# Presentation: 385696

## The Areal Mean Basin Estimated Rainfall(AMBER) ProgramA Tool to Assist in Flash Flood Forecasting

- Ami Arthur
- Cooperative Institute for Mesoscale Meteorological Studies (CIMMS) /
- National Severe Storms Laboratory (NSSL),
- Western Intermountain Storms and Hydrometeorology (WISH) Team

## The AMBER Program

- Simply a large “book keeping” program to keep track of the precipitation falling in multiple basins.
- Input:  Precipitation estimates from the Weather Surveillance Radar - 1988 Doppler (WSR-88D)
- Output:  Average basin rainfall (ABR) rates and accumulations

## History of AMBER

- Developed by Bob Davis (Pittsburgh NWSFO) and Paul Jendrowski (Honolulu NWSFO) over the past 15 years.
- First operational in May 1985 at Pittsburgh.
- 10-mi2 basins delineated manually from a fishing stream map of Pennsylvania.
- Initially no ABR computation--simply overlay comparison with WSR-57 rainfall estimates.
- Eventually ABR computations were added, but all output was text-based.

## History of AMBER

- It was discovered that smaller basins were needed to be able to accurately forecast flash floods.
- 3-mi2 basins were manually delineated from 7.5-minute topographic maps.
- WSR-88D rainfall estimates were mapped to the basins.
- AMBER was operational with the 3-mi2 basins in May 1996 at Pittsburgh.
- AMBER was operational with 1-mi2 basins in urban areas in May 1999.

## History of AMBER

- In 1998, NSSL became involved in AMBER work.
- 10-mi2 basins were delineated in ArcView from  3-arc-second DEMs and RF1 data for the Tulsa, OK and Sterling, VA NWSFOs.
- A prototype graphical display was developed.
- AMBER and the new display were operational in Tulsa and Sterling by Fall 1998.
- In 1999, NSSL conducted a formal evaluation of AMBER at these two sites.

## AMBER Input

- The success of AMBER is highly dependent on three factors:
- Quality of the basin delineation
- Quality of the precipitation estimates
- The forecaster’s ability to interpret AMBER output and the hydrologic situation

## KINX (Tulsa) Radar Bin Centroids Mapped to the Delineated Basins

- KINX (Tulsa) Radar Bin Centroids Mapped to the Delineated Basins

## NSSL’s AMBER Display

## Future of AMBER

- The NWS plans to include an AMBER-like functionality as part of the Flash Flood Monitoring and Prediction (FFMP) program to be implemented in the Advanced Weather Interactive Processing System (AWIPS).
- An initial version will be operational by Summer 2001.
- Updates and modifications will continue after that.

## Future of AMBER

- NSSL has been tasked with delineating basins    (2-mi2 minimum basin threshold) and preparing FFMP data sets for every NWSFO in the country.
- This will be an initial effort to make the FFMP operational for everyone as quickly as possible.
- Use of the NED will assure the best quality possible for the initial basin cut.
- The basin delineation work done here can also benefit the NED-H project.
- An excellent opportunity for cooperation with EROS and minimization of duplicate efforts!

## Concluding Remarks

- AMBER provides valuable, up-to-date information to forecasters for many basins over various time intervals.
- AMBER monitors rainfall accumulation and rate on the basin level and alerts the forecaster to potential flash flooding.
- AMBER provides a much needed tool to assist in flash flood forecasting and warning decisions.