Forecast Runs

A forecast run is a set of model alternatives that run sequentially during a forecast. As with model alternatives, forecast runs exist independent of time. Therefore, you can use a forecast run for any forecast time window. You create a forecast run by selecting a model alternative for each software application that could be part of a CWMS forecast. There are seven standard programs in CWMS, a typical forecast run will include a combination of the six model alternatives. When you execute a forecast, CWMS executes the software application in sequential order.

The table below provides suggested forecast runs. The codes are the names CWMS automatically assigns to each forecast run based on the one-character Model Alternative keys you have assigned to the model alternatives. This coding is program order dependent.

In the following example (Figure 1), the forecast run - Two times QPF has a key code of SWRBE. Each character in this key code is the key code that was assigned to each model alternative for each of the six standard software applications in CWMS.

Before creating a forecast run, you must have model alternatives. Model Alternatives and Forecast Runs provides details on how to create model alternatives. Creating forecast runs occurs in the Setup module which is detailed in Setup Module. Further details on managing forecast runs (e.g., opening, deleting) is provided in Model Alternatives and Forecast Runs.

Create a forecast run: 

1. From the CWMS CAVI main window, click the Setup tab, from the Models menu, click Forecast Runs. The Forecast Run Editor (Figure 2) will open.
   
   
2. Click New Run, the bottom section of the Forecast Run Editor is editable. The Models tab is populated with the software applications that are part of the selected Program Order (Default). Since a single model alternative key was defined for the ResSim, RAS, and FIA software applications, CWMS automatically displays the model alternative key and the model alternative name in the respective software application list.  The Key field displays the forecast run key which is built from what is selected from each software application list.
3. In the Name field (required), enter a name for the forecast run (Figure 2). You can enter a description in the Description box (optional).
4.  The program order being used is displayed in the Program Order list (Figure 2) and is not editable. See Program Order for more details..
5. From the software applications list (Figure 2), select the individual model alternates required for the forecast run. As you are selecting those model alternatives, in the Key box (Figure 2), CWMS is automatically creating the key for the forecast run, based on the individual model alternative keys (Setup Module).
6. You now have created a forecast run, from the Forecast Run Editor, from the Models tab, click Apply.  The table in the upper section of the Forecast Run Editor (Figure 2) displays the newly created forecast run.
7. Once the you have saved your forecast runs, from the Forecast Run Editor, click OK, the Forecast Run Editor will close. From the CWMS CAVI main window, from the Watershed tree, under the Forecast Runs folder, the names of the created forecast runs display.