[Ruatha]

It's the Gulf stream in the atlantic that warms us up.
Here were I live now we never have -40, some winters below -30 but that's rare.
Where my parents live it's sommetimes below -40 but that's very, very rare, but it's below -30 every winter.

EDIT: We use Celcius degrees, but -40 seems to be the same in both Fahrenheit and Celcius.