Peakflow Forecasts Header

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 2026
Ensemble Date: 2026-03-14
 Forecast Period: March 14 to July 1
Exceedence
Probability 		Stage
feet 		Discharge
CFS 		Probable
Date of Peak
95 % 48.60 26167 2026-03-15
90 % 48.60 26167 2026-03-15
70 % 48.60 26167 2026-03-15
50 % 48.60 26167 2026-03-15
30 % 48.60 26167 2026-03-15
10 % 48.60 26167 2026-03-15
05 % 48.69 26663 2026-03-31

Peakflow exceedence plot for CRPW1

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