Gathering clouds

The storm clouds gathered over our condo.  However, we didn't actually get much rain. Although  later as we left for dinner we realised that there must have been a cloud burst just before we left our condo.  Why so specific?  I had looked out of the window just before we left, we were trying to decide if we needed to take umbrellas, it was dry then.  By the time we got down in the lift everywhere was wet, but the rain had stopped.