Water Supply Forecast Maps

Streamflow Forecasts

Maps display the 50% exceedance forecast. For 90%, 70%, 30% and 10% exceedance forecasts, consult the State Water Supply Outlook Reports.

Westwide Map, 1st of Month, Percent of Median

Regional Maps, Percent of Median by Region:
Alaska | Arkansas, Colorado, Rio Grande Basins | Columbia Basin | Great Basin and California | Missouri Basin

Forecast Verification

April 1, 2022 50% Exceedance Forecast Error as Percent of NRCS Median

April 1, 2022 Observed Streamflow Exceedance Probability Category

More Information

Interpreting Water Supply Forecasts