After reviewing the forecast run results, you may need to adjust your model data to improve alignment between simulated and observed values—this process is known as model calibration.

The active forecast alternative in the Modeling tab shows which applications are used in the forecast. To edit data for a specific application, you can either:

  • Click the relevant application layer in the forecast tree and use the buttons in the Actions tab, or
  • Click the corresponding icon in the Modeling module toolbar to open the application’s native interface.

Any changes made within the Modeling tab apply only to the forecast alternative in the current forecast. Other forecast alternatives - and previous forecasts using the same alternative - will not reflect these updates. To ensure your changes applied in future forecasts, use the Save to Base option to copy the updates back to the base models. This feature is currently not available for HEC-MetVue or HEC-HMS model alternatives.

Example

To change the lookback storage (i.e., starting conditions) for a reservoir, you’ll edit the HEC-ResSim alternative included in the forecast. In the forecast tree, select the HEC-ResSim layer, then click Edit Alternatives in the Actions tab (located at the bottom of the Modeling tab). This opens the HEC-ResSim Alternative Editor, where you can update the starting storage and elevation values under the Lookback tab.