1. Real-time estimation of critical variables at various space-time scales;
2. Real-time quality control of observed precipitation and temperature data;
3. Short-term forecasts of precipitation based on radar and other data.

Because precipitation is the most important variable for hydrologic forecasting in many parts of the country, the primary focus of HG has been on Quantitative Precipitation Estimation (QPE), particularly using the nationwide network of Weather Surveillance Radars - 1988 Doppler (WSR-88D). Accordingly, many of the activities are in direct support of the so-called multiple stages of precipitation processing in the National Weather Service, which serve hydrologic forecasting operations at WFOs, RFCs and the National Center for Environmental Prediction (NCEP).

Ongoing activities include:

1. Improving the space-time resolution of precipitation estimates within the Advanced Weather Interactive Processing System (AWIPS);
2. Enhancing radar-based precipitation estimation and prediction techniques, and evaluating such techniques under development by other groups;
3. Developing statistical models for errors in precipitation estimates, a topic of importance to decision makers;
4. Refining and implementing algorithms for analysis of surface temperature in complex terrain.

New or refined techniques are introduced into operations by HL’s Hydrologic Software Engineering Branch, the Office of Science and Technology’s Systems Engineering Center, and the Office of Operational Systems Radar Operations Center (ROC).

We routinely consult with staff at field offices, the Office of Climate, Water, and Weather Services (OCCWS) and other researchers/developers, and to learn about user needs and new developments. Our major collaborators include the Radar Operations Center, the National Severe Storms Laboratory, the Atmospheric Physics Institute of the Czech Republic Academy of Sciences, and Universities.