This is what a poor quality roofing job gets you, shingles that literally blow off the roof. In this case it appears that the roofer may have put one nail in the shingles then stapled the rest of it. Yes, freaking staples!
I’ve blogged about it before, New Mexico gets very windy in the spring and fall. This spring we we had winds up to 50 MPH and the windy season seems, to me at least, have lasted longer than normal. The winds came from the west and this side of the roof faces west. Along with the poor attachment of the shingles leads the the perfect recipe for this problem. The previous owners must have had this problem because they had nailed many of the shingles on this side of the roof down. Yet they made the problem worse by nailing through the visible part of the shingle, which is bad because they essentially broke through the seal of the shingle, leaving a place for water to leak through. All those nail heads had to be covered with tar.
Repairing these missing shingles was pretty easy. I collected all the blown off shingles from around the property rather than buying new ones. I carefully slid the shingles under neath the tiles above it, where it was missing, and put it back in place where it matches the position of the other shingles. I then lifted the tile above it up enough so I could put some nails in, 4 nails per shingle. The nails are under the shingles where they belong and safe from the elements. Hopefully the tar on the shingles melts and holds the whole mess together, or at least thats how its suppose to work.