Rabbits are built to tolerate really cold temperatures so a rabbit will usually be fine outside in cold weather as low as 32 For even lower provided the Rabbit has shelter from the wind and other elements and they're kept dry.
Although it's best to at least bring the rabbit into a garage with a heat lamp or some other form of heat to keep the garage or other place above freezing so the rabbit will be more comfortable.
At least make the rabbit a shelter where you can put a heat lamp to keep the rabbit as warm as possible.
The rabbit can tolerate some cold but I would not want to subject the rabbit to the cold when I can easily provide them some heat even in the form of a heat lamp.