Mobile radar observations and damage assessment of the 24 May 2011, Canton Lake, OK tornado

The DOW7 and NOXP radars collected data on an EF3 tornado that occurred near Canton Lake, OK on 24 May 2011. Peak winds measured by the DOW7 radar were ~80 m s-1 at a height of 45 m above ground level and ~85 m s-1 by NOXP. An extensive ground-based damage survey was conducted immediately following the event, which resulted in the EF3 rating. An overview of the path of the tornado and the relationship between the damage and radar Doppler velocity will be presented.

The reflectivity presentation of the knob of the hook significantly evolves throughout the lifecycle of the tornado, most notably as a function of the type of debris present in the radar bins. In particular, while the tornado approached Canton Lake, a debris ball was detected. When the tornado moved over Canton Lake, the reflectivity structure of the knob exhibited a clear eye, but as the tornado moved northeast of the lake, over wooded land, a prominent debris ball replaced the clear eye. Dual-polarization signatures (Zdr and ρhv) also changed significantly as the tornado moved from land to lake surface and back to land.