Peakflow Forecasts Header

BIG LOST--MACKAY RESERVOIR NEAR MACKAY
   State:  Idaho    County:  CUSTER
   Latitude:  43 57' 5" North    Longitude:  113 40' 27" West
   Elevation:  5946 feet
   Supporting WFO:  Pocatello    
   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.

BIG LOST--MACKAY RESERVOIR NEAR MACKAY   (MACI1)
Forecasts for Water Year
2025
Ensemble Date: 2025-05-12
Forecast Period: May 12 to September 1
Exceedence
Probability
Inflow
CFS
Probable
Date of Peak
95 % 590 2025-05-28
90 % 608 2025-05-29
70 % 822 2025-06-05
50 % 938 2025-06-08
30 % 1240 2025-06-12
10 % 1645 2025-06-21
05 % 2096 2025-06-25

Peakflow exceedence plot for MACI1

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