It was President Trump’s very bad hair day.

A video shows the president climbing the stairs to Air Force One last Friday when a sudden gust of wind catches his combover.

The blast lifted the strands of hair like a flap and revealed his bare scalp underneath for all to see.

Trump’s hairdo has created volumes of speculation about whether it’s a wig, or implants, or his carefully coiffed natural hair.

In an interview with Rolling Stone magazine in May 2011, Trump walked a reporter through his cosmetic regimen.

“OK, what I do is, wash it with Head and Shoulders. I don’t dry it, though. I let it dry by itself. It takes about an hour,” he said.

Two recent medical examinations of the 71-year-old president also shed light on his mane.

His personal physician Dr. Harold Bornstei​n — who once proclaimed that if Trump were elected, “I can state unequivocally, ​[he] ​will be the healthiest individual ever elected to the presidency​” — assured that the president is fully tressed.

“He has all his hair,”​ Bornstein ​told reporters last year. “I have all my hair​.”

​He credited his full head of hair, as well as Trump’s, to taking finasteride, which is marketed as Propecia, a drug to treat male pattern baldness.

Last month, Dr. Ronny Jackson, the White House physician who examined Trump, said the president takes a range of medications, including Propecia.