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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: 2026-09-15
 Forecast Period: September 15 to January 1
Exceedence
Probability 		Stage
feet 		Discharge
CFS 		Probable
Date of Peak
95 % 159.72 5293 2026-11-13
90 % 160.64 6446 2026-11-21
70 % 163.29 10657 2026-11-29
50 % 164.67 13475 2026-12-09
30 % 167.40 20352 2026-12-17
10 % 169.22 26079 2026-12-27
05 % 172.21 37738 2026-12-31

Peakflow exceedence plot for CENW1

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