Peakflow Forecasts Header

SF BOISE--ANDERSON RANCH DAM
   State:  Idaho    County:  ELMORE
   Latitude:  43 21' 30" North    Longitude:  115 26' 44" West
   Elevation:  3880 feet
   Supporting WFO:  Boise    
   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.

SF BOISE--ANDERSON RANCH DAM   (ARAI1)
Forecasts for Water Year
2026
Ensemble Date: 2026-01-16
Forecast Period: January 16 to May 1
Exceedence
Probability
Inflow
CFS
Probable
Date of Peak
95 % 2522 2026-03-21
90 % 2607 2026-04-05
70 % 3036 2026-04-16
50 % 3356 2026-04-22
30 % 3896 2026-04-26
10 % 4854 2026-05-01
05 % 4889 2026-05-01

Peakflow exceedence plot for ARAI1

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