I rode 138 somewhat hilly miles in high 80s/low 90s weather with dead calm in one direction, then about a 4 mph headwind on the return trip. I realized that at that temperature range, going uphill into the headwind was actually a little easier as the airflow was actually cooling me off a little. Anyone else think this?

Do you have any other seemingly paradoxical effects like this?

I cannot recall ever having a headwind being beneficial. Good that it was for you though.

If the headwind was the prevailing wind then I don’t know. But if it was katabatic (descendant air from higher ground) the air would be locally colder. More comfortable?

If going slow enough like in a climb, the headwinds doesn't feel as bad and they do help to cool off. Ofc, a strong tail wind would be a lot better to cool you off and also give a bit of push in a climb!

I guess another paradoxical effect in hot weather is riding up the mountains with at least 2000 ft altitude. The air is a bit thinner up there but the lower temperatures will help make the climb a lot more comfortable.

When going too fast, a decent headwind can be beneficial to me!

gm

It was definitely a matter of comfort. For me it was a sweet spot where the breeze was just strong enough to help evaporate sweat but not strong enough to make the climb seem harder. The thing I find worst about long hills on a hot day is the unevaporated sweat rolling down my face.

Two days ago, the temps were in the high 80s to low 90s (today it is 88) and I did get a tiny bit of relief when I was at the half-way point, I turned and got a headwind. It no doubt made me work a bit harder, but it did feel a bit better.

This was a weird natural experiment because there really wasn't any wind in the heading out direction, then I had the light wind in my face on the hilly part of the return. There was a series of relatively big rolling hills in the 10 miles or so leading to the turnaround, and I rode the same road in both directions.

I think that's exactly the temperature range I was dealing with.

it is so darn windy here that i can struggle descending. today was my second new route home from work, temps in the upper 90's, about 2000 ft of climbing, only 32+ miles, but nearly a 15mph head wind the whole way with 30+ gusts. wind has an intelligence here in reno, it knows where i am going and alters its course to "help" me.

Definitely. At 95F, I want a strong headwind both ways. A tailwind is the worst. OTOH, I probably wouldn’t want to ride 138 miles each way into a strong headwind at any temperature.

Otto

Oh yeah. Experienced the cooling effect of a headwind during my recent tour of Vermont. Several time I went off pavement in areas that were sheltered from the wind. I get very hot, and my last helmet purchase was a mistake.

Feeling no wind in a climb at 90F, hurts a lot. It's a lot more bearable at higher altitudes where it's colder. If only I could, I'd love to move to the mountains and live there for the rest of my life so I never have to deal with hot summers.

Definitely. In the winter and cooler part of shoulder seasons I'll ride out into the wind so it'll blow me home. On warm summer days it's the reverse -- ride out in the morning with the wind and hope you've got a headwind to cool you going home. Of course that assumes moderate winds; if it's calm in the morning and predictions are for 30 mph winds after 10:00, I'll still get cooling if I arrange my ride so it's a tailwind coming home in the afternoon.

The worst situation for me is a 5-10 mph tailwind when climbing at 5-10 mph. You think you get hot when there's NO breeze, try it when the wind actually cancels out any air movement!

If the wind speed over the ground is about the same as my speed over the ground. And my only choices are headwind or tailwind. I'll choose a headwind in any situation climbing or just cruising on level ground. I want air flowing around me.

Though destination and route will force me to deal with what ever I get.

With my bike, I don't need to draft, unless the headwind is pretty strong. In fact, I'd usually rather get the airflow. I am often found at the back of the group, to the upwind side, deliberately catching air. So yeah, I can believe it. That also goes for riding in dead air along with a tailwind, on a hot day. Dead air is bad -- like riding indoors!

i would rather never have a head wind, always no wind or a tail wind. i have never encountered a case where i was glad there was a head wind. in my experience rarely is the head wind direct toward me, it is always moving toward with a left right bias. same with the tail wind. so even if i am going as fast as a tail wind only occasionally is there a net zero effect. more often than not there is some lateral component to the wind either due to the wind or the road i am on.

absolutely - I don’t do well in the heat. Any breeze - even a headwind, within reason - is a benefit if I’m suffering

If the temp is too high (a few degrees below normal body temperature) then wind works like a convection oven and cooks you faster. It's the opposite of wind-chill.

TBH, until last Saturday, this would have been my position. It was just the right speed to not have a significant effect on my climbing speed, and I think it was just about 91 degrees. I've been riding for 50+ years and never felt that relief from a headwind before, which makes me think there's a really specific range of conditions where this might occur.

Also, people vary so much in how they sweat and in their body mass that these conditions might be different from person to person.

Upper 90s, definitely have felt that. Especially when it's humid.

A friend of mine says "Wind is your friend!"
(You better try to be its friend, as it will always be stronger than you)