In the episode, New Neighbors, Lois yells at the lady for having the hedge trimmer wreck their hedges. When the sprinkler comes on, you see Lois from the back. You cannot tell how wet she is. When you see her from the front, she is absolutly drenched. This happened in about two seconds. In real life, she would have been splattered with water droplets and her hair would have been wet, but she looked like she had just jumped in a pool!

It just happened too fast for her to get that wet.