Central PA Weird Cloud Loop From Friday

A strange cloud went over my house on Friday afternoon. It seemed to be a thunderstorm wanting to form but not quite making it. It didn't even contain any rain but did have mammatus clouds. You can see all the photos and webcam shots here. Below is one of the photos I took with my digital camera, looking southeast.

There were also strange cloud formations to the west of that one, and even further west. Although it wasn't a thunderstorm, it probably was a convective shower in the making, and the mammatus were a result of us being under the upper-level low pressure system, which often makes for heavy raindrops and small hail.

Here's an animation from my webcam (sorry, it's pretty quick and you have to press the Play button again to see it. If you want, you can download the quicktime movie in its original hi-res format | in the size shown below):