The 14th Conference on Hydrology

1A.13
INTERFACE FOR DISPLAYING PROBABILISTIC RIVER FORECASTS TO DECISION MAKERS

Louise F. Gunderson, Univ. of Virginia, Charlottesville, VA; and R. Krzysztofowicz

The probabilistic river stage forecast (PRSF) produced experimentally each day by the National Weather Service for a forecast point specifies probability distributions of the river stages at 7 AM on each of the subsequent three days. The river forecast interface (RFI) takes the parameters of these distributions and converts them into multiple graphical displays of (i) exceedance functions and decision rules (e.g., for flood watches and warnings), (ii) isoprobability time series, (iii) cross sections of the river channel, and (iv) inundation maps of the floodplain. Multiple graphical formats facilitate the communication of uncertainty about the river stage in time and in space. Provision for decision rules aids in the effective use of PRSFs. Imbedded probability thresholds, when exceeded, alert the forecaster to the need for issuing flood watches or warnings. Color-coded displays inform users about the status of flood watches and warnings. Because data from the PRSF system are passed as a text file, the RFI can be distributed to individual users. The software, written in Java and Hyper Text Markup Language (HTML), allows users with less sophisticated computers to own the RFI

The 14th Conference on Hydrology