“If you don’t like the weather, wait five minutes (and it will change)” is a weather saying in many parts of the world. Mark Twain (1835-1910) is often credited with originating it, but there is no record that he ever said it. The saying has been cited in print since at least 1915.
 
 
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The Yale Book of Quotations
Edited by Fred R. Shapiro
New Haven, CT: Yale University Press
2006
Pg. 782:
Mark Twain (Samuel Langhorne Clemons)
U.S. writer, 1835-1910
“If you don’t like the weather in New England, just wait a few minutes.”
Attributed in Bennett Cerf, Try and Stop Me (1944). An earlier version, not attributed to any individual, appeared in the Washington Post, 4 Mar. 1934, and referred to Washington, D.C.: “Just wait five minutes for a change—That’s what the weather here will do.”
   
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Reading the Weather
By Thomas Morris Longstreth
New York, NY: Outing Publishing Company
1915
Pg. 50:
With the optimism of that section of the country they say, “If you don’t like our weather, wait a minute.”
     
12 July 1925, Lincoln (NE) Sunday Star, pg. 4, col. 2:
If you don’t like Nebraska weather, wait fifteen minutes. 
 
3 March 1926, Portsmouth (OH) Daily Times, pg. 1, col. 2:
TAKE YOUR CHOICE
CLEVELAND, Ohio. March 3.—(UP).—A new “snappy comeback” is being offered by Clevelanders to visitors who have complained of erratic weather conditions in the vicinity during the past winter. It is:
 
“If you don’t like the Cleveland weather, wait a minute.”
       
24 December 1926, San Antonio (TX) Light, pg. 2A, col. 7:
Mercury in 18-hour
Stand at 35-Mark
CHICAGO, Dec. 24.—(AP)—The Chicago booster who said “If you don’t like Chicago’s weather, wait five minutes and it will change,” was all wrong.
 
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The Michigan Engineer
By Michigan Engineering Society
v. 46-48 - 1928  
Pg. 32:
But you know what Mark Twain said of the weather. “What! Don’t like Michigan weather? Wait ten minutes.” That’s what I say, “Wait ten minutes — it’ll be all over.”
 
20 March 1931, Olean (NY) Evening Herald, pg. 4, col. 1:
Mark Twain’s remark: “If you don’t like the weather, wait a minute,” is especially appropriate in March.
 
4 March 1934, Washington (DC) Post, “In Washington” by Katherine Smith, pg. SM2:
5. Typical.
The out-of-towners visiting
Are often prone to criticize
Our weather. Will it rain or snow,
Or sleet or shine?  We realize
Their indignation, and attempt
To pacify—we smile and coo,
“Just wait five minutes for a change—
That’s what the weather here will do.”
   
24 March 1937, Hartford (CT) Courant, pg. 7:
“If you don’t like New England weather, wait a minute.”
     
3 November 1937, Appleton (WI) Post-Crescent, pg. 30, col. 3:
...but it all gets back to Stoo’s original adage that has been repeated too, too often here—“if you don’t like Wisconsin weather, wait five minutes.”
   
28 May 1938, Chicago (IL) Daily Tribune, “A line o’ type or two,” pg. 8:
“If you don’t like Chicago weather, wait a minute…”
   
23 June 1939, New York (NY) Times, pg. 24:
For example, when he heard complaints against Nebraaka’s heat and cold, he commented: “If you don’t like Nebraska weather, wait a minute.”
     
22 August 1942, Chicago (IL) Tribune, “Midwest’s own direct Hawaiian island’s defense; Hole up with artillery on rain soaked mountain” by Robert Cromie, pg. 7:
The rain slops and starts so often their catch word is: “If you don’t like the weather wait a minute.”
   
26 September 1950, Chicago (IL) Daily Tribune, part 1, pg. 21 ad:
There is also that crack about if you don’t like the weather in Chicago just wait five minutes.
   
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1 April 1955, St. Petersburg (FL) Times, “Weather Wonders,” pg. 1, col. 7:
The old joke “If yon don’t like the weather, wait a minute!” has a new twist.
   
27 July 1969, Washington (DC) Post, “Provincetown Is Eroding, Like Cape Cod and the Haddock,” One of a series by the author of “The Strawberry Statement.“By James S. Kunen pg. 36:
Provincetown is trying not to think about it, girding itself instead for “the season.” “If you don’t like the weather, wait five minutes,” they say, referring to how the winds from the Atlantic bring in clouds only to sweep them away to rain on people who have not seen the sun.
   
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Keep Your Fingers in the Dirt
By Dorothy Bowen
Xulon Press
2009
Pg. 91:
Chapter Eight
Chapter Eight If You Don’t Like the Weather in Oklahoma, Wait Five Minutes
Will Rogers said. “If you don’t like the weather in Oklahoma, wait five minutes.” Okalhoma natives, in typical understatement, refer to the weather as “changeable.”