My great uncle would say this, but instead of “than usual” he would say “strictly necessary”.
My dad would always say “Its so cold I have to bring the monkey inside” … because he wasn’t allowed to talk about monkey testicles (brass or otherwise) in front of children.
It is so cold the post man is peeing popsicles. (We once saw a postie peeing behind a bush)
Colder than a well digger’s chicken.
Courtesy of Ren (only watch the first 18 seconds):
Damn, plenty of uses of “polar bear’s” already.
Personally I prefer “a polar bear’s unmentionables”. Leaves plenty to the imagination.
“It’s colder than my ex-wife’s heart”
It’s so cold, I saw a fur wearing a fat lady."
One I used to hear:
It’s cold enough to freeze the balls off a pool table.
Colder than a three year old zombie.
Colder than divorce court in February.