Peakflow Forecasts Header

OKANOGAN--NEAR TONASKET
   State:  Washington    County:  OKANOGAN
   Latitude:  48 37' 57" North    Longitude:  119 27' 28" West
   Elevation:  861 feet
   Supporting WFO:  Spokane    
   Action Stage:  14'   Flood Stage:  15'   Moderate Flood Stage:  17'
   Major Flood Stage:  18'

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.

OKANOGAN--NEAR TONASKET   (TONW1)
Forecasts for Water Year 2025
Ensemble Date: 2025-05-12
 Forecast Period: May 12 to September 1
Exceedence
Probability 		Stage
feet 		Discharge
CFS 		Probable
Date of Peak
95 % 9.52 6854 2025-05-16
90 % 9.52 6854 2025-05-16
70 % 9.52 6854 2025-05-16
50 % 9.92 7590 2025-05-31
30 % 10.23 8170 2025-06-03
10 % 11.16 9904 2025-06-13
05 % 11.95 11455 2025-06-25

Peakflow exceedence plot for TONW1

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