After many failed attempts I finally managed to capture a Circumhorizontal Arc. These are somewhat rare to see if you don't know what your looking for. I recommend you check out the wiki for more information, but in short...These occur when the sun is at a specific angle in the sky, and there are also cirrus clouds present.
They are sometimes called fire rainbows. If you can see a circumhorizontal arc where you live all depends on your location and the latitude. Here in the United States it is a relatively common to happen several times each year. Actually seeing them is somewhat tricky. I have read that they are quite rare to see mid-latitude and northern Europe.
Yesterday I helped my dad cut some trees down on his property. As we were cleaning up afterwords I looked up at the sky and noticed the clouds resembled the clouds I had seen when witnessing a circumhorizontal arc. I rushed inside and grabbed my camera, just as I was coming back out I saw it. I ran down to an empty field so I could get a better view. So after a few attempts of trying to get one of these captured in one of my photos... success!