MINNEAPOLIS (WCCO) — One of the most popular attractions at the Minnesota State Fair on Friday were the misters stationed periodically throughout the grounds.

You may think the water is what will cool you down, but it’s actually dropping the air temperature around it. And when you’re dealing with a hot day like Friday, those few degrees can make difference.

READ MORE: Mark Bell Charged With Fatally Shooting Girlfriend In St. Paul

Water and lots of it is one way we can stay cool. But our understanding of when to drink up may be misguided. Experts say you need to actually hydrate the day before the big event, instead of trying to play catchup.

Since few fairgoers know preparation takes place in advance, St. Paul Fire Captain Ken Adams says monitoring the output can help gauge the intake.

READ MORE: Minnesota Groups Unite To Oppose Recreational Marijuana Legalization

“If you’re going to bathroom once an hour or so, you’re well hydrated. If you’re not, then you should be drinking a little more,” he said.

In the corn roast booth, water isn’t the only way employees stay cool. Rising temperatures call for a change in worker routine, with breaks every hour out in the shade.

With thousands sweltering in the sun, medics were on alert at the fair Ready to help anyone recover and ultimately rejoin The Great Minnesota Get-Together.

MORE NEWS: St. Paul Police Searching For Shoplifter Who Shot Liquor Store Worker Over 6-Pack

The signs that heat exhaustion is setting in include light headedness and fatigue. If you experience those, get out of the heat and into some air conditioning (like at the WCCO-TV booth). The real sign of trouble is when you stop sweating.