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NEWAUKUM--NEAR CHEHALIS
   State:  Washington    County:  LEWIS
   Latitude:  46 37' 12" North    Longitude:  122 56' 43" West
   Elevation:  190 feet
   Supporting WFO:  Seattle    
   Action Stage:  200.5'   Flood Stage:  202.5'   Moderate Flood Stage:  204.5'
   Major Flood Stage:  205.5'

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.

NEWAUKUM--NEAR CHEHALIS   (NEWW1)
Forecasts for Water Year 2026
Ensemble Date: 2026-09-10
 Forecast Period: September 10 to January 1
Exceedence
Probability 		Stage
feet 		Discharge
CFS 		Probable
Date of Peak
95 % 196.51 1272 2026-11-08
90 % 196.91 1459 2026-11-16
70 % 199.72 3022 2026-11-25
50 % 201.45 4177 2026-12-06
30 % 202.90 5322 2026-12-16
10 % 205.00 8172 2026-12-25
05 % 205.47 9184 2026-12-28

Peakflow exceedence plot for NEWW1

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