Peakflow Forecasts Header

CHEHALIS--NEAR GRAND MOUND
   State:  Washington    County:  THURSTON
   Latitude:  46 46' 33" North    Longitude:  123 2' 9" West
   Elevation:  124 feet
   Supporting WFO:  Seattle    
   Action Stage:  138.5'   Flood Stage:  141'   Moderate Flood Stage:  142.5'
   Major Flood Stage:  144'

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--NEAR GRAND MOUND   (CGMW1)
Forecasts for Water Year 2024
Ensemble Date: 2024-04-25
 Forecast Period: April 25 to August 1
Exceedence
Probability 		Stage
feet 		Discharge
CFS 		Probable
Date of Peak
95 % 131.69 1839 2024-05-03
90 % 131.69 1839 2024-05-03
70 % 131.69 1839 2024-05-03
50 % 132.49 2726 2024-05-14
30 % 133.06 3476 2024-05-31
10 % 134.60 5637 2024-06-11
05 % 134.82 5970 2024-06-14

Peakflow exceedence plot for CGMW1

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