Harrold, Michelle, Jamie Wolff, John Halley Gotway, Paul
Oldenburg, and Zachary Trabold, National Center for Atmospheric Research/RAL
and DTC
The Weather Research and
Forecasting (WRF) model is a state-of-the-art numerical weather prediction
system used in both research and operational forecasting applications. The
model is highly configurable to the usersÕ requirements and suitable for a
broad spectrum of weather regimes.
Rigorously testing select configurations and evaluating the performance
for specific applications is necessary due to the flexibility offered by the
model. The Developmental Testbed Center (DTC) performed extensive testing and
evaluation with the Advanced Research WRF (ARW) dynamic core for two physics
suite configurations, with a goal of assessing the forecast and computational
performance of the updated Rapid Radiative Transfer Model (RRTMG) long- and
short-wave radiation schemes. One configuration was based on the Air Force
Weather AgencyÕs (AFWA) Operational Configuration, while the second
configuration substituted AFWAÕs current operational long- and short-wave
radiation schemes (RRTM/Dudhia) with the RRTMG radiation schemes. This
presentation will focus on assessing the forecast performance of these two
configurations; both configurations were run over the same set of cases,
allowing for a direct comparison of performance between the two. The evaluation
includes a forecast period from 2 June 2008 to 31 May 2009, with forecasts
being initialized every 36 hours; this extensive testing period allows for robust
results as well as the ability to investigate seasonal performance of the
configurations. Results will focus on the evaluation of traditional
verification metrics for surface and upper air variables, along with an
assessment of statistical and practical significance. A brief analysis of
computational resources required to run each configuration will also be
discussed.