Southwest Airlines has lowered its full-year guidance due to increased fuel expenses impacting its second-quarter profit. The carrier now anticipates full-year adjusted earnings per share to be between $3.25 and $4.25, a reduction from its previous forecast of at least $4. This updated outlook reflects a significant rise in fuel costs, which increased by $889 million in the latest quarter.

Previously, in April, Southwest had cautioned that its initial earnings projection was at risk because of escalating jet-fuel prices. The airline stated at the time that a decrease in fuel prices or a stronger revenue performance would be necessary to counteract the higher expenses and meet its target.

The company's latest profit guidance is predicated on the forward fuel curve as of July 17, assuming current fare levels and demand trends persist.