Peakflow Forecasts Header

LONG TOM--FERN RIDGE DAM
   State:  Oregon    County:  LANE
   Latitude:  44 7' 24" North    Longitude:  123 17' 54" West
   Elevation:  374 feet
   Supporting WFO:  Portland    
   Inflow Data  

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.

LONG TOM--FERN RIDGE DAM   (FRNO3)
Forecasts for Water Year
2026
Ensemble Date: 2026-06-06
Forecast Period: June 6 to October 1
Exceedence
Probability
Inflow
CFS
Probable
Date of Peak
95 % 279 2026-06-09
90 % 279 2026-06-09
70 % 279 2026-06-09
50 % 279 2026-06-09
30 % 380 2026-08-30
10 % 584 2026-09-26
05 % 817 2026-09-29

Peakflow exceedence plot for FRNO3

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