Subjectively (or maybe culturally?), red tones are warm and blue tones are cool.
There's another definition of "colour temperature" (derived from a physical property, rated in Kelvin), in which blue-ish tones are warmer than red, white being the hottest. This is based on the light emission of very hot bodies (you can tell the temperature by the color it glows).
This second definition of "colour temperature" might be counter-intuitive but is used to rate light sources and in photography, so you have to know the context the term is used.
The hue attributed to black body radiation at a certain temperature represents the average color of the whole gamut of emitted frequency/intensities, which follows a curve with a peak that changes with the temperature (which is then perceived by the eye); this curve is a direct result of Planck's law.
At temperatures < 3000K, this is reddish
At temperatures between 3000-6000K, it becomes orange and then yellow
At temperatures around 6500K, it is white (this is close to sunlight, so the eye is tuned to this distribution and sees it as even)
At above 6500, it becomes increasingly blue.
Comments
About colour temperature:
Subjectively (or maybe culturally?), red tones are warm and blue tones are cool.
There's another definition of "colour temperature" (derived from a physical property, rated in Kelvin), in which blue-ish tones are warmer than red, white being the hottest. This is based on the light emission of very hot bodies (you can tell the temperature by the color it glows).
This second definition of "colour temperature" might be counter-intuitive but is used to rate light sources and in photography, so you have to know the context the term is used.
Blue is hotter than white by the kelvin scale.
The hue attributed to black body radiation at a certain temperature represents the average color of the whole gamut of emitted frequency/intensities, which follows a curve with a peak that changes with the temperature (which is then perceived by the eye); this curve is a direct result of Planck's law.
At temperatures < 3000K, this is reddish At temperatures between 3000-6000K, it becomes orange and then yellow At temperatures around 6500K, it is white (this is close to sunlight, so the eye is tuned to this distribution and sees it as even) At above 6500, it becomes increasingly blue.
That's right, thanks for the correction.