The Circuit Maneuver: A Strategy for Observing Tornadoes with two Mobile Mesonets

A primary goal of severe storm observations for a number of decades has been sampling the low level thermodynamic and kinematic flow in the near vicinity of low level circulations and tornadoes. This task however has represented a significant challenge in field operations to collect meaningful data that allows computation of divergence and circulation strength, and most importantly to do so safely. Limited observational platforms working on limited roadway options within the context of the larger severe weather environment present logistical challenges that prevent simply surrounding the circulation with observations. Furthermore, the ambient motion of such circulations and their potential strength represent a significant safety concern that must be the primary focus of any data collection strategy.

Toward this goal, NSSL has recently developed and employed the use of an observational technique referred to as a “Circuit Maneuver”. This observational strategy utilizes a road network perpendicular to the motion of the low level circulation to allow two mobile mesonet vehicles to adequately sample the near field environment while safely allowing the circulation to pass between the platforms. In this talk we will present the details of this maneuver, highlighting the safety procedures in place to minimize risk, as well as several examples of data collected during the recent PERiLS (2022-2023) and TORUS-Lite (2023) field projects utilizing this method.