The National Weather Service in Chanhassen offered a recap on the mild autumn in the Twin Cities, along with some late season snow statistics.

 

PUBLIC INFORMATION STATEMENT...UPDATED FOR FINAL NUMBERS
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
825 AM CST WED DEC 1 2004

...SIXTH WARMEST AUTUMN IN TWIN CITIES HISTORY...
TWIN CITIES RESIDENTS WENT FROM WONDERING WHEN THINGS WOULD WARM UP
 (AFTER THE 14TH COOLEST METEOROLOGICAL SUMMER (JUN-AUG) IN MINNEAPOLIS HISTORY)...
TO WHEN THINGS ARE GOING TO COOL DOWN. THE METEOROLOGICAL AUTUMN IN THE TWIN CITIES...
AS MEASURED BY THE TEMPERATURES TAKEN AT THE MINNEAPOLIS INTERNATIONAL AIRPORT...
WAS QUITE THE REVERSAL FROM THE COOL...DRY SUMMER. THE AUTUMN RANKED TIED FOR 6TH WARMEST 
IN HISTORY...USING RECORDS DATING BACK TO 1891. THE METEOROLOGICAL AUTUMN RUNS FROM 
SEPTEMBER 1ST THROUGH NOVEMBER 30TH. 
THE AVERAGE TEMPERATURE FOR THE AUTUMN SEASON WAS 51.7 DEGREES...OR 3.6 DEGREES ABOVE 
NORMAL. THE NORMAL AVERAGE TEMPERATURE FOR THIS TIME PERIOD IS 48.1 DEGREES.
PERHAPS EVEN MORE ASTOUNDING...IS THE RUN OF ABOVE NORMAL TEMPERATURES SINCE THE MIDDLE 
OF OCTOBER...WHEN THE LAST SIGNIFICANT COOL (BELOW NORMAL) STRETCH HIT THE TWIN CITIES.
40 OUT OF THE LAST 42 DAYS IN THE TWIN CITIES HAVE BEEN ABOVE NORMAL.
FOR THE AUTUMN SEASON...73 OF THE 91 DAYS HAVE BEEN AT OR ABOVE NORMAL FOR DAILY 
AVERAGE TEMPERATURE. AS A COMPARISON...IN THE COLD SUMMER OF 2004...60 OF THE 
92 DAYS WERE BELOW NORMAL.

BELOW IS THE TABLE OF WARMEST AUTUMNS IN MINNEAPOLIS.
***WARMEST AUTUMNS IN MINNEAPOLIS HISTORY (1891-2004)
--------------------------------------------------------------------
1.  54.4  (1931)
2.  52.9  (1922/1953/1963)
5.  51.9  (2001)
6.  51.7  (1920/2004) *****
8.  51.6  (1998)
9.  51.5  (1994)
10. 51.4  (1948)

NIGHTTIME MINIMUMS HAVE BEEN ESPECIALLY WARM IN THE TWIN CITIES...
PARTLY ATTRIBUTED TO THE URBAN HEAT ISLAND WHICH HOLDS HEAT IN AT NIGHT. MORNING 
LOW TEMPERATURES AT OR BELOW FREEZING OCCUR 28 TIMES DURING
A NORMAL AUTUMN IN MINNEAPOLIS. THIS AUTUMN...MINNEAPOLIS HAD ONLY 19 DAYS
WHERE THE MORNING LOWS DIPPED 
TO 32 DEGREES OR BELOW. MINIMUM TEMPERATURES THIS AUTUMN AVERAGED 43.4 DEGREES...
WHICH RANKS 4TH AS THE WARMEST AVERAGE FOR DAILY MINIMUMS FOR THE AUTUMN SEASON. 
ON THE CONTRARY...DAYTIME MAXIMUMS AVERAGED 60.0 DEGREES...WHICH RANKS 14TH WARMEST 
ON RECORD...SO THE NIGHTTIME MINIMUMS ARE INDEED CONTRIBUTING TO THE WARMING MORE.
HOW DID WE GET HERE? SEPTEMBER GOT THE BALL ROLLING AS IT WAS TIED FOR THE 6TH
 WARMEST SEPTEMBER EVER. OCTOBER WAS A LITTLE WARMER THAN NORMAL...BUT NOT 
SUBSTANTIALLY...COMING IN AS THE 47TH WARMEST. NOVEMBER CONTINUED THAT TREND...
RANKING AS TIED FOR 19TH WARMEST ON RECORD.

