Wednesday, June 14
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TOPAZ data were recorded from 10:37 - 21:09 PDT. Warm temperatures (max. of 39 C), clear conditions, and light winds that followed the diurnal flow pattern. The mixed layer only reached about 1800 m agl. It entrained a thin ozone layer aloft containing moderate ozone concentrations (~75 ppbv) in the early afternoon and then slowly declined in depth through the afternoon. The warm temperatures, light winds, and the shallow boundary layer caused a buildup of ozone that reached 83 ppbv at the surface in the late afternooon. MDA8 ozone reached 74 ppbv at the TOPAZ lidar site.