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Real-time Modeling and Analysis
48-hr precipitation forecast incorporating soil conditions in the model run. (larger image)
Scientists at NSSL occasionally run numerical weather prediction models in real time in order to support field programs, experimental forecasting programs, and to produce large data sets when conducting model sensitivity tests. Real-time modeling is helpful because the model data are available daily for evaluation, from which one can gain a lot of information. Sometimes the real-time modeling consists of a standard run of a model in conjunction with a second run in which either a component of the model is modified or new observations are used to create the model initial conditions. These model forecasts are compared to determine if the modification or new data lead to improved forecasts. At other times, we may choose to run an ensemble (a group of model forecasts) to test ideas on how to create ensembles for short-range forecasting.
FORECASTS INCORPORATING SOIL CONDITIONS
Presently, NSSL is running an experiment to evaluate the potential value of mesonet data to model forecasts. One run uses initial data from the National Centers for Environmental Prediction, while the other incorporates Oklahoma Mesonet soil temperature and moisture data into the model initial conditions. It is believed that a better description of the soil conditions will lead to improved forecasts. Forecasts from this model evaluation are available at http://www.nssl.noaa.gov/neron
ENSEMBLE FORECASTING
An ensemble is simply a group of model forecasts that are valid over the identical time period. These forecasts provide information on the different ways in which the atmosphere may evolve over the next few hours or the next few days and even out to the next few weeks. Ensembles are needed because we do not have enough information to accurately depict the present state of the atmosphere. Even with all the information we obtain from satellites, radars, weather balloons, surface instruments, and other data sources we are unable to provide a perfect three-dimensional picture of the atmosphere at any given time. This means that the information we use to start a numerical weather forecast model, called an initial condition, is imperfect. These imperfections grow once the model starts and lead to forecasts that do not agree with the actual evolution of the atmosphere. More about ensemble forecasting »
STORM-TARGETED RADAR WIND RETRIEVAL SYSTEM
Researchers at NSSL and OU/CIMMS are developing a storm-targeted radar wind retrieval (STWR) system to provide forecasters with a desired comprehensive analysis tool to accurately analyze and monitor critical low-level wind conditions at very high resolutions. Forecasters will be able to access full horizontal vector wind information through a system that uses two relatively independent components: Warning Decision Support System-Integrated Information (WDSS II) and two-dimensional simple adjoint radar wind retrieval (2dSA). More about the Storm-Targeted Wind Retrieval System »
WEATHER RESEARCH and FORECAST MODEL (WRF)
The Weather Research and Forecasting (WRF) Model is a next-generation mesocale numerical weather prediction system designed to serve both operational forecasting and atmospheric research needs. The WRF model is currently being used operationally by the National Centers for Environmental Prediction. NSSL scientists have been major contributors to WRF development efforts and continue to provide leadership in the operational implementation and testing of WRF. More about WRF »
