Alexander, Curtis, University of Colorado/ CIRES and NOAA/ESRL,
Steve Weygandt, NOAA/ESRL, Tanya Smirnova, University of Colorado/ CIRES and
NOAA/ESRL, Stan Benjamin, NOAA/ESRL, John Brown, NOAA/ESRL, David Dowell,
NOAA/ESRL, Patrick Hofmann, University of Colorado/ CIRES and NOAA/ESRL, Eric
James, University of Colorado/ CIRES and NOAA/ESRL, Ming Hu, University of
Colorado/ CIRES and NOAA/ESRL, Joe Olson, University of Colorado/ CIRES and
NOAA/ESRL, Kevin Brundage, CIRA and NOAA/ESRL, Susan Sahm, NOAA/ESRL, and Brian
Jamison, CIRA and NOAA/ESRL
The High Resolution
Rapid Refresh (HRRR) is a CONUS 3-km convection permitting atmospheric
prediction system run hourly in real-time at the NOAA Earth System Research
Laboratory. The HRRR uses the
WRF-ARW model and is run out to fifteen hours over a domain covering the entire
continental United States (CONUS), using initial and boundary conditions from
an hourly-cycled 13-km mesoscale model, the WRF-ARW-based Rapid Refresh (RAP).
A companion presentation will discuss the latest updates related to the current
and future RAP implementations.
In this presentation we will focus on changes to the HRRR model configuration including the adoption of WRF-ARWv3.3.1, vertical motion damping at the upper boundary, using fractional land-use categories with MODIS data, adjustments to the microphysics temperature tendency limit, and a coupling of the model reflectivity diagnostic with the latest Thompson microphysics scheme. A discussion of some ongoing challenges with our HRRR WRF configuration will be presented including problems with 6th-order diffusion and initialization of the near-surface wind field in complex terrain. Deficient cold-pool generation and associated challenges with mesoscale convective system maintenance will also be presented. We will conclude with a preview of potential HRRR changes for 2013 including model physics and data assimilation at the 3-km scale.