C.C. I'm guessing the wind went from tailwind to headwind, not just a reduction in tailwind component? What??????????????????????????????????
I hope this is a joke from you. If not, please collect the Nobel price award, because you would be the first person on this planet, who would revoke existing physics laws.
As you know jet streams in the atmosphere is a phenomenon, caused by differences in air pressure in different parts of the planet earth, so basically the air flows from high pressure area in to low pressure area additionally accelerated through earth rotation. I have never ever seen the air flowing from low to high, for the same reason you can’t simultaneously use high and low pressure bleed valves for supply, because the high pressure air would flow in to low pressure compressor and definitely cause the engine stall. It’s either or.
So it’s definitely tail wind component reduction, but never two winds blowing against each other.
Cheers.