Color cast

I was taking photos at a football game yesterday. The afternoon was pretty bright, but there were some fluffy clouds passing by. I can't figure out why the first photo here is so bluish unless it is because I had my D300 WB set on SUN and a cloud came by. There were about a half dozen consecutive shots like this. All the others were 'normal.' These two photos were taken within a minute of each other.

Next question, since I shot in JPEG only, will it be simple to correct these in either PSE-10 or LR4? Even though I have LR4, I've never used it.