SUBJECT: Go Directly to November; Do Not Pass "Go",... Saint Cloud October 2002 weather summary  

FROM: Bob Weisman

Earth Sciences, St. Cloud State University

The calendar said October, but Saint Cloud’s weather more resembled November during the past month. According to statistics from the Saint Cloud Regional Airport, the average October 2002 temperature was 38.1 degrees, more than seven degrees below normal. These cold readings made October 2002 the second coldest October in 122 years of Saint Cloud temperature records and the coldest October in 77 years. Only October 1925 (35.8 degrees) had a colder October.

Even though below normal temperatures plagued Saint Cloud for nearly the entire month of October, the cold was especially penetrating during the second half of the month. From October 15 through the end of the month, the average high temperature was 37.1 degrees and the average low temperature was 24.9 degrees. Those temperatures are typical of mid-November, rather than the second half of October. Despite the cold, only October 24 went down as a record cold day. The record low temperature was broken with a low of 15 degrees and the record low mean temperature was tied (27 degrees).

The other part of October that seemed out of place was the snowfall. Snowstorms on the 17th and the 21st produced 6.4 inches in Saint Cloud. This snowfall was nearly 6 inches above normal and was the second highest October snowfall in the 102 years of Saint Cloud snowfall records. Only October 1936 (6.8 inches) produced more snow. Both the snowstorms on the 17th and the 21st produced daily record snowfalls. The storm on the 21st was the second greatest October snowstorm in Saint Cloud history. The large single-storm October snowfall happened on October 21 and 22, 1995, when 5.2 inches of wet snow were recorded. The Halloween Blizzard of 1991 does not hold the record for October snowfall since only 3.1 inches of the 13-inch total occurred before midnight on Halloween Night.

The combination of the snowstorms during the second half of the month and the heavy rains early in the month pushed the October 2002 precipitation total to 3.58 inches, more than an inch and a quarter above normal. However, unlike September, this total did not crack the top ten wettest Octobers in Saint Cloud history. October 1899, when nearly 8 inches of rain fell, was the wettest year. Record rainfall was recorded on October fourth when 1.59 inches fell. However, the extremely cold conditions during the second half of the month actually slowed down the rate of rain, as moist Gulf of Mexico air couldn’t get any further north than Missouri. The growing season precipitation (April 1-October 31) now has reached more than 31 inches, more than 9 inches above normal. This seven-month rainfall total is the highest in 16 years and the sixth highest on record. This stands in sharp contrast to the extremely dry conditions during the past two years.

Of course, the question I’ve had to face all month is: why? (followed quickly by: why us?) How did we go from more than three degrees above normal during September to such a cold October? Strong high pressure over British Columbia and the Yukon Territories forced the upper-level steering winds to make an abrupt shift during the first week of October. This shift to a northerly or northwesterly wind flow aloft maintained itself for almost the entire month. The result was the draining progressively colder air from the northern Canadian islands into southern Canada and Minnesota. During the last week, a chunk of the coldest air did move southward into the United States. This process gets rid of the cold air since there is more sunshine at our latitude.

What about the next month? There are elements of a warmer pattern as a strong storm track has developed over the southern United States during the past two weeks. Also, the steering winds tend not to set up in a single pattern for the fall, which is usually a time of many changes. If the Canadian high would weaken, we would have a chance of getting some of that milder air into our area. Unfortunately, that high is forecast to persist for most of the next week. In the meantime, even colder air has moved from the North Pole into extreme northern Canada. This is no guarantee that conditions will get worse, but I don’t see much warming coming over the next week. I certainly don’t see the mild fall conditions that were forecast for our part of the country at the end of the summer.

Another question I frequently have to field is: does this much snow early in the season mean we’re going to get clobbered with snow? My answer is: huh? I looked at the other nine years that had the heaviest October snowfall. The average seasonal snowfall of those nine other years was 54.0 inches, but there were two years with less than 30 inches, a year with nearly normal snowfall, and 6 years with more than 53 inches of snow. So, there is a slight tendency towards above normal snowfall, but it certainly isn’t clear. (See table below for the details).


