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 Cloudís 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 couldnít 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 Iíve 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 donít see much warming coming over the next week. I certainly donít 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 weíre 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 isnít 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
Last modified: November 1, 2002