Improving forecasts with storm-following nests

Details

• Journal Title:
  Bulletin of the American Meteorological Society
• Personal Author:
  Alaka, Ghassan J. ; Zhang, Xuejin ; Gopalakrishnan, Sundararaman G.
• NOAA Program & Office:
  OAR (Oceanic and Atmospheric Research) ; AOML (Atlantic Oceanographic and Meteorological Laboratory)
• Description:
  To forecast tropical cyclone (TC) intensity and structure changes with fidelity, numerical weather prediction models must be “high definition,” i.e., horizontal grid spacing ≤ 3 km, so that they permit clouds and convection and resolve sharp gradients of momentum and moisture in the eyewall and rainbands. Storm-following nests are computationally efficient at fine resolutions, providing a practical approach to improve TC intensity forecasts. Under the Hurricane Forecast Improvement Project, the operational Hurricane Weather Research and Forecasting (HWRF) system was developed to include telescopic, storm-following nests for a single TC per model integration. Subsequently, HWRF evolved into a state-of-the-art tool for TC predictions around the globe, although its single-storm nesting approach does not adequately simulate TC–TC interactions as they are observed. Basin-scale HWRF (HWRF-B) was developed later with a multistorm nesting approach to improve the simulation of TC–TC interactions by producing high-resolution forecasts for multiple TCs simultaneously. In this study, the multistorm nesting approach in HWRF-B was compared with a single-storm nesting approach using an otherwise identical model configuration. The multistorm approach demonstrated TC intensity forecast improvements, including more realistic TC–TC interactions. Storm-following nests developed in HWRF and HWRF-B will be foundational to NOAA’s next-generation hurricane application in the Unified Forecast System.
• Keywords:
  Forecasting Hurricanes
• Source:
  Bulletin of the American Meteorological Society, 103(3), E680-E703
• DOI:
  https://doi.org/10.1175/BAMS-D-20-0134.1
• Document Type:
  Journal Article
• Rights Information:
  Other
• Compliance:
  Submitted
• Main Document Checksum:
  urn:sha256:a19541cee754e4ff9e78b30692a196e3c2b422f1a4266c2029f86ae2b46a38ee
• Download URL:
  https://repository.library.noaa.gov/view/noaa/37584/noaa_37584_DS1.pdf
• File Type:
  [PDF - 5.88 MB ]