On 20 June 2002, a remarkable bore was sampled in the course of an evening low level jet mission during which 2 aircraft (one equipped for launching dropsondes and one flying the water vapor differential absorption lidar LEANDRE 2) and a number of ground-based facilities (including the S-POL radar and other profiling instruments) located in the lower Oklahoma panhandle were deployed. The bore apparently was produced along a weak surface cold front enhanced locally by the outflow from a mesoscale convective system initially located in extreme western Kansas, along the Colorado border. As the outflow boundary propagated and expanded southward and eastward, it induced a bore and an accompanying wave train. The wave train propagated slowly southward from the northern Oklahoma Panhandle at 0400 UTC to the Oklahoma-Texas border, where S-POL and the other profiling instruments were operating (further referred to as Homestead), by 0600 UTC. The wave train began to break down after 0630 UTC, and really could not be discerned at all by 0730 UTC. During this night, the generation mechanisms for the bore have been documented by S-POL and the Dodge City WSR-88D radars. The evolution of the structure and dynamics of the bore into a soliton was well captured by LEANDRE 2 and S-POL measurements during the 0400-0600 UTC period. Finally, as the wave train broke down during its passage over the site, the Homestead observing systems were able to capture the dissolution of a soliton. Hence, this case offers the opportunity to examine the evolution of a gravity current into a bore, then a soliton, and its dissipation.
The life cycle of the bore as revealed from the synthesis of the observations is presently being compared with high-resolution three-dimensional and idealized models initialized with outputs from lower resolution models (20km RUC or 40km ETA) and IHOP_2002 observations.
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