May 21st was a high potential set up in Iowa. A strong dry line, with fantastic shear, high CAPE and deep moisture would create a very dangerous environment in Iowa. By early afternoon storms exploded along the dry line and intensified as they moved east. Initial storms were not tornadic, but as the afternoon progressed, low level shear increased and tornadoes occurred with many storms! Our first tornado intercept was near Red Oak, Iowa as a supercell started spinning hard. The tornado went from a slender elephant trunk to a stovepipe and persisted for several minutes. The second tornado formed southwest of Carbon. It started as a big bowl, then vortices spun up and wrapping rain curtains were rotating violently around it. With motions of 60 mph we had to get out of its way as it approached us within a mile. The next tornado is now probably the most well-known. A strong multivortex tornado formed to our south near Corning and intensified as it moved northeast. It eventually turned into a raging F3 tornado that caused significant loss of property and life in the town of Greenfield. Our heartfelt sympathies go out to those who suffered losses there. Always the downside of significant tornadoes.  Another tornado occurred to our southeast as a cell raced north towards Creston but we lost it due to storm motion and another core with huge hail causing us to have to slow down. Crazy, wild day that most will never forget.