Peakflow Forecasts Header

STILLAGUAMISH--NEAR ARLINGTON
   State:  Washington    County:  SNOHOMISH
   Latitude:  48 12' 13" North    Longitude:  122 7' 41" West
   Elevation:  65 feet
   Supporting WFO:  Seattle    
   Action Stage:  12.5'   Flood Stage:  14'   Moderate Flood Stage:  17.5'
   Major Flood Stage:  
19'

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.

STILLAGUAMISH--NEAR ARLINGTON   (ARLW1)
Forecasts for Water Year
2024
Ensemble Date: 2024-04-24
Forecast Period: April 24 to August 1
Exceedence
Probability
Stage
feet
Discharge
CFS
Probable
Date of Peak
95 % 4.53 7076 2024-04-29
90 % 4.53 7076 2024-04-29
70 % 5.02 8294 2024-05-08
50 % 5.66 9774 2024-05-20
30 % 6.09 11365 2024-05-30
10 % 7.63 15760 2024-07-07
05 % 8.80 19215 2024-07-15

Peakflow exceedence plot for ARLW1

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