101.3°F. That's what the thermometer clipped to our fence read at 3:40 p.m. on August 14, in the shade. My son had a soccer game at 5, the lawn hadn't been cut in two weeks and the only air conditioning in reach was the car.
I spent that heatwave doing what I do for this site: testing. Five neck fans, two tabletop evaporative coolers, a cooling towel and a list of habits people swear by. Each one got the same treatment, an infrared thermometer on my skin before and after, air temperature and humidity logged every time. Some things cooled me down. Some only felt nice for a minute. One made things worse.
First, how your body actually cools off
Your body gets rid of heat mainly by sweating. The sweat only cools you when it evaporates, and it evaporates well when the air is dry and moving. That's why 95°F in Phoenix feels different from 95°F in Houston.
Keep that in mind, because it explains almost every number below. Anything that moves air across damp skin helps. Anything that adds humidity to air that is already wet helps a lot less. And once the air is hotter than your skin, which sits around 93 to 95°F on a hot day, a fan starts blowing heat at you instead of taking it away.
Neck fans: better than I expected, up to a point
Our five neck fans are still on the bench as I write this, now in their third week. The early numbers are consistent enough to share. At 88°F in the shade, ten minutes of a neck fan on medium dropped the skin temperature on the side of my neck by 3.8°F on average. My wife, who is much less patient with gadgets than I am, kept hers on through a whole afternoon of weeding.
At 101°F the story changed. The same fans dropped skin temperature by just 0.9°F, and after a while it felt like standing near a hair dryer on the cool setting. That lines up with public health advice: fans alone don't protect you once it's in the high 90s.
"It's great until noon. After that it's just moving the oven around." My neighbor Luis, who borrowed one for his roofing job
Two practical notes. Bladeless models didn't catch my daughter's hair, the bladed ones did twice. And battery claims were optimistic across the board: the model sold as "up to 12 hours" gave 7 hours 40 minutes on medium. The full scores go into our rankings once the 30 days are up.
So on hot but not brutal days, a neck fan earns its spot. On brutal days it needs a partner, and that partner turned out to cost about three dollars.
The combo that beat everything: water plus air
I soaked a plain cotton bandana in cold water, wrung it out and tied it loosely around my neck, then turned the neck fan on over it. At 101°F that combo dropped my neck skin temperature by 6.9°F in ten minutes. Nothing else we tried came close.
It works because you're giving the fan something to evaporate. The damp fabric does the job your sweat can't keep up with. Re-wet it every 20 to 25 minutes, when it starts to feel warm, and it keeps working.
Mini evaporative coolers: check the humidity first
These are the small boxes with a water tank and a wet pad that get sold as "personal air coolers." They are not air conditioners and they don't pretend to be, if you read the small print. They work like the bandana trick, just bigger.
Their results depended almost completely on the weather. Here's what we measured at 20 inches from the unit:
| Conditions | Air temperature drop | Worth it? |
|---|---|---|
| 96°F, 31% humidity | 6.1°F | Yes, clearly |
| 91°F, 52% humidity | 3.4°F | A little |
| 89°F, 71% humidity | 1.8°F | Not really |
In dry heat, on a patio table pointed at you, they're pleasant. In sticky heat they mostly add moisture to the air around you, and on the 71% day that made the porch feel muggier, not cooler. If your summers are humid, put the money toward a good neck fan and a cooler full of ice water instead.
Habits that cost nothing and measured well
Not everything needs a battery. These were the free moves that showed up in the log:
- Work before 10 a.m. On August 14 it was 81°F at 8:30 and 97°F by noon. I cut the lawn at 7:45 and it took the same 52 minutes, with half the misery.
- Stay off the concrete. Our driveway read 139°F at 2 p.m., the grass a few feet away 96°F. Put the chairs on the lawn and the kids' pool in the shade.
- Drink before you're thirsty. Roughly a cup of water every 15 to 20 minutes while you're working in heat is the usual guidance. I set a timer on my phone, because I always forget.
- Cold water on the wrists. Thirty seconds under a cold hose dropped my wrist skin temperature by 8.2°F, and it felt like more.
One warning I take seriously as a dad. Dizziness, headache, nausea or cold clammy skin mean heat exhaustion is starting. Stop, get somewhere cool and drink water. Confusion or hot dry skin means call 911. No gadget changes that.
My heatwave kit, after all the testing
By the end of August my backpack for the soccer field had settled into four things: a bladeless neck fan, two cotton bandanas, a small cooler with ice water and a spray bottle for the kids. Total cost under $60 if you already own the cooler. It got two kids through a Saturday tournament at 94°F without a single meltdown, and I include myself in that.
Nights are their own battle. Dana tracked what keeps you asleep when the bedroom won't cool down in her 45-night test on hot sleep. And if you want to know how we measure all this without fooling ourselves, it's written up on our how we test page.
Questions readers asked us
Do neck fans actually cool you down?
Yes, in moderate heat. We measured about a 3.8°F drop in neck skin temperature at 88°F. Above the mid 90s they help much less unless you pair them with damp fabric.
Do portable evaporative coolers work in humid weather?
Barely. In our test they cooled the air by 6.1°F in dry heat but only 1.8°F at 71% humidity. They're a good fit for dry climates and a poor one for muggy summers.
At what temperature does a fan stop helping?
Once the air gets close to your skin temperature, around the mid to high 90s, a fan mostly moves hot air. At that point you need water on the skin, shade or an air-conditioned place.
What's the fastest way to cool down outside?
Cold water on your wrists, neck and face, then moving air over the wet skin. In our test that beat every gadget on its own.