Assessing Deep Convection Initiation in a Mountain-Valley System Using Unoccupied Aircraft System Observations

Forecasts of the timing and location of deep convection are inadequate, as are scientists’ understanding of the dominant controlling mechanisms. The Lower Atmosphere Process Studies at Elevation, a Remotely-piloted Aircraft Team Experiment (LAPSE-RATE) field campaign, which took place in the San Luis Valley (SLV) of Colorado during July 2018, aimed to use in-situ observations to develop a deeper understanding of the processes relevant to deep convection initiation (DCI). The campaign resulted in a unique dataset, collected by a network of unoccupied aircraft systems (UAS) in a unique geographic setting, which can be used to examine the impact of terrain and land surface heterogeneity on DCI. During the first convection initiation-focused intensive operation period (IOP) of LAPSE-RATE, convection developed over the mountains first, produced an outflow boundary that moved into the SLV and subsequently played a role in DCI in the SLV. The objective of this research is to determine if mesoscale thermodynamic and kinematic ‘hot spots’ exist and if these correspond to the locations of DCI. This research highlights the value of dense networks of profiling UAS for sampling planetary boundary layer (PBL) features, including those relevant to the timing and location of DCI. Advisor: Adam L. Housto