Do I Need a Jacket Today?
You need a jacket when the feels-like temperature where you are is roughly below 60°F, and you need one sooner than that if it is windy, wet, overcast, or you will be outside longer than about twenty minutes. Feels-like matters more than the forecast number, because wind and humidity change how the same air temperature lands on skin. People differ: a threshold that suits one person can be five to ten degrees off for another.
The rough bands, and why they move
These are planning bands rather than thresholds. Read across the row for the conditions you will actually be in, not the conditions outside your window right now.
| Feels like | Still and sunny, short trip | Windy or overcast | Outside over an hour |
|---|---|---|---|
| 65°F and above | No jacket | No jacket | Consider a light layer after sunset |
| 55–65°F | Usually none | Light jacket | Light jacket |
| 45–55°F | Light jacket | Jacket | Jacket, closed shoes |
| 35–45°F | Jacket | Insulated jacket | Insulated jacket, hat |
| Below 35°F | Insulated coat | Coat, hat, gloves | Coat, hat, gloves, covered ears |
Two columns of the same row can disagree by a whole garment. That is the point: 55°F in still sun and 55°F in a 20 mph wind are not the same decision, and a forecast that reports only the air temperature cannot tell you which one you are walking into.
Why feels-like is the number that matters
Air temperature describes the air. Feels-like describes what the air does to a person standing in it, and that is what a jacket is for. Below roughly 50°F wind is the dominant correction, because moving air strips away the thin warm layer your body maintains against your skin. Above that, humidity dominates instead, because it governs how easily sweat can evaporate.
WhetherWear uses one feels-like value everywhere it appears, taken from the live observation for your location. The feels-like glossary entry explains how it is derived, and wind chill covers the cold half specifically.
When the general rule fails
- Direct sun is doing the work. Full sun on a still day can make 55°F feel like the mid-60s. Step into shade, or wait for the sun to drop, and the jacket is back.
- It is raining and you are in cotton. Near 50°F, a soaked cotton layer removes more warmth than a thin jacket adds. What you need is something that sheds water, not something that insulates.
- You are about to move. Walking briskly generates noticeable heat within about ten minutes. Dress for ten minutes in, not for the doorstep.
- You will be indoors most of the time. A jacket you carry all day is worse than a sweater you keep on.
- You are going out later than you think. The temperature you leave in is often not the one you come home in. See dressing for a temperature swing.
How WhetherWear works this out
WhetherWear reads the live feels-like temperature for your location, checks wind and precipitation, looks at how the temperature moves across the hours you will be out, and then adjusts for your activity and for whether you have told it you run warm or cold. The full method is published.
Related questions
Is 60 degrees jacket weather?
It is the borderline. At 60°F in still sun most people are comfortable without one; in wind, in shade, or after dark, most people want a light jacket. If you know you run cold, treat 60°F as a yes.
Do I need a jacket if it is sunny?
Sun raises how warm the same air feels, sometimes by several degrees, but only while you are in it. If your route is shaded, or you will still be out after sunset, decide on the shaded number rather than the sunny one.
Is a hoodie enough instead of a jacket?
A hoodie insulates but does not block wind or shed water. In still, dry conditions it substitutes for a light jacket down to roughly 50°F. In wind or rain it does not substitute at all.
Do I need a jacket just for the evening?
Often yes, even on a warm day. Clear skies let the ground lose heat quickly after sunset, so an evening can sit ten or more degrees below the afternoon peak.