The NWS' Real-Time Mesoscale Analysis and Analysis of Record

As part of the Digital Services program, NWS meteorologists produce high-resolution, gridded forecasts at field offices. The NDFD (National Digital Forecast Database) is derived from a mosaic of these gridded forecasts and is used by external NWS customers for various applications requiring weather forecast information. The NDFD has a nominal grid spacing of 5 km across the United States. Meteorological analyses play an important role in generating forecasts and forecast guidance. To date, gridded-forecast evaluations have been hindered by the lack of matching gridded analyses, and comprehensive verification of the forecast surface parameters. Many weather and climate applications also require, or would significantly benefit from, gridded analyses at fine scale (1-5km), for which other analyses (e.g., North American Mesoscale and Rapid Update Cycle (12-13 km)) are much too coarse. A single fine-scale, near real-time analysis covering the contiguous 48 states is non-existent. Thus, an immediate and critical need exists to produce a high spatial, high temporal, near real-time analysis to facilitate the creation of the NDFD forecasts and verify their accuracy. The second phase of work will create, in a more delayed mode, an Analysis of Record (AOR) of higher accuracy than the RTMA that will be suitable for verifying the NDFD. A third and final phase would be the retrospective application of the AOR for the purpose of deriving climatological and trend information at the same fine local scale. These analyses would incorporate data from the newer surface observing networks, including NERON (NOAA's Environmental Real-Time Observation Network) and mesonets collected by NOAA's Forecast System Laboratory's (FSL) MADIS (Meteorological Assimilation Data Ingest System). The AOR is sponsored by NOAA/NWS and U.S. Weather program. This project is intended to meet the needs for these analyses by providing a robust, scientifically rigorous, mesoscale analysis system useable in both near real time, and retrospectively to generate a past time series of analyses. The retrospective time series would be similar to the just completed regional re-analysis (done on a 32 km grid) except that it would be on a 5-km grid. AOR development will likely take place at EMC during the next several years, and will rely heavily upon collaborative efforts with scientists from NOAA laboratories and academic institutions. This paper will report on the development of FSL/EMC's (Environmental Modeling Center at NCEP) Real-Time Mesoscale Analysis (RTMA), the first phase of the prototype of the proposed AOR project, which has been underway over the past year.