Detailed observations of complex dryline structure in Oklahoma on 14 April 1994

摘要: The dryline frequently observed in the Southern Plains is important as a favored zone for convective development in the spring and early summer (Rhea 1966), although the mechanism of convective initiation is not well known (Ziegler and Hane 1993). It represents the boundary separating warm, moist air, extending northward from the Gulf of Mexico, from drier air originating over the high terrain in the southwestern United States and Mexico. The basic characteristics of the dryline have been detailed by Schaefer (1986).Study of the dryline, as with any mesoscale meteorological phenomenon, has been hampered by the lack of high temporal and spatial resolution data. One solution has been to use observations from aircraft and mobile ballooning facilities to try to capture cross-sections across the dryline (Ziegler and Hane 1993). With the development and deployment of automated meteorological observing systems, it is now possible to observe the surface characteristics of the dryline with higher resolution than in the past. A network of such systems, the Oklahoma Mesonet (Crawford et al. 1994), has put at least one station in every county in Oklahoma recording standard meteorological variables every five minutes. In addition, over a small area of southwestern Oklahoma, a second network of identical sensors, the Agricultural Research Service (ARS), has placed 41 stations over an approximately 1000 km2 area, providing extremely dense observations in time and space. The two networks combine to provide" targets of opportunity" for case studies of meteorological events when they occur in the network any time of the year.