A View into Mesoscale Convective Systems from High-Frequency Soundings in the PECAN and RELAMPAGO Field Campaigns

Abstract:

Understanding of mesoscale convective systems (MCSs) has progressed as a result of observations from radars and satellites and high-resolution numerical model simulations. However, observations of the vertical structure of environments in which MCSs develop, and of characteristics such as their cold pools, continue to be limited. In two recent major field campaigns, targeted radiosonde observations from mobile platforms have been collected in and around MCSs to help address these gaps.

Plains Elevated Convection At Night (PECAN), in the central United States in 2015, and Remote sensing of Electrification, Lightning, And Mesoscale/microscale Processes with Adaptive Ground Observations (RELAMPAGO), in Argentina in 2018, both included observing MCSs as a primary objective. In both projects, high-frequency balloon-borne soundings were collected from a network of fixed and mobile radiosonde sites. Soundings in MCS inflow environments reveal rapid destabilization processes and moisture changes, as well as alterations to the vertical wind profile as convection initiates and approaches. These mesoscale processes are often inadequately represented in numerical weather prediction models. A large number of soundings within MCS outflow were also obtained during these campaigns; these types of observations have been very limited in previous studies. They show a diverse range of vertical structures, from deep, intense cold pools to situations where the strongest cooling is aloft. This presentation will review the insights that have been obtained from sounding observations in these field experiments, and highlight remaining questions that can be addressed in future research efforts.