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CHEHALIS--NEAR CENTRALIA
   State:  Washington    County:  LEWIS
   Latitude:  46 42' 42" North    Longitude:  122 58' 43" West
   Elevation:  185 feet
   Supporting WFO:  Seattle    
   Action Stage:  166'   Flood Stage:  168.5'   Moderate Flood Stage:  172'
   Major Flood Stage:  175.5'

Forecasts are calculated from a forecast time series that approximates flow at a 6 hour time step interval. Observed instantaneous peaks can be higher than model forecast peaks.

CHEHALIS--NEAR CENTRALIA   (CENW1)
Forecasts for Water Year 2026
Ensemble Date: 2025-12-06
 Forecast Period: December 6 to April 1
Exceedence
Probability 		Stage
feet 		Discharge
CFS 		Probable
Date of Peak
95 % 167.18 19747 2025-12-12
90 % 167.18 19747 2025-12-12
70 % 167.18 19747 2025-12-12
50 % 167.18 19747 2025-12-12
30 % 167.18 19747 2025-12-12
10 % 170.02 28935 2026-01-18
05 % 172.25 37946 2026-02-06

Peakflow exceedence plot for CENW1

 Click to download runoff traces used in forecast.  Click for comma delimited data used in plot.csv icon