Radar estimated precipitation data is produced through a polarimetric technique developed at Weather Decision Technologies. Within radar echoes, hydrometeors are classified by the Polarimetric Radar Identification System (POLARIS), which is a technique largely based on the classification algorithm developed by the National Severe Storms Laboratory. POLARIS contains 3 non-hydrometeor (including tornadic debris) and 10 precipitation classifications with multiple hail size categories. A POLARIS Quantitative Precipitation Estimation (PQPE) system uses a suite of rain rate relationships dependent on reflectivity, differential reflectivity and/or specific differential phase. The hydrometeor type and location relative to freezing level determine which rain rate relationship is applied for each radar bin.
MetStorm is a new Geographic Information System (GIS) based analysis system that produces gridded precipitation at 5-minute and/or 1-hour intervals over a specified domain. The relative spatial precipitation patterns are largely governed by PQPE mosaics containing a spatial resolution of 1-km and updated every 2.5 minutes. Meanwhile, the precipitation magnitudes of MetStorm precipitation grids are influenced by quality-controlled rain gauge data from our strategic partner, Synoptic Data Corp. MetStorm has the ability to integrate both hourly- and daily-reported precipitation data, thereby providing a high degree of gauge density for ground truthing. Satellite data, though at a coarser spatial resolution (4-km), influences areas void of rain gauge and/or radar data. Innovative algorithms blend the precipitation estimates from the different sources into a seamless GIS grid, which provides the basis for summary statistics, maps, tables and plots.
MetStorm generates a unique set of storm precipitation analytics, including a depth-area-duration (DAD) table and plot, average recurrence interval map, and mass curve table/plot for the storms' center and a complete station catalog. A free subset of storm analytics are posted on the web for significant storms, while more in-depth analytics are available upon request. This presentation will include a synopsis of the PQPE system and brief overview of MetStorm with examples of recent storms.
Supplementary URL: metstat.com