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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: 2025-11-16
 Forecast Period: November 16 to March 1
Exceedence
Probability 		Stage
feet 		Discharge
CFS 		Probable
Date of Peak
95 % 197.59 1655 2025-11-29
90 % 198.80 2271 2025-12-04
70 % 202.16 4342 2025-12-29
50 % 203.45 5468 2026-01-09
30 % 204.21 6378 2026-01-29
10 % 206.00 11136 2026-02-20
05 % 206.00 14086 2026-02-23

Peakflow exceedence plot for NEWW1

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