Peakflow Forecasts Header

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
2025
Ensemble Date: 2025-06-30
Forecast Period: June 30 to October 1
Exceedence
Probability
Stage
feet
Discharge
CFS
Probable
Date of Peak
95 % 2.44 20 2025-06-30
90 % 2.44 20 2025-06-30
70 % 2.62 32 2025-08-19
50 % 2.84 51 2025-09-08
30 % 3.03 72 2025-09-21
10 % 3.35 116 2025-09-30
05 % 3.90 229 2025-10-01

Peakflow exceedence plot for TCHW1

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