First Day of Snow in Boulder


Revised based on new info

Graph | Dates: 1948-2004

Statistics from 1948-2001

First day of measurable snow (that is, greater than a trace) at official Boulder site

Note: statistics have been updated through 2001.
[Note- It is possible that in other locations in Boulder, snow fell earlier or later than the dates that went into these calculations. Also, it is possible that snow fell earlier at the official site but melted before a measurement was taken.]

earliest day of 1st snow:  Sep 12 (1974)
latest day:                Nov 26 (1978)

average:                   Oct 18

first quartile             Oct 4
median                     Oct 20
third quartile             Oct 31

standard deviation         18.2 days

plot of first day snow in Boulder


List first day of snow in Boulder 1948-present

1948   October   16
1949   October   19
1950   November   2 
1951   September 21
1952   October   14
1953   November   4 
1954   October   25
1955   October   23
1956   October   24
1957   October   25
1958   September 30
1959   September 29
1960   October   15
1961   October   29
1962   November  15
1963   October   31
1964   November  14
1965   September 20
1966   October   14
1967   October   29
1968   October    9
1969   October    3 
1970   September 25
1971   September 17
1972   October   30
1973   November   2 
1974   September 12
1975   October   23
1976   October   26
1977   November   8 
1978    missing*
1979   October   29
1980   October   27
1981   October   25
1982   October   19
1983   November   8 
1984   September 25
1985   September 28
1986   October   11
1987   November  15
1988   November  15
1989     missing
1990   October    8 
1991   October    4 
1992   November   2 
1993   September 13
1994   September 21
1995   September 21
1996   September 26
1997   October   24
1998   November   7
1999   September 28
2000   September 23
2001   October    5
2002   October   23
2003   October   30
2004   November   1
2005   November  15
2006   October   10 (1am)
2007   October   21
2008   October   13
2009   October   10
2010   November   9
2011   October   26
2012   October    5
2013   October    4
2014   September 12

*1978: The official data has it as Nov 26. However, there are believable reports that it snowed 3 times before that date; once several inches deep.
[Pages are for curiosity only; there are no guarantees that the data is correct.]