Dumb as a doorknob, dense as a block of wood...

[Megiddo]

Based on the cuurent weather, these are appropriate

Colder than a witches tit in a brass bra.

Colder than a well digger's ass in Alaska.

[BBAddict]

Cold enough to freeze the balls off a brass monkey--that one's interesting-it has an actual meaning from old warship days.

This piece of alleged history explains that in the olden days of sailing ships, cannon balls were stacked on the decks on brass plates called "monkeys." The plates had indentions in them that held the balls on the bottoms of the stacks. Brass, however, expands and contracts with the temperature and if it got cold enough, the cannon balls could fall...giving real foundation to the phrase "cold enough to freeze the balls off a brass monkey!"

[meat12]

colder than a witches titty

[phatchopper]

tighter than a nuns cunt

a few sandwiches short of a picnic

[Move2lt]

huh what the fu@#$! what are you guys talking about

[meat12]

a few cans short of a case:drunk:

[Henio]

About as sharp as a Marble,
Smart as a fence post,
Riding a south bound horse sitting north.