Tuesday, June 6
<br>
TOPAZ data were recorded from 9:49 - 20:21 PDT. 

Another hot day with a max of 103 F at the nearby NLVA (VGT) NWS station. Clear skies in the morning followed by widely dispersed contrail cirrus. The surface winds calmed during the night and ozone decreased to a locally tirated minimum between 5 and 10 ppbv between 0600 and 0700 PDT. The southwesterly winds gradually increased during the late morning with a mean speed of 12 m/s during the afternoon. TOPAZ showed the Pacific streamer to still be above Las Vegas between 3.5 and 4 km. The streamer was lifted up and disrupted by the mixed layer, which reached a height of about 3.5 km during the afternoon, but recovered most of its ozone density as the ML subsided in the early evening. A substantial amount of ozone was entrained into the ML, but not enough to raise the surface concentrations above 70 ppbv.