NSSL scientists work to improve operational forecast models

The National Centers for Environmental Prediction's (NCEP) Environmental Modeling Center (EMC) is the primary source of numerical model forecast guidance for the National Weather Service (NWS). This central facility produces a relatively small number of guidance products for a diverse group of users. For example, forecasters specializing in aviation concerns, quantitative precipitation amounts, severe thunderstorms, tropical cyclones, winter weather and air quality all utilize the same model output. Because of this one-size-fits-all approach, the specific interests of individual groups often get compromised in the final product. At NSSL, the Mesoscale Applications Group (MAG) collaborates with Storm Prediction Center (SPC) forecasters, other NSSL scientists, EMC, and other modeling centers to explore various techniques to provide operational forecasters with more useful model guidance products for their specific needs.

This effort is led by Mike Baldwin and Jack Kain within the MAG group. Over the past several years, they have built on the foundation originally laid by Dave Stensrud at NSSL to develop unique configurations of both EMC's Eta model and the Penn State/NCAR mesoscale model (MM5). These configurations NSSL scientists work to improve operational forecast models.have been specifically designed to provide alternative algorithms for convective initiation and evolution, with more detailed mesoscale structure than the currently available operational models. Procedures have been developed to produce forecasts and transfer output from these models to N-AWIPS (National-center Advanced Weather Interactive Processing System) forecaster workstations in the SPC in a time frame comparable to EMC's operational procedures. Output is also posted on the Web and transferred to NCEP's Hydrometeorological Prediction Center. In addition, precipitation fields from these forecasts are verified against observations and EMC's operational models through an automated process that is updated daily and compiled on a monthly basis. EMC scientists are involved in this effort and have also begun to run an NSSL-like configuration of the Eta model in parallel to their real-time forecast.

SPC forecasters and research scientists have provided valuable feedback to support this work. In turn, the forecasters have developed a better understanding of the numerical models that provide their primary source of forecast guidance. Interrogation of model output is a frequent topic of conversation at daily NSSL/SPC map discussions. In addition, NSSL and SPC conducted an intensive program to evaluate operational and experimental models and algorithms during six week spring periods in 2000 and 2001 (see related article in the News Briefs). These programs have benefitted from participation by scientists from both EMC and National Oceanic and Atmospheric Administration's (NOAA) Forecast Systems Laboratory. Future plans for this group include real-time development and testing of the Weather Research and Forecasting (WRF) model, which is expected to replace the Eta model as the primary 1-2 day forecast model by the year 2005. Further information, including current model forecasts and verification statistics can be accessed from the NSSL home page at http://www.nssl.noaa.gov/modeling.shtml. By Jack Kain