Cold and Snowy October, Record Cold in Casper

 

Coldest October on Record in Casper
Top Ten Coldest and/or Snowiest October at Lander, Riverton and Rock Springs

 

November 3 - Casper experienced the coldest October on record (period of record 1939-2009) with a monthly average temperature 
of 37.0 degrees which was 8.7 degrees below normal. The lowest temperature for the month was 11 degrees on the 10th.
Several record lows were broken during the month: 22 degrees on the 3rd, 12 degrees on the 9th, 11 degrees on the 10th
and 16 degrees on the 11th.
Casper also recorded the seventh snowiest October on record with 13.8 inches, 6.7 inches above normal.  The maximum daily
snowfall of 5.2 inches fell on the 9th. The following are the top ten coldest and snowiest Octobers in Casper:

 Temperature graph of daily temperature range, normals and extremes for October 2009

Casper - Natrona County International Airport
Rank Average Temperature (F) Year
(Oct)
Period of Record 1939-2009 Rank

Snowfall
(Inches)

Year
(Oct)

1 37.0 2009   1 22.4 1949
2 37.8 1969   2 21.0 2003
3 38.2 2002   3 20.2 1998
4 40.1 1984   4 16.1 1986
5 41.0 1949   5 14.7 1994
6 41.1 1970   6 14.1 1996
7 41.8 1946   7 13.8 2009
8 42.8 1971   8 13.4 1995
9 43.7 1959   9 13.1 1971
10 43.8 1976   10 12.5 1969
Avg 45.7     Avg 7.1  

 

Lander experienced the third coldest October on record (period of record 1891-2009) with a monthly average temperature 
of 37.2 degrees which was 9.2 degrees below normal. The lowest temperature for the month was 10 degrees on the 10th.
Several record lows were broken during the month: 20 degrees on the 5th, 14 degrees on the 6th, 15 degrees on the 9th,
10 degrees on the 10th and 12 degrees on the
11th.

Lander also recorded the seventh snowiest October on record with 27.9 inches, or 19.2 inches above normal. The maximum daily
snowfall of 14.4 inches fell on the 4th. The following are the top ten coldest and snowiest Octobers in Lander:

 Temperature graph of daily temperature range, normals and extremes for October 2009

Lander - Hunt Field
Rank
Average Temperature (F)
Year
(Oct)
Period of Record 1891-2009
Rank

Snowfall
(Inches)

Year
(Oct)

1
33.1
1919

1
39.9
1971
2
37.1
1923

2
38.6
1961
3
37.2
2009

3
34.5
1920
4
37.5
1925

4
32.4
1969
5
37.8
1969

5
30.4
1919
6
38.6
1905

6
30.2
2008
7
39.3
1898

7
27.9
2009
8
39.4
2002

8
27.8
1949
9
39.5 1949

9
27.6
1928
10
39.6
1946

10
26.5
1966
Avg 46.4     Avg 8.7  

 

Riverton experienced the third coldest October on record (period of record 1907-2009) with a monthly average temperature of 38.2 degrees
which was 6.6 degrees below normal. The lowest temperature for the month was 6 degrees on the 10th. A couple of record lows were
broken during the month: 16 degrees on the 6th and 6 degrees on the 10th. The 6 degree reading was also a record low so early in

the season.

Riverton also recorded the fourth snowiest October on record with 19.7 inches, 17.2 inches above normal. The maximum daily
snowfall of 9.8 inches fell on the 4th. The following are the top ten coldest and snowiest Octobers in Riverton:

 

Riverton - Downtown
Rank
Average Temperature (F)
Year
(Oct)
Period of Record 1907-2009
Rank

Snowfall
(Inches)

Year
(Oct)

1
37.2
1919

1
23.5
1919
2
37.8
1925

2
23.0
1971
3
38.2
1969

3
22.0
1928
3
38.2
2009

4
19.7
2009
5
39.1
1923

5
17.1
1961
6
39.6
1970

6
15.0
1920
7
40.2
1984

7
13.6
2002
8
40.5
2002

8
12.6
2003
8
40.5
1971

9
12.2
2008
10
40.9 1949

10
12.0
1923
10 40.9 1932        
Avg 44.8     Avg 2.5  

 

Rock Springs experienced the second coldest October on record (period of record 1948-2009) with a monthly average temperature
of 37.6 degrees which was 5.9 degrees below normal. The lowest temperature for the month was 13 degrees on the 29th.
A couple of record lows were broken during the month: 15 degrees on the 9th and 14 degrees on the 10th.

The following are the top ten coldest and snowiest Octobers in Rock Springs:

Temperature graph of daily temperature range, normals and extremes for October 2009

Rock Springs - Sweetwater County Airport
Rank
Average Temperature (F)
Year
(Oct)
Period of Record 1948-2009
1
35.9
1969

2
37.6
2009

3
38.5
1949

3
38.5
1970

5
38.7
1984

6
39.7
1961

6
39.7
1981

6
39.7
2002

9
40.7
1971

10
41.3
1996

Avg 43.5    


Return to News Archive

USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.