A few years my wife and I saw a very fascinating meteorological phenomenon that I’ve been trying to figure out the factors that caused it. We ended up staying outside for a good half hour to an hour watching it pass. It’s been bugging me since. I wish I had my camera then to get a few pictures of it.

It was a heavily cloudy day, smooth cloud bottoms and fairly thick. Far on the horizon was a weird line in the clouds and it was headed our way. Basically, it looked sort of like an ocean wave filmed from underwater. It was like two layers of clouds. The existing layer was lifting up over the incoming layer which had a blunt, curved look to it. (And I’m positive the new layer was moving faster than the existing one.) For the first few hundred feet or so it was calm and then it transitioned into very turbulent conditions, large protrusions came down out of the cloud deck while large ‘holes’ were punched up into it and sections were swirling about. (I was also looking for a hidey-hole incase a tornado decided to drop out of it.) The winds were light to begin with and then strong and gusting as it arrived.

I’m sure it was a front coming through, but it was a rather spectacular arrival. If anybody has links to sites about this phenomenon I’d love to read up on it.

Right off the top of my head it sounds like this.

Sometimes little bitty gustnadoes form out in front of a strong cold front. The clouds can be very low hanging, dark and ominous. The initial wind can be very strong. One of my favorite things to watch is a gust front approach. I live in Oklahoma City and we get those.

I am not a meteorologist, so maybe meteora can help? I think I got that name right.

If it came from the northwest quadrant (assuming you´re in northern hemisphere), it must have been a cold front.

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Thanks, that's what I figured it was. The conditions were such that the it made for a real cool entry.

Your description does seem to match up fairly well with a cold front, although an old thunderstorm gust front is also a possibility. You did not mention if you heard any thunder, though that is not really necessary. It acts in the same fashion; rain-cooled air exiting the storm and heading out ahead of it. This can continue long after the storm has decayed. Then again, a storms' gust front is essentially a cold front, but on a significantly smaller scale.

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Nope, no thunder, that was the other thing that made it eerie, how quite everything was.

It would be helpful to know where this event took place - and what time of year. To me, it sounds more like the situation cyswxman describes - a gust front (a.k.a. "outflow boundary") from a thunderstorm complex. In the southern Plains, those things can make some wild cloud patterns, and they can travel several hundred miles from the thunderstorms that create them.

Do any of the photographs here look familiar? Apparently, Australia has some interesting storms, too...!

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"I am Meteora, supreme goddess of weather" - Meteora, in The Unchained Goddess

One nice thing about being a meteorologist who also likes astronomy is that the sky is always interesting!