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CHEHALIS--AT PORTER
   State:  Washington    County:  GRAYS HARBOR
   Latitude:  46 56' 21" North    Longitude:  123 18' 50" West
   Elevation:  24 feet
   Supporting WFO:  Seattle    
   Action Stage:  45.5'   Flood Stage:  48'   Moderate Flood Stage:  50'
   Major Flood Stage:  52'

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.

CHEHALIS--AT PORTER   (CRPW1)
Forecasts for Water Year 2025
Ensemble Date: 2025-05-15
 Forecast Period: May 15 to September 1
Exceedence
Probability 		Stage
feet 		Discharge
CFS 		Probable
Date of Peak
95 % 32.30 1144 2025-05-19
90 % 32.30 1144 2025-05-19
70 % 32.30 1144 2025-05-19
50 % 32.53 1278 2025-05-31
30 % 33.30 1773 2025-06-12
10 % 34.55 2712 2025-06-20
05 % 35.89 3878 2025-06-29

Peakflow exceedence plot for CRPW1

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