RTFV: A real time forecast verification system

To help forecasters realize maximum benefit from nowcast systems, we are developing a Real Time Forecast Verification system (RTFV) that uses the latest radar analyses and site-based observations to automatically and objectively verify nowcasts in near real time. It will be used during the Beijing 2008 Olympics WWRP Forecast Demonstration Project, which will demonstrate several state-of-the-art nowcast systems providing 0-6 h objective guidance on convective storm tracks, precipitation, and severe weather events. This is the first time that a real time verification system will be available during a forecast demonstration project or similar program.

RTFV verifies and inter-compares a variety of nowcast and forecast systems (including NWP and probabilistic forecasts) against a common reference dataset. It converts between point, cell, area, and grid spatial representations to allow a variety of data types to be used and comparisons to be made. RTFV displays maps, time series, scatter plots and a wide selection of standard verification scores, and offers several sophisticated diagnostic verification techniques including multi-scale and object-oriented approaches to further investigate the causes of forecast errors.

Graphical products are displayed within the verification application itself and also via linked web pages. In real time the visual and statistical displays are updated each time new observations become available, and results are sent to a verification database. RTFV can also be run manually to make use of non real time observations and to aggregate verification results.

RTFV is highly configurable so that all aspects of the input can be easily modified to suit new algorithms, observations, domains, etc. The design also allows new verification techniques to be easily added, providing a testing platform for advanced verification methods.