A unique meteorological field experiment (COHMEX) is scheduled to be conducted from March-July 1986 with a core period of operation in June and July. It is taking place in the region covering northern Alabama and the adjoining portion of central Tennessee. The experiment's uniqueness derives from the fact that it is actually composed of three distinct experiments sponsored by National Aeronautics and Space Administration (NASA), the National Science Foundation (NSF), and the Federal Aviation Administration (FAA), respectively, with extensive sharing of resources and data. A diagram of the experiment's domain with observational coverage is included in Fig. 1.