I have one of those thermal gun thermometers, where you can point it at something, and it tells you the temperatures. Honestly, we use it mostly to play with our cats because it has a little red dot laser pointer thing they like to chase.
Point being... if I point it at my pool it is pretty darn accurate reading the water temperature. And super easy, I can do it from my kitchen. They go for under $20 on Amazon.
I just bought one of those thermal gun thermometers off of Amazon. Thanks for the insight.