What does WC 6 degrees celsius mean?

Answer 1

In this case WC stands for Wind Chill.

It is a subjective measure and tries to represent how much colder it feels on a windy day and the value depends on the actual still-air temperature and the speed of the wind where you are.

So, on a windy day if you stand, say, outside a barn it will feel colder than if you were standing inside the barn where the air temperature would be about the same but it would be almost still.

Calculation of wind chill is a bit complicated but as you can see it can vary by just where you are so is just an indication of how cold it's likely to feel.

6°C (Wind Chill) might represent an expected air temperature of 12°C with a fairly strong wind that will feel like it's just 6°C.

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