Anxious for fun in the sun

I bought a slip and slide about 2 months ago. The kids having been asking me when they can use it. They would look outside and say "yep its sunny I guess mom will lets us play with the pool." I would then reply it is too cold. Well they got there wish today. I figured it was too cold but not so cold they would die. I set it up and they went down few times and then started to shiver. I think they know now that mom was right and it was still too cold for the "pool".