A series of bullish oil headlines has sent crude soaring in recent sessions, but Tom Kloza of the Oil Price Information Service warns investors not to change their outlook too quickly.

"I would tell everybody to curb their enthusiasm for right now and really for the next 60 days," Kloza said Thursday on CNBC's "Futures Now." "We've heard it before ... I think this is a short covering rally."

Oil prices rose more than 4 percent Thursday after Saudi Energy Minister Khalid al-Falih said the country would take action to help stabilize global crude prices. Before that, the International Energy Agency predicted that oil markets will tighten in the coming months thanks to increasing demand. OPEC members are expected to meet in Algeria on Sept. 26-28, and some are hoping to see an agreement to freeze production in an effort to support prices.

Concerns about a global oversupply of crude have weighed on the oil markets and drove prices over the last few weeks — and, really, years. Yet Kloza said he disagrees with the IEA's assessment that the oil glut is being resolved.

"I was disturbed to see the International Energy Agency today basically come out and say the glut is gone, like the thrill is gone. It's not gone, it's not accruing like it was," he said. Kloza said best estimates indicate that demand is outpacing supply by about 300,000 to 400,000 barrels per day — far less than the million barrels forecast by the IEA, and not enough to remove the large global glut anytime soon.

Kloza added that traders who have sold whenever Saudi officials spread bullish rhetoric on oil have done quite well over the last two years. He said he thinks there may be a buying opportunity in the next 30 to 90 days, but this is not it.

"I think it gets a little bit worse before it gets much better," he said, adding that he doesn't see the hoped-for rebalance happening until maybe 2018.

Oil settled at $43.49 on Thursday, notching a 4.3 percent rise.