The traffic lights, they turn blue tomorrow. Coca-Cola will begin magically running in all the school drinking fountains. People will begin emerging from the Department of Motor Vehicles thinking, “My, that was incredibly pleasant.” Or fire and brimstone will spew from cracks in the shattered earth as we plunge into the rapture and die.

Either way, nothing is unthinkable anymore now that something once considered scientifically impossible has occurred. There’s a Jewish-themed novelty rock group out there that’s — gasp! — actually really funny!

Rob Tannenbaum (the short one) and Sean Altman (the tall one) make up What I Like About Jew, a wickedly smart and funny duo spewing Semitic lyrics filthier than the walls of a Port-O-John that’s just been kicked down the side of Mt. Shasta.

Let’s make this crystal clear: If you’re offended by songs about engaging in a sexual act only recently ruled by the United States Supreme Court to be lawful in the state of Texas over the strenuous objections of Justice Antonin Scalia — in the synagogue lavatory during Sukkot — well, the Glenn Miller section is three back and two to the left.

But for the rest of you — and Justice Scalia is sure you’re all going to hell — the New York City duo will be playing selections from their debut album, “Unorthodox” at San Francisco’s Café du Nord on Tuesday, April 18 in a pair of shows sponsored by Heeb Magazine.

Eighteen (Chai) is a lucky number in Jewish circles, and, oftentimes, the 18 songs on “Unorthodox” aren’t just funny but “socially inappropriate public laughter” funny.

From a mixed-up rendition of the Passover story titled “They Tried To Kill Us (We Survived, Let’s Eat)”:

“Then the Pharaoh, who looked like Yul Brynner/Heard the Jews were trying to escape/Charlton Heston came right down from the mountain/ He said, ‘Pharaoh, you’re a damn dirty ape.'”

From an ode to the Web site JDate:

“Well you can ask a girl out if you like her look/It’s like Amazon.com, but with chicks instead of books/And if you have a bad time on your JDate/you can always go home and J-Masturbate.”

And from “Jews for Jesus,” a sadistic Johnny Lydon-esque screed against everyone’s favorite brainwashed pamphleteers:

“Like mayonnaise on rye/you make your bubbe cry/Go get your foreskin reattached/It’s time for you to die.”

Eighteen songs about Judaism is a lot to ask, and, of course, some of these songs aren’t Jewish. And some of them aren’t funny, either. And some of them seem filthy in a contrived manner, like a number about porno featuring a long list of the names of pantheon porno performers. Does knowing who Jenna Jameson is really make you taboo cool anymore? She has her own show on basic cable!

Tannenbaum and Altman’s stunning range can be a blessing as well as a curse. It’s remarkable, if you think about it, that one group can knock off Jewishly themed humor-pop numbers in styles reminiscent of the Sex Pistols, the Beatles, Big Bad Voodoo Daddy, Depeche Mode, a barbershop quartet and even Gilbert and Sullivan. But do we really need a song about circumcision set to a marching beat?

With the benefit of 20/20 hindsight, I should have seen What I Like About Jew coming. Jewish novelty albums pour into our offices here at j. with the rapidity (and, nearly universally, skill level) of Snoopy the dog’s attempts to pound out the Great American Novel.

I would rather go on a JDate with Justice Scalia than listen to most of these albums again. But, on one otherwise putrid ensemble was a catchy little number by What I Like About Jew called “(It’s Good to Be) A Jew at Christmas.” And it shined like the effort of a basketball player who knocks down 18 points and grabs 11 boards in a game his team lost by 35.

It should be simple — there are so many funny Jews and so many musically talented Jews, that you’d think the synergy would be natural. By God, it’s not.

So, What I Like About Jew’s solid album is even more remarkable. It’s like a test-taker scoring three standard deviations above the average (and these guys, when you think about it, are your average standard deviants).

The only downside is that their wit and success may encourage less-talented artists to crank out their own albums and send them to j.

What I Like About Jew will play 7:30 p.m. and 10 p.m. Tuesday, April 18 at Café du Nord, 2170 Market St., S.F. Tickets are $15; concertgoers must be 18. Information: (415) 861-5016 or www.cafedunord.com.