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Dear Weather People
I was outside having a cookout and I saw a jet smoke line to the left of me. Then I saw it again to the right above me. Next it was way to the right of me then farther to the right and then it was gone. I was wondering why it moved like that and still stayed in a straight line and if there was a science project to show how it happened like that. Could you please help me? Thank you
Cody
Tremonton Utah age 11
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Good question Cody, you are very observant, perhaps you have a future in weather!
Here's the scoop on contrails. Contrails form from the moisture in the exhaust coming out of a plane. This moisture cools and condenses and forms what a long looking cloud.
Sometimes you see the contrails dissapearing rapidly and other times, the streak sticks around. When we look at contrails we can look for information about upper air moisture and airflow (wind!).
If the contrail dissappears quickly, then we know the upper atmosphere is very dry, the moisture gets absorbed. If the contrail sticks around like it did for you, it floated around then went away, this would indicate that there is more moisture at higher altitudes. If your contrail stuck around for awhile, that would be a good sign that stormy weather or more moisture is on the way in the next day or so.
If the contrail moves quickly, we then know that the upper level winds are strong and inclement weather might be on the way. Actually, if you can look at the contrails without the aid of a fixed object to guage their movement, and really see them moving along quickly, the upper level winds might be 100 knots (around 115 mph) way up high!
Keep an eye on the sky as you already are, and you'll see all sorts of fun things!
Answered by KSL Meteorologist Dina Freedman.
