2004 Annual Pawtuckaway Lake
Ice-Out Date Guessing Contest

What does "90% Ice Free" look like?

How do you decide when the lake is 90% ice-free?

Well, we could use a big tape measure and pocket calculator, but we're not feeling THAT ambitious. So we're gonna "use the force, luke" and make a judgement call here.

What does 90% look like? Well, work with me here.

A lake is kinda like a circle.

A lake covered with ice would look like this:

If you do the math (pi-r-squared, etc.), 90% ice free would look like this:

So that's what we're looking for! No problem.