Arturo Estrella, the economist who first discovered the predictive power of the yield curve, has a message for recession naysayers: It could hit sooner than you think.

"It's been 50 years and 7 recessions with a perfect record," Estrella told CNBC in a message Thursday. "It's impossible to be 100% sure about the future but I'd say the chances of a recession in the second half next year are pretty high."

Estrella was a professor of economics at Rensselaer Polytechnic Institute and was once an economist at the New York Federal Reserve. Working at the Fed, Estrella studied the spread between the 10-year Treasury note and the 3-month Treasury bill as a recession predictor and found that particular part of the curve was the most accurate. It dipped below zero this year and is still inverted.