If you've ever headed out for a run on a muggy morning and felt like you were breathing through a wet sponge, you’ve experienced the effects of humidity and dew point firsthand. Runners talk about temperature all the time, but these two lesser-known weather factors can have just as much impact on performance and comfort.
What’s the Difference Between Humidity and Dew Point?
Most people are familiar with humidity percentage because it’s what weather apps display front and center. This number tells us how much moisture is in the air compared to the maximum amount it can hold at a given temperature. When humidity is high, sweat doesn’t evaporate as easily, making it harder for your body to cool itself.
But dew point is actually a better indicator of how the air will feel when you run. Dew point is the temperature at which air becomes fully saturated with moisture, meaning it can’t hold any more. The higher the dew point, the more oppressive the air feels.
How This Affects Your Running
Running in high humidity can feel like you're working harder than usual. When sweat lingers on your skin instead of evaporating, your body struggles to regulate temperature, and your heart rate climbs faster than it would in drier conditions.
But dew point is where things really start to make sense for runners. Here’s a general breakdown of how different dew points feel when running:
- Below 50°F: Dry and comfortable. You’re in the sweet spot.
- 50–60°F: Starting to feel some moisture, but still manageable.
- 60–65°F: Getting sticky. Your body has to work harder.
- 65–70°F: Uncomfortable. You’ll notice a drop in performance.
- 70°F and up: Oppressive. Your body’s cooling system is overwhelmed. Slow down and hydrate well.
What You Can Do About It
You can’t change the weather, but you can adjust your approach:
- Slow down: High humidity and dew points mean your body is working harder, so don’t expect to hit your usual paces. Effort-based training is your best friend.
- Hydrate properly: More moisture in the air doesn’t mean your body doesn’t need fluids. Electrolytes help keep your system balanced.
- Acclimate: Training in humid conditions gradually can help you adapt, but give yourself grace.
- Run early or late: Lower temps don’t always mean lower humidity, but avoiding direct sun can make a difference.
Work With Me
Understanding how weather affects your body is just one piece of the puzzle. If you're looking to optimize your training, adjust your pacing strategies, or figure out how to work with the conditions instead of fighting them, I can help. Let’s create a plan that keeps you running strong no matter what the forecast says. Reach out to learn more about working together.