JPMorgan downgrades United and JetBlue, says pace of comeback rally can't last for 'much longer'

A United Airline and a JetBlue airliner are seen in El Dorado International Airport in Bogota, Colombia.

Thierry Monasse | Corbis | Getty Images

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The run-up in red hot airline shares can’t last, according to JPMorgan.

The firm downgraded JetBlue to underweight from neutral and United Airlines to neutral from overweight on Tuesday,  citing four reasons why the rally is likely to end.

JPMorgan also lowered its revenue forecast for the major airlines for the second half. 

The rally in airline shares has been the talk of Wall Street lately. The U.S. Global Jets ETF, which contains all the major players, is up more than 80% from its pandemic low. The fund is up 50% in the last one month alone. United is up 75% in the last one month, while JetBlue is up 56%.

Investors have been betting on consumers slowly returning to the skies and airlines have been adding flights to their summer schedules.