Remember the disturbing scene from the film Day After Tomorrow, when a pair of oceanographers discovered that a second monitoring buoy was showing an alarming drop in water temperature. One could be an anomaly, or a malfunction. But the odds of two failures? Remote.

Before they could even begin to ponder the global ramifications, a third buoy indicator suddenly flashed red. There could be no mistake.

I’m reminded of that today.

Two weeks ago, Delta Air Lines (NYSE: DAL) cautioned that revenue growth was expected to stall out near zero (plus or minus a couple points) this quarter. Worse still, the company withdrew full-year guidance completely, citing a lack of visibility.

CEO Ed Bastian noted that near-term booking trends beyond the next two to three months were “a bit murky” adding it would “not be responsible to try to give an estimate in light of such uncertainty.”

Not a good look from the nation’s largest airline. Still, that didn’t necessarily mean that its peers were experiencing the same abrupt slowdown. Delta’s warning could be dismissed as a one-off situation.

Not anymore.

A second buoy beeped last week when Southwest Airlines (NYSE: LUV) opted not to reaffirm its 2025 guidance. The no-frills carrier had initially been projecting $1.7 billion in EBITDA this year, but is no longer willing to stand behind that figure.

Revenues per available seat mile (RASM) are now expected to be flat to down as much as 4% next quarter. CEO Bob Jordan characterized the sudden falloff in demand as a “consumer confidence erosion.”

Within hours, American Airlines (NYSE: AAL) yanked its 2025 outlook as well, acknowledging “the economic uncertainty that we’re going through… was certainly not anticipated a couple of months ago.”

That’s three flashing warning signs. Taken together, they send a clear indication of a cooling trend in the airline space. But if you need further validation, United Airlines (NYSE: UAL) echoed the others and said that the macro environment is ”impossible to predict this year with any degree of confidence.”

United decided not to withdraw its 2025 earnings forecast of up to $13.50 per share. For now. Instead, the company offered up a second scenario under which profits could fall to as low as $7.00 per share.

That’s about as wide of a guidance range as you’ll ever see – about like the weatherman saying tomorrow’s temperatures could be anywhere from 29 to 87 degrees. You can understand why Delta, Southwest and American were hesitant to even put forth a number.

To be clear, airports are still packed with travelers right now. The TSA has been screening about 2.5 million passengers per day, and throughput is currently on pace to match (or even beat) last year’s record volume of 904 million.

Delta claims to have a pretty good line of sight for the next 60 to 90 days. By late summer, however, we could be looking at a lot of empty seats – collateral damage from the trade wars. Tariff fears are likely to dampen big discretionary purchases – like flying the family to Orlando.

Consumer sentiment just nosedived 8% in April and has collapsed 32% from a year ago. Moods haven’t been this dour since the peak inflation scare of July 2022. What happened then? Well, not much – spending on concerts, sporting events, and vacations never wavered.

But in 2022, millions of households were still sitting on unspent stimulus checks and excess pandemic savings. That cushion is long gone.

As economists debate the likelihood that we could slide into recession, the airline sector may already be there. Southwest’s revenues dipped 3% in the first quarter and are expected to fall 6% in the current quarter – meeting the definition of two straight periods of contraction.

With a heavier emphasis on domestic leisure itineraries, Southwest is more exposed than rivals and could be the canary in the coal mine. That’s not to say that international flights are unaffected. The dollar has slumped to a multi-year low against a basket of foreign currencies, which could cause some fliers to rethink trips to London or Tokyo.

Corporate travel could also be on the downswing as companies postpone meetings and conferences. And if you query big hotel owners in destination markets like New York and San Francisco, there is already a noticeable drop in the number of international tourists arriving from Canada and Europe.

The Atlanta Fed has corroborated those findings, drawing on data from airports, stadiums and theme parks.

As you might expect, carriers have begun trimming back capacity in the second half of the year to better align supply with demand. United and Delta have both indicated plans to shave available seats by about 4% starting next quarter.

Needless to say, these headwinds have beaten down many stocks within this orbit. After reporting a healthy 13% bump in gross travel bookings last quarter (and paying a dividend for the first time since 2020), Expedia (NSDQ: EXPE) has swiftly dropped from $200 back to $160 per share.

On the positive side, demand can return as quickly as it left once trade uncertainties have been resolved. Until then, I would keep some distance from the legacy airlines.

But this cloudy outlook could benefit Air Lease (NYSE: AL), which operates one of the world’s largest aircraft leasing platforms. It owns a fleet of 500 rentals. We’re not talking about aging turboprops, but modern, fuel-efficient jets favored by global airlines, including the Boeing 787 Dreamliner.

With a spotless utilization rate of 100.0%, these planes are fully booked by 120 different carriers in 62 countries. American Airlines, AeroMexico and British Airways, just to name a few.

At a time of inflationary pressures and higher borrowing costs, leasing can be the smartest way for carriers to optimize their networks and maintain route flexibility amid volatile demand. And the cost savings can bolster the balance sheet, allowing these debt-laden companies to reach their deleveraging goals.

…which is why 50% of all new jets off the assembly line are rented rather than purchased. Since going public in 2011, Air Lease has returned $750 million in capital to stockholders.

Even in these turbulent times, that total will continue to climb.