PI: Curtis James
Co-PI: Ronny Schroeder
CONVECT is a major meteorological field research project being proposed for July - August 2025 in north-central Arizona. The project is aimed at improving our understanding and ability to predict the convective development and organization of boundary layer thermals, thunderstorms, and mesoscale convective systems during the North American Monsoon (NAM).
The proposed field project is the Convective Organization aNd Venting Experiment in Complex Terrain (CONVECT), focused in north-central Arizona near the city of Prescott. This targeted region, encompassing the Black Hills, Verde and Prescott Valleys, and Mogollon Rim, provides an ideal laboratory for investigating processes connecting complex terrain to boundary-layer and convective processes. During the summer monsoon season, this region experiences frequent deep, precipitating convection. These storms typically initiate over the most prominent terrain features in this region and then may propagate into the populated lower lying areas or send out density currents or buoyancy bores that subsequently initiate new convection. The thunderstorms are generally spatially localized, forming over a deep convective boundary layer, but are often associated with pulse severe conditions (damaging wind gusts or large hail). Some cells may become terrain-locked or exhibit back-building behavior, leading to intense rainfall and flash flooding.
The multi-scale approach proposed for CONVECT will, for the first time, capture the complete physical chain of land-atmosphere processes that drive water vapor transport and monsoonal precipitation over complex terrain at meso- to micro-scales. This diurnally cycling chain includes energy and moisture exchange over a heterogeneous, sloping surface, thermally-driven planetary boundary layer (PBL) circulations, the venting of PBL air into the free troposphere, and the initiation, upscale growth, and propagation of deep convection. The proposed deployment includes a dense network of surface flux and energy balance probes, lower-tropospheric thermodynamic and kinematic profiling systems, mobile radars, and crewed and uncrewed aircraft with in-situ and remote sensors. The campaign will be carefully guided by multi-scale modeling, and in turn, experimental observations will be assimilated to evaluate their impact on multi-scale predictability and the validity of surface layer and PBL parameterizations in complex terrain. The CONVECT science team of instrument scientists and numerical modelers contains the necessary, complementary expertise in the surface layer, the boundary layer, and deep convection to substantially advance understanding of mountain exchange between the surface and free troposphere, as well as extreme precipitation, through a multi-scale lens.
Research Dates: 09/01/2024 to 08/31/2027