOMISH RIVER AT SKYKOMISH
                     ACTION FLOOD WARNING LEVEL       26.0 ft 
                     MINOR FLOOD WARNING LEVEL        27.5 ft 
                     MODERATE FLOOD LEVEL             29.0 ft
                     MAJOR FLOOD LEVEL                30.0 ft
GLBW1    12134500   SKYKOMISH R NEAR GOLD BAR         15.0 
SQUW1    12144500   SNOQUALMIE R NR SNOQUALMIE      20,000 cfs 
TOLW1    12148500   TOLT R NR CARNATION              5,000 cfs 
CRNW1    12149000   SNOQUALMIE RIVER NR CARNATION     54.0 
MROW1    12150800   SNOHOMISH R AT MONROE             15.0
PILW1    12155300   PILCHUCK RIVER NEAR SNOHOMISH     18.0 
SNAW1    12155500   SNOHOMISH R AT SNOHOMISH          25.0 
GFLW1    12161000   SF STILLAGUAMISH GRANITE FALLS    14.0
ARGW1    12167000   NF STILLAGUAMISH NR ARLINGTON     13.0 
CONW1    12194000   SKAGIT RIVER NR CONCRETE          28.0 
MVEW1    12200500   SKAGIT R NR MT VERNON             28.0 
SMRW1    12201500   SAMISH RIVER NEAR BURLINGTON 
                     MINOR FLOOD FLOW WARNING LEVEL  3,000 cfs
                     MODERATE FLOOD FLOW             7,000 cfs
                     MAJOR FLOOD FLOW               11,000 cfs 
NSSW1    12210000   SF NOOKSACK R AT SAXON BRIDGE      8.0 
NRKW1    12210700   NOOKSACK R AT N CEDARVILLE       146.5
NREW1    12211200   NOOKSACK RIVER AT EVERSON, WA     83.5
NKSW1    12213100   NOOKSACK RIV AT FERNDALE          18.0 
FRYW1    12401500   KETTLE RIVER NEAR FERRY           18.5
SPOW1    12422500   SPOKANE RIVER AT SPOKANE          27.0 
HAGW1    12424000   HANGMAN CREEK AT SPOKANE          11.0 
LSDW1    12431000   LITTLE SPOKANE RIV AT DARTFORT     6.5 
NITW1    12442500   SIMILKAMEEN RIV NR NIGHTHAWK      14.0 
TONW1    12445000   OKANOGAN RIVER NR TONASKET        15.0 
PATW1    12449950   METHOW R NR PATEROS               10.0 
STHW1    12451000   STEHEKIN RIVER AT STEHEKIN        24.0
ARDW1    12452800   ENTIAT R NR ARDENVOIR              7.5 
PESW1    12459000   WENATCHEE R AT PESHASTIN          13.0 
PRDW1    12472800   COLUMBIA BL PRIEST RAPIDS DAM     32.0 
UMTW1    12484500   YAKIMA RIVER AT UMTANUM           35.5 
CLFW1    12490050   NACHES RIVER NR CLIFFDEL          31.0 
NACW1    12494000   NACHES RIVER NR NACHES            17.8 
PARW1    12505000   YAKIMA RIVER NR PARKER            10.0 
KIOW1    12510500   YAKIMA RIVER AT KIONA             13.0 
ANAW1    13334300   SNAKE RIVER NR ANATONE            20.0 
PULW1    13348000   SF PALOUSE RIVER AT PULLMAN        7.0 
TCHW1    14018500   WALLA WALLA RIV NR TOUCHET        13.0 
PITW1    14113000   KLICKITAT R NR PITT               9.00 
VANW1    14144700   COLUMBIA R AT VANCOUVER           16.0 
PACW1    14226500   COWLITZ R AT PACKWOOD             10.5 
RAWW1    14231000   COWLITZ R AT RANDLE               18.0 
MAYW1    14238000   COWLITZ R BLW MAYFIELD DAM      25,000 cfs
TOTW1    14242580   TOUTLE R AT TOWER BRIDGE         137.0 
CASW1    14243000   COWLITZ R AT CASTLE ROCK          48.0 
KELW1    14244200   COWLITZ R AT KELSO                21.5 
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