Make Siri use Celsius instead of Fahrenheit for her weather report on the iPad

[UPDATE: Sept 2013] Since iOS7 came out this post became pretty much obsolete, because Siri will use your Region Format setting to determine which unit of measurement to use, pretty much means it'll just work. If you need a little reminder, its here: Settings > General > International > Region Format.

On iOS6, to have Siri report temperature in Celcius, the setup is in a strange place, its actually in the iPad clock app.

1. Launch the new Clock App on your iPad running iOS6.
2. Tap that Edit button on the top right.
3. On the pop-over you'll see Fahrenheit is selected, simply tap on Celsius.

Ask Siri again about the weather, she will now report the temperature in Celsius; excuse the Chinese words, those are simply city names.

iOS6