American Airlines stock jumped 2% in premarket trading Tuesday, after the carrier said its fourth-quarter revenue was set to be better than previously expected.

American (ticker: AAL) said it expects total revenue to be 17% down on 2019 levels in the fourth quarter, beating its previous forecast of 20% lower. The stock jumped more than 2% shortly after the improved guidance was released before slipping back to trade around 0.5% higher.

American's earlier guidance for revenue to be 20% lower than 2019 levels was made back in November, before the emergence of the Omicron coronavirus variant. Since then holiday travel demand has proved robust , at times topping prepandemic levels on traditional busy days.

The latter part of the holiday period and into the new year has proved more difficult with winter weather and Covid-induced staff shortages leading to widespread cancellations. American fared well in comparison with other airlines, canceling just 3% of flights between Dec. 26 and Jan. 9, according to data from flight tracking website FlightAware.com—for comparison, 8% of all U.S. domestic and international flights were canceled over that period.

American's improved revenue guidance is also ahead of Wall Street's expectations. Analysts expect the airline to post fourth-quarter revenue of $9.15 billion, according to FactSet data, a 19.2% drop versus the fourth quarter of 2019.

When it comes to capacity, the company said it flew 61.1 billion available seat miles in the final three months of 2021, 13% down against the same period in 2019, which was at the lower end of its previous guidance.

The airline's cost per available seat miles (excluding fuel)—used as a measure of efficiency—is set to be 13% to 14% higher than 2019 levels, higher than prior guidance of 8 to 10%. American put the increase down to lower capacity, its holiday operational incentive program, and a write-down of excess spare parts. The airline offered a $1,000 bonus to employees with perfect attendance over the holiday season in a bid to navigate the busy travel period .

Investors will be closely watching the airline sector's earnings in the coming weeks for indications of what impact the Omicron variant had in the final months of 2021 and for guidance on the rest of 2022. American may have given an early sign that the Omicron impact hasn't been as bad as first feared.

Earnings seasons will provide a more comprehensive answer in the weeks ahead. American will report fourth-quarter earnings on Jan. 20, while Delta Air Lines (DAL) will get things under way for the major U.S. airlines on Thursday.