Jet Contrails From SE IA

[hendenhook]

Took this last week in Southeastern IA, I don't know alot about jet contrails, but I thought is was interesting that so many of these were crossong from different directions in the same part of the sky. They may need a traffic signal up there.

[mmeyer]

That's a great shot hh. The colors and the streaks are really cool.

[Dbl]

That just happens to be the crossroads for all the O'Hare traffic from the west coast and all the northbound traffic into Minneapolis. You were in the Ft. Dodge, Waterloo, Mason City area?

Cool shot as well, nicely done.

[Steve Foss]

I figured it must have been a Midwestern crossroads when I saw all those contrails. I know that, given the right atmospheric conditions, contrails will hang in the air a LONG time before dissipating.

Dan, how 'bout a little perspective on that? I swear I've seen contrails hold together for better than an hour sometimes after the jet is gone.

[Dbl]

Contrails are formed by condensation of water vapor in the exhaust of jet engines into ice crystals. If the atmosphere is dry at altitude you get no contrails, you must have a fair amount of water vapor in the atmosphere to get them.

Wator vapor present and wind at altitude determine how long they remain visible. Not much wind and fairly stable atmosphere and they can hang around for some time. Also a telling indicator of what the weather will be, contrails mean water vapor for telling possible unstable weather in the future.

Or something like that.

[Steve Foss]

We're getting that unstable weather right now. Supposed to last all weekend, too.

[Dbl]

 Originally Posted By: stfcatfish

We're getting that unstable weather right now. Supposed to last all weekend, too.

[hendenhook]

Dbl was down by the Quad Cities - could be St. Louis traffic too?

I do think it rained the next day and the wind switched from the south to the north so I could enjoy a headwind home too.

[Dbl]

From the Quad Cities probably still Chicago traffic on the east west contrails, north south could be Minneapolis, or anything south of that.

[Royce Aardahl]

Nice shot. Sure is busy up there.