Convection-allowing model

From Glossary of Meteorology

convection-allowing model

A numerical weather prediction model (i.e., numerical simulation) with sufficient spatial resolution to resolve the fundamental governing processes within deep convective storms explicitly rather than through parameterization. Convection-allowing models (also called convection-permitting models) typically have horizontal grid spacings ≤ 4 km, at which nonhydrostatic motions and system-scale circulations characteristic of organized deep convection are capable of being resolved. While horizontal grid spacings of order 1 km may be sufficient to represent the bulk properties and overall structure of convective storms (i.e., with horizontal spatial scales of order 10 km), smaller grid spacings (i.e., of order 100 m; see large-eddy simulation) are needed to explicitly resolve turbulent eddies within convective clouds and associated physical processes (e.g., entrainment).


Bryan, G. H., J. C. Wyngaard, and J. M. Fritsch, 2003: Resolution requirements for the simulation of deep moist convection. Mon. Wea. Rev., 131, 2394–2416, https://doi.org/10.1175/1520-0493(2003)131%3C2394:RRFTSO%3E2.0.CO;2.


——, and H. Morrison, 2012: Sensitivity of a simulated squall line to horizontal resolution and parameterization of microphysics. Mon. Wea. Rev., 140, 202–225, https://doi.org/10.1175/MWR-D-11-00046.1.


Schumacher, R. S., 2015: Resolution dependence of initiation and upscale growth of deep convection in convection-allowing forecasts of the 31 May–1 June 2013 supercell and MCS. Mon. Wea. Rev., 143, 4331–4354, https://doi.org/10.1175/MWR-D-15-0179.1.


Weisman, M. L., W. C. Skamarock, and J. B. Klemp, 1997: The resolution dependence of explicitly modeled convective systems. Mon. Wea. Rev., 125, 527–548, https://doi.org/10.1175/1520-0493(1997)125%3C0527:TRDOEM%3E2.0.CO;2.


Term edited 1 September 2023.


Copyright 2024 American Meteorological Society (AMS). For permission to reuse any portion of this work, please contact permissions@ametsoc.org. Any use of material in this work that is determined to be “fair use” under Section 107 of the U.S. Copyright Act (17 U.S. Code § 107) or that satisfies the conditions specified in Section 108 of the U.S.Copyright Act (17 USC § 108) does not require AMS’s permission. Republication, systematic reproduction, posting in electronic form, such as on a website or in a searchable database, or other uses of this material, except as exempted by the above statement, require written permission or a license from AMS. Additional details are provided in the AMS Copyright Policy statement.