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COLUMBIA--BLO PRIEST RAPIDS DAM
   State:  Washington    County:  GRANT
   Latitude:  46 37' 59" North    Longitude:  119 52' 0" West
   Elevation:  388 feet
   Supporting WFO:  Spokane    
   Action Stage:  31'   Flood Stage:  32'   Moderate Flood Stage:  33'
   Major Flood Stage:  34'

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.

COLUMBIA--BLO PRIEST RAPIDS DAM   (PRDW1)
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 % 13.09 94970 2026-11-01
90 % 13.14 95489 2026-11-03
70 % 13.34 97633 2026-11-08
50 % 14.06 105476 2026-12-02
30 % 15.12 117599 2026-12-20
10 % 17.57 147665 2026-12-29
05 % 18.45 158725 2026-12-31

Peakflow exceedence plot for PRDW1

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