The national average for gas was sitting just under $3 a gallon Monday morning. Enjoy it while it lasts.

What Happened

US and Israeli forces struck Iran over the weekend, triggering retaliatory attacks across the Middle East and sending oil markets into a tailspin. Brent crude jumped 8% to $79 per barrel, while US benchmark oil rose more than 7%. That kind of spike at the wholesale level moves to the pump fast.

"It's going to be very quickly," Patrick De Haan of GasBuddy told Yahoo Finance, predicting increases of 10 to 30 cents per gallon this week alone.

The Strait of Hormuz Problem

The bigger concern isn't just the attacks — it's the waterway they've disrupted. The Strait of Hormuz is a narrow passage between Iran and Oman that about 20% of the world's oil flows through every day. War-risk insurance premiums have spiked so sharply that shipping traffic through the strait has effectively stalled.

JPMorgan analysts warned that if the strait stays restricted for three to four weeks, Brent crude could push above $100 per barrel.

How Long Could This Last

Bad timing makes it worse. The US was already in the middle of its seasonal switch to cleaner, more expensive summer-blend gasoline — a transition that pushes prices up every spring regardless of what's happening overseas.

De Haan said drivers should expect higher prices "not just over the next few days but really the next several weeks, if not two or three months."

A gallon of gas was comfortably below $3 before this weekend. That era may be over for a while.