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WALLA WALLA--NEAR TOUCHET
   State:  Washington    County:  WALLA WALLA
   Latitude:  46 2' 0" North    Longitude:  118 44' 0" West
   Elevation:  405 feet
   Supporting WFO:  Pendleton    
   Action Stage:  10'   Flood Stage:  13'   Moderate Flood Stage:  15'
   Major Flood Stage:  17'

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.

WALLA WALLA--NEAR TOUCHET   (TCHW1)
Forecasts for Water Year 2026
Ensemble Date: 2026-05-14
 Forecast Period: May 14 to September 1
Exceedence
Probability 		Stage
feet 		Discharge
CFS 		Probable
Date of Peak
95 % 3.93 263 2026-05-14
90 % 3.93 263 2026-05-14
70 % 3.93 263 2026-05-14
50 % 4.07 299 2026-05-29
30 % 4.29 368 2026-06-05
10 % 4.78 544 2026-06-11
05 % 5.91 1128 2026-07-29

Peakflow exceedence plot for TCHW1

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