Summary For October 2002                Oct 2002        Normal
Temperature (oF)
Average high temperature                46.3            56.3
Average low temperature                 30.7            34.3
Average temperature                     38.1%           45.3
Warmest high for this month             71 on the 1st
Coolest high for this month             31 on the 23th  
Mildest low for this month              51 on the 11th
Coldest low for this month              15 on the 24th (record low: see below)
Record Temperatures
Daily cold low:                         15 on the 24th (old record: 16 in 1960)
Daily cold mean:                        27 on the 24th (tied record set in 1933)
%Second coldest October in Saint Cloud records

Precipitation (in)
October                                 3.58            2.24
Greatest in 24 hours (Oct 2002)         1.59 on the 4th (set record; see below)
Total Growing Season Precip (Apr-Oct)  31.31           22.24
Daily Record Rainfall:                  1.59 on the 4th (old record: 1.25 inch in 1946)
 
Snowfall (in)
October                                 6.4*             0.5
Greatest in 24 hours (Oct 2002)         3.9 on the 21st (broke record; see below) 
Daily Record Snowfall:                  2.5 in on the 17th (no snow previously on Oct 17th)
Daily Record Snowfall:                  3.9 in on the 21st (old record: 0.2 inch in 1987) 
*Second snowiest October in Saint Cloud records

St. Cloud Temps--October   (122 Years; Avg = 46.7 F; Sdev =  3.8 F)

        WARMEST                          COLDEST

     58.2 F  1900                     	35.8 F  1925
     56.6 F  1947                     	38.5 F  2002 -2nd coldest on record
     56.5 F  1963                     	39.3 F  1887
     54.6 F  1914                     	39.6 F  1917
     54.2 F  1938                     	40.1 F  1976
     53.7 F  1953                     	40.4 F  1895
     53.1 F  1924                     	40.7 F  1896
     53.0 F  1910                     	40.8 F  1988
     52.6 F  1920                     	41.2 F  1959
     52.2 F  1956                     	41.5 F  1952

St. Cloud Snowfall--October   (102 Years; Avg =   0.7 In; Sdev =   1.4 In)

             SNOWIEST                           
       6.8 IN  1936-1937                  
       6.4 IN  2002-2003   -2nd snowiest on record
       6.0 IN  1995-1996
       4.1 IN  1959-1960
       4.0 IN  1969-1970
       3.8 IN  1919-1920
       3.5 IN  1916-1917
       3.2 IN  1951-1952
       3.1 IN  1991-1992
       2.5 IN  1932-1933

 

Seasonal Snowfall for the Years with the Most October Snow

Snow Season	October Snowfall (in)		Seasonal Snowfall (in)
1936-1937		6.8				84.5 (second snowiest in Saint Cloud records)
2002-2003		6.4				????
1959-1960		4.1				26.3
1969-1970		4.0				47.6
1919-1920		3.8				53.6
1916-1917		3.5				75.5 (4th snowiest in Saint Cloud records)
1951-1952		3.2				56.5
1991-1992		3.1				54.5
1932-1933		2.5				28.7

Growing Season Precip: Apr-Oct
AVG = 21.99 SDEV = 5.24; 113 YRS; 110 GOOD YRS

 Record high precipitation totals

  33.83 1905
  31.84 1965
  31.63 1903
  31.59 1986
  31.45 1897
  31.31 2002 - 6th wettest growing season on record
  30.10 1899
  30.05 1985
  29.93 1906
  29.87 1990
        
Record Low Precipitation Totals

  11.02 1976
  12.80 1910
  12.89 1922
  13.57 1992
  14.04 2000 - 5th driest growing season on record
  14.52 1996
  14.83 1931
  14.96 1988
  15.00 1948
  15.25 1930
 
  22.39 2001
        
PRECIP: JUN-OCT
 AVG = 16.29 SDEV = 4.63; 112 YRS; 109 GOOD YRS

   9.06 1950
   9.11 1893
   9.17 1976
   9.38 1910
   9.41 1936
   9.59 1992
   9.63 1894
   9.63 1922
   9.86 2001 - 9TH PLACE ALL TIME
  10.07 2000 - 10TH PLACE ALL TIME


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Last modified: November 1, 2002