Again, Thom and I were fortunate....had we not stopped in Miami OK to watch the funnel develop there, we probably would have been moving towards the developing hook northwest of Joplin 10 minutes earlier. That 10 minutes meant all the difference as the hook was enveloping Interstate 44 by the time we entered the western parts of the city. This the radar image we got just before we drove into that very broad hook and then stopped.
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Now we have leaned that the tornado was at least a half mile wide. Although the sirens were turned on 30 minutes before the tornado hit (and again 15 minutes before), there's not much one can do if the tornado was a high end event...besides leave the path. Apparently, just ahead of us on Interstate 44, 18 wheelers were lofted from the freeway, and homes were "slabbed" (according to reports from some colleagues who got to the town before the hook moved across the freeway). By the way, one of these chase colleagues is a doctor who today is serving as a volunteer for emergency services in Joplin. Also, one of my colleagues was there with a tour of individuals....they helped emergency services in search and rescue.
In any event, this is one of the reasons we prefer to chase in the western Great Plains. The population is sparse, and these sorts of sad things can't happen for supercells churning up the grassland. So the elation we feel at the success of our chase yesterday is tempered by the knowledge that the storms we are chasing can produce awful effects, like earthquakes, volcanic eruptions and tsunami.