But I still dont know why the TAT is increasing while we are maintaining FL370 whilst in the jetstream.. if anyone can answer that Ill take my hat off to them!
If your in a jetstream the tat won't change much. If you did want to exit a jetstream, when tracking with it, a turn poleward will be the best course.
But your not in the jet stream... Your approaching it. From the north in this case as your tracking south it is flowing from your right to left.
So the tropopause is stepping down in front of you, and sloping down to the pole. As the worst turbulance is only patches up to 2000' deep either side of the core (yes the poleward lower section is worse) then changing altitude is the best course of action. So which way? When you approach a jetstream you watch the tat. If it is increasing - climb. If it is reducing - descend. Again due to the step up or down as you see it of the tropopause.
