Real-time WRF large-eddy simulations to support uncrewed aircraft system (UAS) flight planning and operations during 2018 LAPSE-RATE

Abstract

The simulation dataset described herein provides a high-resolution depiction of the four-dimensional variability of weather conditions across the northern half of the San Luis Valley, Colorado, during the 14–20 July 2018 Lower Atmospheric Profiling Studies at Elevation-A Remotely-Piloted Aircraft Team Experiment (LAPSE-RATE) field program. The simulations explicitly resolved phenomena (e.g., wind shift boundaries, vertical shear, strong thermals, turbulence in the boundary layer, fog, low ceilings and thunderstorms) that are potentially hazardous to small uncrewed aircraft system (UAS) operations. Details of the model configuration used to perform the simulations and the data-processing steps used to produce the final grids of state variables and other sensible weather products (e.g., ceiling and visibility, turbulence) are given. A nested (WRF) model configuration was used in which the innermost domain featured large-eddy-permitting 111 m grid spacing. The simulations, which were executed twice per day, were completed in under 6 h on the National Center for Atmospheric Research (NCAR) Cheyenne supercomputer using 59 cores (2124 processors). A few examples are provided to illustrate model skill at predicting fine-scale boundary layer structures and turbulence associated with drainage winds, up-valley flows and convective storm outflows. A subset of the data is available at the Zenodo data archive (https://zenodo.org/record/3706365#.X8VwZrd7mpo, Pinto et al., 2020b) while the full dataset is archived on the NCAR Digital Asset Services Hub (DASH) and may be obtained at https://doi.org/10.5065/83r2-0579 (Pinto et al., 2020a).