This was a first!  The first time I've ever seen a rainbow from an airplane!!!   I was enroute from Boston to Tampa and just before we attempted to land, I saw this......I had my camera in my lap, hoping for a shot of something from the air and this was my lucky day!  Especially lucky because when we were about 100 feet off the ground, the pilot hit the throttle and UP we went again!!!!  That was certainly a bit of a surprise!  There were lots of people doing the nervous laughter on the plane when the pilot came on to tell us there was a sudden downpour and THEY COULD NOT SEE THE RUNWAY!!!!!  Now.  I can tell you there was a downpour at that point, but the part about not being able to see the runway I cannot confirm as I was NOT DRIVING THE PLANE!!!!!  Fortunately, we did a nice loop around the airport and landed successfully on the second try.  I'm going to bed early.