Fiberglass bow in subzero temperatures?

Hi friends.

I have a 25# Kaya Windfighter as my first practice bow. I keep it in the house but shoot outside. It has been lately quite cold even here at the southern coast of Finland - usually winters are pretty lame at around zero Celsius, but now we happily have a real winter with lots of snow and occasionally below -20 Celsius.

Quite nice, but is this a hazard for a fiberglass bow? (No, I don´t stay out shooting the whole day ;-)

Arto