That is what I was going to say, it looks like Altocumulus lenticular clouds to me. See them all the time, although not as stable as in your pictures.
....Bob (37 years in meteorology)
36 posted on 06/05/2009 5:39:05 PM PDT by Lokibob
(When handed lemons...Refuse to sign for them. Life's lemons can't be delivered without a signature.)