Tom Brady will sign a deal to officially bolt from New England to the Buccaneers ... and it's all going down on Wednesday -- this according to FS1 star Colin Cowherd.
"The Herd" host broke the news on his radio show Tuesday morning ... saying, "Tom Brady signs tomorrow with Tampa Bay."
"He has made a decision," Cowherd said ... "I am told Tampa is the choice and he will sign tomorrow."
Cowherd says his source is NOT a football one ... but rather someone close to Brady on business side.