The entrance quadrant of a jet streak is a thermally direct circulation.
— Jim Sullivan (@JimSullivan92) January 2, 2022
The warm side of that (right entrance) features ascent, which lifts and cools the air beneath that portion of the jet streak.
The jet streak over the Mid Atl really starts to rip after 0z tonight... 1/4 pic.twitter.com/Dx7jMc9jT2