US stock futures slipped as oil prices surged, a move that put traders on edge heading into the session. At the same time, the yen posted a sudden rally that caught out investors who had built positions on the currency's long-running weakness.
The two moves are connected. A jump in oil raises costs and inflation worries, which unsettles equity markets broadly. It also complicates the low-yield, weak-currency backdrop that has underpinned the yen carry trade — a strategy where investors borrow cheaply in yen to fund purchases of higher-yielding assets elsewhere. When the yen strengthens abruptly, those trades lose money fast and can force rapid unwinding.
What is not yet clear is whether this is a short-lived spike in oil and yen volatility or the start of a longer repricing. That will depend on how oil prices behave in the coming sessions and whether the yen's move proves durable or reverses.