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NF STILLAGUAMISH--NEAR ARLINGTON
   State:  Washington    County:  SNOHOMISH
   Latitude:  48 15' 38" North    Longitude:  122 2' 51" West
   Elevation:  89 feet
   Supporting WFO:  Seattle    
   Action Stage:  10.7'   Flood Stage:  13'   Moderate Flood Stage:  14'
   Major Flood Stage:  15'

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.

NF STILLAGUAMISH--NEAR ARLINGTON   (ARGW1)
Forecasts for Water Year 2025
Ensemble Date: 2025-05-12
 Forecast Period: May 12 to September 1
Exceedence
Probability 		Stage
feet 		Discharge
CFS 		Probable
Date of Peak
95 % 3.20 1199 2025-05-21
90 % 3.20 1199 2025-05-21
70 % 3.76 1892 2025-05-28
50 % 4.19 2618 2025-06-10
30 % 4.55 3380 2025-06-17
10 % 5.60 5598 2025-07-16
05 % 6.44 7068 2025-08-02

Peakflow exceedence plot for ARGW1

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