Peakflow Forecasts Header

COWLITZ--NEAR KOSMOS
   State:  Washington    County:  LEWIS
   Latitude:  46 27' 58" North    Longitude:  122 7' 5" West
   Elevation:  780 feet
   Supporting WFO:  Seattle    

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.

COWLITZ--NEAR KOSMOS   (COKW1)
Forecasts for Water Year
2025
Ensemble Date: 2025-07-08
Forecast Period: July 8 to November 1
Exceedence
Probability
Stage
feet
Discharge
CFS
Probable
Date of Peak
95 % 66.03 2167 2025-07-09
90 % 66.03 2167 2025-07-09
70 % 67.16 3394 2025-10-07
50 % 68.04 4646 2025-10-22
30 % 68.77 5888 2025-10-30
10 % 74.99 18316 2025-11-01
05 % 76.96 23989 2025-11-01

Peakflow exceedence plot for COKW1

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