THE REVERSAL BETWEEN SUMMER AND FALL OCCURRED IN PRECIPITATION AS WELL. AS 
MENTIONED ABOVE...THE SUMMER...WHILE BEING THE 14TH COOLEST...WAS ALSO THE 
18TH DRIEST AT 7.62 INCHES...OR 3.62 INCHES BELOW NORMAL. THE AUTUMN...WHILE 
BEING THE 6TH WARMEST...WAS 37TH WETTEST AT 7.44 INCHES...OR 1.04 INCHES ABOVE 
NORMAL.
ALSO OF INTEREST...IS THE LACK OF A MORNING LOW TEMPERATURE IN THE TEENS SO 
FAR AT TWIN CITIES INTERNATIONAL. SO FAR...THE LOWEST TEMPERATURE HAS BEEN 20 
DEGREES ON 11/12 AND 11/28. THE FIRST AVERAGE LOW IN THE TEENS COMES ON 11/10. 
BUT WE ARE NOWHERE CLOSE TO THE RECORD FOR THE LATEST. BACK IN 1931...THE FIRST 
LOW IN THE TEENS AT THE AIRPORT DIDN'T COME UNTIL 12/15.  

SNOW HAS ALSO BEEN LACKING IN THE TWIN CITIES SO FAR. BY DECEMBER 1ST
...ACCORDING TO 1971-2000 NORMALS...THERE SHOULD HAVE BEEN 10.6 INCHES OF 
SNOWFALL ALREADY. SEASON TO DATE...THERE HAS ONLY BEEN 0.8 INCHES OF SNOWFALL
AT THE NATIONAL WEATHER SERVICE OFFICE IN CHANHASSEN...THE OFFICIAL MEASURING
LOCATION FOR THE TWIN CITIES. ON AVERAGE...THE FIRST 1" SNOWFALL COMES ON 
11/18...WITH THE AVERAGE FIRST INCH OF SNOW DEPTH ON 11/21. HOWEVER...WE ARE
FAR FROM RECORDS ON BOTH. THE LATEST 1" SNOWFALL IN HISTORY CAME ON 1/9/45...AND 
THE LATEST 1" SNOW DEPTH CAME ON 1/1/13.  
THE LAST TIME THIS FLIP-FLOP OF SEASONAL EXTREMES OCCURRED WAS WHEN THE 
17TH COOLEST SUMMER AND 
15TH WARMEST FALL CAME BACK TO BACK IN THE YEAR OF 1958. IF THE WINTER OF 
DECEMBER 1958 TO FEBRUARY 1959 
(THE SEASON FOLLOWING THIS REVERSAL) IS ANY INDICATION OF WHAT LIES AHEAD 
FOR US...TWIN CITIES' RESIDENTS BETTER STOCK UP ON WARM CLOTHING. THE WINTER
(DEC-FEB) OF 1958-1959 SAW 33 MORNINGS AT OR BELOW ZERO (AVERAGE IS 27)...
WITH THE DEC-FEB TIMEFRAME AVERAGING MUCH COLDER THAN NORMAL. HOWEVER...THE
1958-1959 WINTER RANKED AS #5 FOR THE LEAST AMOUNT OF SNOW IN HISTORY WITH
ONLY 19.1 INCHES FALLING DURING THE METEOROLOGICAL WINTER. 

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URL: http://climate.umn.edu/doc/journal/mild_0409_11.htm
Last modified: December 1, 2004