1. real-time quality control of the observed data,
2. real-time estimation of the variables at various space-time scales as required by various forecasting needs, and
3. real-time assimilation of the predicted values of the variables (e.g., Quantitative Precipitation Forecast, or, QPF) into the hydrologic prediction models.

Because precipitation is the more 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 performance of the WSR-88D Precipitation Processing Subsystem (PPS) (jointly with Princeton University and the University of Iowa in coordination with the WSR-88D Radar Operations Center (ROC))
2. Software engineering of the WSR-88D PPS (in coordination with ROC)
3. Enhancing/developing techniques and so