ABOUT DIGITAL NOAA RAINFALL DATA

The National Oceanographic and Atmospheric Administration (NOAA), which is the parent government organization of the National Weather Service (NWS), processes digital representations of rainfall. One of the tools NOAA uses compiles and analyzes Doppler radar-derived precipitation measurements, generating hourly grids with data points spaced at 1-km (1/2-mile) intervals across the continental United States – a so-called “rainfall map.”

This highly detailed picture of hourly data is based on a combination of various sources:

· Precipitation data from a network of 180 NWS-maintained overlapping dual-polarization Doppler radar networks.  

· Input from over 20,000 rain gauges.

· Satellite data processed every 15-minutes.

· Hourly automatic observations from reporting stations (often located at airports).

· Numerical models and climatology.

Among other uses, this digital rainfall map is input to NWS flood guidance, producing flash flood forecasts essential to public safety. In operation since 2014, this integrated weather data stream was awarded a NOAA Silver Medal in 2015, one of the highest recognitions conferred by NOAA. This data source is also used by the United States Geological Survey and the Army Corps of Engineers.

The key to this approach is the process of incorporating rain gauges into the hourly data stream alongside Doppler radar-derived rainfall measurements. Doppler radar computes precipitation based on the long-established empirical relationship between radar reflectivity measured from the beam and the rainfall rate. 

However, the beam is located above the ground, meaning it does not fully capture the amount of rain reaching the ground. Therefore, incorporating available rain gauges enhances the accuracy of the rainfall determined from the radar data.

WaterWatch PRO collects and processes this hourly digital rainfall map. Then, utilizing a proprietary method, WaterWatch PRO identifies a client’s GPS location within the nearest 1-km grid section. 

During processing, no further data interpolation is made of the client’s GPS location within the 1-km grid field. 

Our proprietary method delivers more precision to critical stormwater monitoring rainfall measurements. By using a computerized, automated system, WaterWatch PRO accounts for variances in time and space. 

This process makes WaterWatch PRO an ideal way to account for highly localized rainfall events, from a reliable NOAA data source you can confidently trust.