Peakflow Forecasts Header

JOHNSON CREEK--AT SYCAMORE
   State:  Oregon    County:  MULTNOMAH
   Latitude:  45 28' 40" North    Longitude:  122 30' 24" West
   Elevation:  228 feet
   Supporting WFO:  Portland    
   Action Stage:  10'   Flood Stage:  11'   Moderate Flood Stage:  13'
   Major Flood Stage:  14'

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.

JOHNSON CREEK--AT SYCAMORE   (SYCO3)
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 % 1.61 14 2025-05-26
90 % 1.66 16 2025-05-28
70 % 1.79 21 2025-06-07
50 % 1.83 23 2025-06-11
30 % 2.12 37 2025-06-22
10 % 2.98 93 2025-07-19
05 % 3.92 174 2025-08-28

Peakflow exceedence plot for SYCO3

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