Hello so I have been getting better about reading the SigWx charts and understanding what I see however I am still confused about High and low Tropopause levels. Basically I understand what the tropopause is but I dont know how it plays into flight planning and what I need to differently if there is a high or low tropopause. For example if there is a low tropopause in a certain part of flight do I need to fly at a lower altitude so I stay in the jet stream or does it not really matter? Also how far does the warning usually cover from where it’s marked on the map
Hello: The best way to answer this is the following: CAT associated with a jet stream is most commonly found in the vicinity of the tropopause. CAT is most frequently found on the poleward side of the jet stream (over the United States, this is to the left side when facing downwind). CAT is also common in the vicinity of a jet stream maxima, a region of stronger winds within the jet stream that translates along the jet stream core. So you want go above the tropopause if able to provide smooth rides. However, if there are no PIREPS for turbulence jump in the jet stream if you have a tailwind try it out. Usually the weather will be calmer above this layer. Hope this helps.