The AROME-France Convective-Scale Operational Model

TLDR

The AROME‑France convective‑scale model became operational at Météo‑France in 2008 after six years of development and validation. The paper presents the main characteristics of the new AROME‑France NWP system, including its nonhydrostatic core, detailed moist physics, and 3D‑Var data assimilation. The system employs a nonhydrostatic dynamical core with detailed moist physics, 3D‑Var data assimilation, and incorporates specific dynamics options, variable settings, and physical parameterizations with their interactions. The 3D‑Var scheme’s scale‑specific features are demonstrated, and the model’s performance is evaluated with objective scores and case studies that reveal its benefits and weaknesses.

Abstract

Abstract After six years of scientific, technical developments and meteorological validation, the Application of Research to Operations at Mesoscale (AROME-France) convective-scale model became operational at Météo-France at the end of 2008. This paper presents the main characteristics of this new numerical weather prediction system: the nonhydrostatic dynamical model core, detailed moist physics, and the associated three-dimensional variational data assimilation (3D-Var) scheme. Dynamics options settings and variables are explained. The physical parameterizations are depicted as well as their mutual interactions. The scale-specific features of the 3D-Var scheme are shown. The performance of the forecast model is evaluated using objective scores and case studies that highlight its benefits and weaknesses.