"The Roaring Forties" represents the Times Square area (42nd Street). This appears to have been coined just after the first World War. "The Roaring Forties" is a 19th century term for the 40s years of a person's life; it also meant the 40th latitude.

Irving Lewis Allen's The City in Slang (1993), pages 60-61, notes: "The stretch of Broadway through Times Square was also called the Roaring Forties, or (in everyday use) just The Forties. ... Of these many named for Broadway, only The Great White Way has survived with vigor in popular speech."


30 December 1921, Iowa City Press-Citizen, pg. 4, col. 5:
NEW YORK - DAY-BY-DAY
Breezy Little Stories Told Daily of
THE GAY WHITE WAY AND BROADWAY LIFE
By O. O. McINTYRE
(...)
The Roaring Forties throbs with commotion.

12 February 1922, Syracuse (NY) Herald, pg. 3, col. 3:
COVERING NEW YORK
With the HERALD MAN
By ED ALLEN
(...)
The lesser Rialtos and Great White Ways, the Main streets, and the Four Corners and the Business Centers only reflect Times square and the once Roaring Forties.

25 September 1927, New York Times, pg. X18:
Nightly the "showman" takes his stand, and so alluring are his running advance descriptions of the trip through Chinatown that he has little difficulty drawing the attention of the stranger away from the bright lights of the Roaring Forties and in filling his car with expectant sightseers.

6 October 1937, Los Angeles Times, pg. 17:
Then for Times Square and the Roaring 'Forties.

The WPA Guide to New York City
New York: Random House
1939
New York: Pantheon Books
1982
Pg. 148: The theaters did not remain long in Herald Square and moved with the Tenderloin to the "Roaring Forties" of the Times Square area.

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