Myths and legends surround how 4/20 became associated with marijuana

DENVER — There is something in the air today. Maybe you’ve noticed. April 20, or 4/20, is known as “Weed Day” in some circles because the date corresponds with a numerical code for marijuana.

Yes, it seems arbitrary. So how did the number 420 come to represent smoking pot?

Some claim the number is drawn from the California criminal codes used to punish the use or distribution of marijuana. But the state’s 420 code applies to obstructing entry on public land. So, not quite.

Neither the Los Angeles Police Department nor the New York Police Department even have a code 420. The San Francisco Police Department has one, but it’s for a juvenile disturbance.

Then there’s the legend of a Bob Dylan song.

In “Rainy Day Women #12 & 35” is a lyric, “Everybody must get stoned.”

Multiply 12 by 35 and you get 420. Seems a bit of a stretch and Dylan has never confirmed any link.

But according to Chris Conrad, curator of the Oaksterdam Cannabis Museum in Oakland, Calif., 420 started as a secret code among high schoolers in the early 1970s.

A group of friends at San Rafael High School in Marin County who called themselves “the Waldos” would often meet at 4:20 p.m. to get high.

For them, it was an ideal time. They were out of school but their parents still weren’t home, giving them a window of unsupervised freedom.

They met at that time every day near a statue of Louis Pasteur, the scientist who pioneered pasteurization.

The 4:20 time became a code for them to use in front of their unsuspecting parents and 420 gradually spread from there — possibly via Grateful Dead followers — across California and beyond.

It’s even the number of a California Senate bill that established the state’s medial marijuana program.

What was shorthand for a group of friends can now be seen on T-shirts, in Tinder bios (420 friendly) and throughout pop culture.

And of course, on the calendar every April.