Peakflow Forecasts Header

SANDY--SANDY
   State:  Oregon    County:  CLACKAMAS
   Latitude:  45 26' 57" North    Longitude:  122 14' 37" West
   Elevation:  240 feet
   Supporting WFO:  Portland    
   Action Stage:  18'   Flood Stage:  19.3'   Moderate Flood Stage:  20.5'
   Major Flood Stage:  21.5'

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.

SANDY--SANDY   (SNDO3)
Forecasts for Water Year 2026
Ensemble Date: 2026-02-18
 Forecast Period: February 18 to June 1
Exceedence
Probability 		Stage
feet 		Discharge
CFS 		Probable
Date of Peak
95 % 11.96 6707 2026-02-28
90 % 11.96 6708 2026-02-28
70 % 11.99 6798 2026-02-28
50 % 12.83 9411 2026-03-08
30 % 13.83 12399 2026-03-26
10 % 14.84 16140 2026-04-16
05 % 15.83 20364 2026-04-30

Peakflow exceedence plot for SNDO3

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