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Is this a tell-tail sign of something I should be concerned about?

When I shut off the engine, exhaust continues to come out of the exhaust tip for about 90 seconds. What's odd is it seems to be coming out of the tip under slight pressure as opposed to just drifting out of the tip. Also, this evident mostly in the right rear exhaust.

I've owned the car for 10 years and I've never noticed this until now.

If it is just water vapor/smoke, after shutting off a hot engine, in a cold or damp environment, it's normal.

Could it just be condensation? It has been extra cold this winter. How long of a drive does it take for you to notice this?

Best to my knowledge, it's not condensation (I stuck my nose down there and took a whiff). With a warm engine, I can pull out of the driveway, drive it 100 yards and back into the driveway. Not sure it would do it if engine was dead cold.

Does it do it after you do a long trip? Could be something with the cat cooling off?

Ya know, I'm not sure. I'll make a note to check it after a long trip.

Just because you stick your nose in it doesn't mean condensation isn't present somewhere in the system. A byproduct of combustion is? Water! In this case, condensation. Therefore there is always water vapor somewhere in the process.

When hot air touches cold exhaust components, it creates condensation in spades. This is the heavy, thick, white/grey'ish smoke you see out the tailpipe when you pull out of your subdivision, after just starting it 2 minutes prior, and then you get on it. As the exhaust warms up to temp, it'll burn off the condensation and you'll see the thinner, whispier smoke out the tailpipe at that point. However, there still is water vapor in the exhaust stream itself, as again, the byproduct of combustion is? Water! So what it sounds like is that the exhaust has reached the point where it's burning off the condensation built up and you shut it off.

On a 90* day, this whole process takes place in but a few minutes. In the current cold, it can take 15 - 20 depending on how cold it is.

If you don't do much for drives that would warm the engine and exhaust up fully, that could definitely be part of it. Go for a 25 minute or so drive, make sure the engine is fully warmed up and you've driven for a bit with a fully heated up engine, then see what happens.

All kinds of stuff can build up in the exhaust, and when water freezes, it picks it up, then melts as the exhaust warms back up, that stuff can travel with it.

After a long drive, my car always continues to shoot steam out the poo chutes for a couple minutes depending on the temperature. Perfectly normal.