Ligia Bernardet

Community Support and Transition of Research to Operations for the Hurricane Weather Research and Forecasting Model

AbstractThe Hurricane Weather Research and Forecasting Model (HWRF) is an operational model used to provide numerical guidance in support of tropical cyclone forecasting at the National Hurricane Center. HWRF is a complex multicomponent system, consisting of the Weather Research and Forecasting (WRF) atmospheric model coupled to the Princeton Ocean Model for Tropical Cyclones (POM-TC), a sophisticated initialization package including a data assimilation system and a set of postprocessing and vortex tracking tools. HWRF’s development is centralized at the Environmental Modeling Center of NOAA’s National Weather Service, but it incorporates contributions from a variety of scientists spread out over several governmental laboratories and academic institutions. This distributed development scenario poses significant challenges: a large number of scientists need to learn how to use the model, operational and research codes need to stay synchronized to avoid divergence, and promising new capabilities need to be ...

Sensitivity of hurricane forecasts to cumulus parameterizations in the HWRF model

The Developmental Testbed Center used the Hurricane Weather Research and Forecasting (HWRF) system to test the sensitivity of tropical cyclone track and intensity forecasts to different convective schemes. A control configuration that employed the HWRF Simplified Arakawa Scheme (SAS) was compared with the Kain-Fritsch and Tiedtke schemes, as well as with a newer implementation of the SAS. A comprehensive test for Atlantic and Eastern North Pacific storms shows that the SAS scheme produces the best track forecasts. Even though the convective parameterization was absent in the inner 3u2009km nest, the intensity forecasts are sensitive to the choice of cumulus scheme on the outer grids. The impact of convective-scale heating on the environmental flow accumulates in time since the hurricane vortex is cycled in the HWRF model initialization. This study shows that, for a given forecast, the sensitivity to cumulus parameterization combines the influence of physics and initial conditions.

Hurricane Weather Research and Forecasting (HWRF) Model: 2017 Scientific Documentation

1NOAA/NWS/NCEP Environmental Modeling Center, College Park, MD, 2NOAA Earth System Research Laboratory, CIRES / University of Colorado, and Developmental Testbed Center, Boulder, CO, 3National Center for Atmospheric Research and Developmental Testbed Center, Boulder, CO, 4University of Rhode Island, 5IMSG Inc, 6Geophysical Fluid Dynamics Laboratory, Princeton, NJ, 7Hurricane Research Division, AOML, Miami, FL,and RSMAS, CIMAS, University of Miami, Miami, FL