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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: 2025-07-05
 Forecast Period: July 5 to November 1
Exceedence
Probability 		Stage
feet 		Discharge
CFS 		Probable
Date of Peak
95 % 2.57 804 2025-08-27
90 % 3.36 1644 2025-09-28
70 % 4.58 3668 2025-10-15
50 % 6.13 6513 2025-10-23
30 % 7.86 9846 2025-10-27
10 % 10.13 14988 2025-10-31
05 % 10.76 16572 2025-11-01

Peakflow exceedence plot for ARGW1

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