Due to extreme volatility sensitivity (top pane), today was the the largest one day VIX % move since before Lehman, and likely ever (lower pane):
A termination level event and one that put a MASSIVE bid under the VIX futures (UVXY +40% after hours):
ZH: What Happens When VIX Goes Bananas
"A violent rise in volatility could be driven by just a 3% to 4% one-day S&P 500 selloff"
The 1-day percentage change is a big deal in the VIX complex because the levered and inverse VIX ETFs and ETNs rebalance daily based on the percentage change, and some of the thresholds for forced unwinds are based on the percentage change. This is why lower vol creates higher risk.
The Russell/Dow crash ratio duly warned this would happen: