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COWLITZ--AT PACKWOOD
   State:  Washington    County:  LEWIS
   Latitude:  46 37' 0" North    Longitude:  121 40' 59" West
   Elevation:  1048 feet
   Supporting WFO:  Seattle    
   Action Stage:  8.2'   Flood Stage:  10.5'   Moderate Flood Stage:  11'
   Major Flood Stage:  12'

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--AT PACKWOOD   (PACW1)
Forecasts for Water Year 2026
Ensemble Date: 2026-08-16
 Forecast Period: August 16 to December 1
Exceedence
Probability 		Stage
feet 		Discharge
CFS 		Probable
Date of Peak
95 % 1.77 885 2026-10-01
90 % 2.84 2009 2026-10-22
70 % 3.91 3633 2026-11-04
50 % 5.02 5854 2026-11-12
30 % 6.95 12028 2026-11-21
10 % 12.05 30591 2026-11-26
05 % 13.66 37640 2026-11-28

Peakflow exceedence plot for PACW1

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