The CBOE Volatility Index surged to 17.40 on July 13, 2026, as mounting geopolitical tensions in the Middle East sent shockwaves through U.S. stock markets and commodity prices. The spike in the volatility gauge reflected investor anxiety as the Nasdaq fell 1.5%, the S&P 500 declined 0.8%, and oil prices jumped sharply amid renewed US-Iran hostilities.
The market selloff was triggered by escalating military actions over the weekend in the Strait of Hormuz, one of the world’s most critical shipping routes for global oil supplies. According to reports from July 13, the U.S. and Iran exchanged fresh strikes, with both sides offering conflicting statements about whether the strategic waterway remained open to commerce. President Donald Trump’s announcement that he was reinstating a blockade of the Strait sent oil prices soaring.
Brent crude rallied 9.6% to $83.30 a barrel, while U.S. oil futures climbed 9.4%, according to the Wall Street Journal. The sharp move in energy markets hit technology and chip stocks particularly hard, as higher oil prices raise inflation concerns and increase operating costs for manufacturers. SK Hynix and other chipmakers led declines, with the Nasdaq composite losing more than 1.4% by late trading on July 13.
The VIX, which measures expected 30-day volatility implied by S&P 500 options, typically rises when investors expect sharp market swings or heightened uncertainty. At 17.40, the index remained well below the elevated levels seen earlier in 2026, when the initial Iran-US conflict in late February and March sent the VIX to intraday peaks above 35. However, the July 13 spike signaled a return to caution after weeks of relative calm in equity markets.
The Strait of Hormuz carries roughly one-fifth of global oil trade, making any disruption to shipping through the waterway a major concern for energy-dependent economies worldwide. Earlier in 2026, a prolonged closure of the strait had triggered the largest monthly increase in oil prices on record, according to retrieved reports. The renewed tensions on July 13 raised fresh fears that sustained blockade threats could disrupt energy supplies and further pressure already-elevated inflation readings.
Sources
- CNBC — VIX day high of 17.40 and opening price of 16.32 on July 13, 2026
- Wall Street Journal — Brent crude rallied 9.6% to $83.30, U.S. oil futures climbed 9.4% on July 13, 2026
- Barron’s — Nasdaq down 1.5%, S&P 500 fell 0.8% on July 13, 2026
- Reuters — S&P 500 down 0.68%, Nasdaq down 1.41% on July 13, 2026
- Bloomberg — US and Iran exchanged fresh strikes with conflicting statements on Strait of Hormuz status on July 12-13, 2026
- New York Times — Oil prices jumped after US-Iran back-and-forth strikes on July 12-13, 2026
- Charles Schwab — Mounting attacks over the weekend in Strait of Hormuz sent stocks, especially tech, down as oil rose
