A popular Halloween and winter riddle is:
 
Q: What do you get when you cross a snowman with a vampire?
A: Frostbite.
 
The joke has been cited in print since at least 1989, and has been printed on many images.
 
       
Google Books
Smart Alec’s Revolting Jokes for Kids
New York, NY: Ballantine Books
1989, ©1987
Pg. 209:
What do you get if you cross a vampire with the Abominable Snowman?
Frostbite.
 
Google Books
Gross Out!
Over 150 Disgusting Jokes and Riddles
By R. M. Ferrara
New York, NY: Trumpet Club
1994
Pg. 48:
What do you get when you cross a vampire with a snowman?
Frostbite.
 
18 November 1994, The News Journal (Wilmington, DE)< "Just for Laughs," 55 Hours sec., pg. 16, col. 1:

Q. What do you get when you cross a snowman with a vampire?
A. Frostbite.
Nekaila White, 11
Wilmington
 
24 December 1995, Star Tribune (Minneapolis, MN), “FYI” by Maria Baca, pg. 1B:
What do you get when you cross a snowman with a vampire? Frostbite.
 
Google Groups: alt.humor.puns
[Fwd: Submit: Halloween Riddles]
Stan Kegel
10/30/00
(...)
What do you get when you cross a snowman with a vampire?
Frostbite.(By Richard Lederer and P. C. Swanson)
   
Google Books
The Megatastic Kids’ Joke Book
By Peter Coupe
London, UK: Arcturus
2001
Pg. 218:
What do you get if you cross the Abominable Snowman and Count Dracula?
Severe frostbite!
 
Google Books
Christmas Snowman Jokes For Kids
By Peter Crumpton
PeteyRF Creative
2015
Pg. ?:
What do you get when you cross a snowman and a vampire?
Frostbite.
 
Twitter
Kathleen Sender‏
@CoachSender
Since it’s so cold out…
What do you get when you cross a snowman and a vampire?
Frostbite
10:15 AM - 29 Oct 2017