IVP and EVS Case Studies

The OHRFC example verifies deterministic hydrologic forecasts using IVP. The MARFC example verifies probabilistic hydrologic forecasts using EVS.  Both IVP and EVS are NWS programs used for verification at hydrologic forecast points.

Scatter plot of observed versus forecast stage during OHRFC study for EVVI3 basin over long lead time intervals of 72-120 hours.
Box Plot of 30-hour Ensemble Forecast Errors Against Observed Value for Headwater Point at Williamsburg

Both case examples examine how the choice of whether or not to use Quantitative Precipitation Forecasts (QPF) as input for the hydrologic model impacts the hydrologic forecasts.