JetBlue Airways (JBLU - Get Report) took off Tuesday after a Citi analyst upgraded his rating on the airline to buy from neutral.

Kevin Crissey wrote in a note to investors that in the short term, he sees favorable pricing trends and lower fuel prices. He also believes earnings estimates will rise, spurred by a drop in fuel prices.

Crissey wrote that "with fuel prices now well below levels when guidance was provided, RASM, or revenue per available seat mile, can be weak or even negative, and JetBlue can still exceed consensus."

Wall Street is looking for roughly $2.30 in 2020 earnings per share, while the company has set a target of $2.50 to $3.

In April, JetBlue reported first-quarter earnings and revenue that glided past analysts' expectations amid an increase in passenger traffic and contained per-passenger costs.

Net income for the first quarter came in at $42 million, or 14 cents a share, compared with $90 million, or 28 cents a share, in the comparable year-earlier period. Analysts polled by FactSet had been expecting per-share earnings of 12 cents. On an adjusted basis, the company earned 16 cents a share.