Sometimes there is a local law requiring that a car’s headlights be turned on when it’s raining. A joke about this was posted on Twitter  by Roy Beale on March 7, 2015:
   
“By law, you have to turn your headlights on when it’s raining in Sweden. How the hell will I know when it’s raining in Sweden??”
   
The March 2015 joke probably originated on Sickipedia, but there is at least one earlier version that did not involve Sweden. “By law you have to turn your headlights on when it’s raining in Florida. But who’s going to let me know when it’s raining in Florida?” was posted on Twitter on April 16, 2013.
 
         
Twitter 
Strange de Jim
@strangedejim
By law you have to turn your headlights on when it’s raining in Florida. But who’s going to let me know when it’s raining in Florida?
5:18 PM - 16 Apr 2013
       
Twitter
Fresh Stand Up
@FreshStandUp
I’ve just been reading that, by law, you have to turn your headlights on when it’s raining in ... http://bit.ly/1HcGAw2  via @sickipedia
11:11 AM - 7 Mar 2015
 
Twitter   
roy beale
@rbiom
By law, you have to turn your headlights on when it’s raining in Sweden.
How the hell will I know when it’s raining in Sweden??
12:17 PM - 7 Mar 2015
   
Twitter
😘Derek 🙈 🙉 🙊
@djspapa
@Ramblintweets Just read that, by law, you have to use your headlights if it’s raining in Sweden.
How will I know when it rains in Sweden?
6:00 PM - 7 Mar 2015
   
Twitter
Gary Anders
@GaryWorkid
BBCNews"by law, you have turn your headlights on when it’s raining in Sweden"great but how am I gonna find out when it’s raining in Sweden
9:26 PM - 7 Mar 2015
 
Facebook
Darren Broomhead
March 7, 2015 ·
iOS
I’ve just been reading that, by law, you have to turn your headlights on when it’s raining in Sweden.
And I’m thinking, “Who the fuck’s going to let me know when it’s raining in Sweden?”
   
Twitter
Sean M. Cullinan
@seanthemilkman7
It’s law to keep your car lights on when driving when it’s raining in Sweden…but how am I supposed to know when it’s raining in Sweden !
1:05 PM - 9 Apr 2016
 
Reddit—Jokes
By law, you are required to turn on your headlights if it’s raining in Sweden.
submitted April 11, 2016 by ChurchOfSkatan
How the hell am I supposed to know if it’s raining in Sweden?
   
22 June 2016, The Mercury (Durban, South Africa), pg. 6:
OVERHEARD in the Street Shelter for the Over-Forties: “I read that by law you have to switch on your headlights when it’s raining in Sweden. Now how the heck am I supposed to know when it’s raining in Sweden?”
 
Reddit—Jokes
TIL that, by law, you have to turn your headlights on when it’s raining in Sweden.
submitted March 9, 2017 by PaytheDevil
Who the fuck’s going to let me know when it’s raining in Sweden?
   
Reddit—Jokes
I’ve heard that, by law, you have to turn on your headlights when it is raining in Sweden….
submitted April 24, 2017 by thafezz
How the hell am I supposed to know if it’s raining in Sweden?
 
Reddit—Jokes
I’ve just been reading that, by law, you have to turn your headlights on when it’s raining in Sweden…
submitted July 13, 2017 by madazzahatter
And I’m thinking, “Who’s going to let me know when it’s raining in Sweden?”
 
Reddit—Jokes
By law, you are required to turn on your headlights if it is raining in Sweden.
submitted April 12, 2018 by Kyle______
How the hell am I supposed to know if its raining in Sweden?
 
Twitter
John
@JFD1960
I’ve just heard that it’s against the law to not put your headlights on when it’s raining in Sweden. How the fuck will I know if it’s raining in Sweden?
3:38 PM - 17 Apr 2018