What to Wear Running in 70°F Weather
70°F is 21°C. Everything below applies to either reading — the kit does not care which scale you think in.
Close to ideal. A single light layer works; you'll warm up quickly once you get moving.
What to Wear
Running kit for 70°F
- ●Short sleeve shirt
- ●shorts
- ●SPF if UV 3+
Women's variation
- ●Short sleeve shirt or tank
- ●shorts
- ●SPF if UV 3+
What 70°F actually feels like once you are moving
At 70°F running is heat-limited rather than cold-limited, and the number that decides the outing is not on most forecasts. A runner produces roughly three times a walker's metabolic heat and sheds it almost entirely by evaporating sweat — so humidity, not temperature, sets the ceiling. Above about 65°F of dewpoint the sweat stops evaporating efficiently and your pace at a given effort falls away regardless of fitness. At 6 mph you make only 6 mph of airflow to help, which is far less than a cyclist has at the same temperature.
Dress for the finish, not the doorstep
Your own engine is worth about 18°F once you are going. The practical rule is to dress for 88°F standing still rather than the 70°F on the forecast. Running gets the largest correction of the three because it makes the most heat, and runners still under-apply it. If you are comfortable on the doorstep at 70°F you are dressed for a walk, and you will be carrying a soaked layer by the second mile.
Not sure of the temperature? Enter your city in the free tool for live conditions, a Ride Score, and rain- and wind-adjusted advice.
Open the live toolThe first ten minutes
Start slower than feels right. At 70°F you reach working temperature within a few minutes and have nothing left to shed, so the only adjustment available to you after that is pace — and it is much easier to give up thirty seconds a mile at the start than four minutes at the end.
What changes at 70°F when it is wet, windy or bright
Rain
Rain at 70°F runs like roughly 60°F dry, but it troubles a runner less than it troubles anyone else here: you are making enough heat to stay ahead of it, and you are out for less time than a walker. A light shell helps; a heavy one will have you wetter from the inside than the rain would have made you.
Wind
A 15 mph headwind at 70°F adds meaningfully to the 6 mph you make yourself, and it lands hardest on an out-and-back — the half you run into it will feel colder and slower than the half with it behind. A thin windproof front is the right answer; run out into the wind and back with it where the route lets you choose.
Sun
Direct sun at 70°F can add the better part of 10°F to what you feel, and UV does not track temperature — clear, cool days burn people who never gave it a thought. Sunscreen on whatever the kit leaves out, and something over the eyes.
The mistake people make at 70°F
70°F is close to ideal for running and gets over-dressed anyway, because it sounds cooler than it runs. A runner at 70°F is making enough heat to be in a short sleeve within a mile; starting in a jacket means carrying it for the rest of the hour.
Hands, feet and ears
Nothing needs covering for warmth at 70°F. A cap and eye cover are worth having for sun and sweat; everything else is a hindrance.
Frequently asked
What should I wear running in 70°F?
For 70°F, wear: Short sleeve shirt, shorts, SPF if UV 3+. Dress for about 88°F rather than 70°F, because your own effort is worth roughly 18 degrees once you are moving.
Does 70°F feel colder when you are running?
Not in the way cold does. Above 50°F the airflow from moving at 6 mph mostly helps, by evaporating sweat — so 70°F feels cooler in motion than standing still. The risk at 70°F is overheating when you stop, not chilling while you move.
Should I dress differently running at 70°F than for cycling or walking?
Yes. A runner makes about three times a walker's heat, so you need noticeably less at 70°F than a walker does — but you make only 6 mph of airflow against a cyclist's 16, so you need less wind protection than a rider. Running is the least-clothed of the three at almost any temperature.
Is 70°F too cold to go running?
No — 70°F is comfortable for running with the right layers, and plenty of people consider it close to ideal once they are moving.
Do I need a jacket at 70°F?
Not for warmth. Carry a light wind shell in your waist or a vest pocket for the shade, the descent or the walk home, but leave it off at the start.
What should I wear running in 21°C?
21°C is 70°F, so the answer on this page is the one you want: Short sleeve shirt, shorts, SPF if UV 3+. Nothing about the advice changes with the scale — only the number you read off the forecast.
What changes if it rains at 70°F?
Treat it as roughly 60°F. Add a windproof or water-resistant shell over the same kit rather than adding insulation underneath — wet insulation holds water against the skin and is worse than none.