Early and Late Season Tornado Events
While tornadoes can occur during any month of the year given the right combination of atmospheric parameters, the tables below illustrate that tornado activity in the Tri-State region is rare to non-existent during the colder months. The earliest tornado on record (spring season) occurred on March 8, 1992 when an EF0 tornado developed in Dundy county, Nebraska. Most of the early season tornadoes have occurred in late March. While tornado records since 1950 are fairly reliable, information prior to that is less certain. In his book, Significant Tornadoes 1680-1991, Thomas Grazulis extensively researched tornadoes prior to 1950, documenting significant tornadoes (EF2-EF5).
In the first table below, early season tornadoes are listed. Since the only accurate compilation of tornadoes prior to 1950 are those rated EF2 and above, there may in actuality be additional tornadoes which have occurred in March and April. All tornadoes prior to 1950 are shaded in yellow to highlight this fact. Event totals for these events are not given, since it is unknown what the total number of tornadoes may have been.
Earliest Tornadoes (Mar-Apr) in the Tri-State Area ... 1882-2018
#
|
Date
|
County
|
Num - FScale
|
Event Total
|
1
|
03/08/1992
|
Dundy
|
1-F0
|
1
|
2
|
03/13/1973
|
Sherman
|
1-F1
|
1
|
3
|
03/24/2007
|
Yuma
|
1-F0
|
1
|
4
|
03/25/1980
|
Cheyenne, CO
|
1-F1
|
1
|
5
|
03/25/1995
|
Wichita
|
1-F0
|
1
|
6
|
03/28/1981
|
Logan
Sheridan
|
1-F1
1-F1
|
2
|
7
|
03/28/1993
|
Decatur
Norton
|
1-F0
2-F1
|
3
|
8
|
03/28/2007
|
Cheyenne, KS-Dundy
Wallace
Decatur
Sherman
Greeley
Cheyenne, KS Sherman-Cheyenne, KS
*Greeley-Wallace
|
1-F1
3-F0
1-F0
5-F0
1-F0, 1-F1
1-F0, 1-F1
1-F2
1-F0/F1
|
16
|
9
|
03/31/1954
|
Yuma
|
1-F?
|
1
|
10 | 04/02/2015 | Cheyenne, CO | 1-F0 | 1 |
11
|
04/08/1978
|
Red Willow
|
1-F?
|
1
|
12 | 04/08/2013 |
Kit Carson
Dundy
|
1-F0
1-F1
|
2 |
13
|
04/10/2005
|
Graham
|
1-F0, 1-F1
|
2
|
14
|
04/12/1941
|
Sherman
Wallace
Dundy
|
1-F2
1-F3
2-F2
|
|
15
|
04/12/2012
|
Hitchcock
|
1-EF0
|
1
|
16
|
04/13/2010
|
Kit Carson
|
1-EF0
|
1
|
17
|
04/14/1998
|
Decatur
|
1-F0, 3-F1
|
4
|
18 | 04/17/2015 |
Yuma
Sherman
|
2-F0
1-F0
|
3 |
19 | 04/19/1957 | Hitchcock | 1-F1 | 1 |
20
|
04/19/1979
|
Graham
|
1-F2
|
1
|
21
|
04/19/1997
|
Logan
|
1-F0
|
1
|
22
|
04/20/1885
|
Decatur
|
1-F2
|
|
23
|
04/20/1974
|
Rawlins
|
1-F1
|
1
|
24 | 04/20/2014 |
Thomas
Rawlins
|
1-F0
1-F0
|
2 |
25
|
04/22/1957
|
Kit Carson
Hitchcock
|
1-F2
1-F?
|
2
|
26
|
04/22/2012
|
Cheyenne, CO
Gove
|
5-EF0
1-EF0
|
6
|
27
|
04/23/1922
|
Wichita
|
1-F2
|
|
28
|
04/23/1989
|
Norton
|
3-F0
|
3
|
29 | 04/24/2015 | Wichita | 1-F0 | 1 |
30 |
04/25/1882
|
Dundy
|
1-F2
|
|
31
|
04/25/1990
|
Gove
Red Willow
|
1-F0
1-F0
|
2
|
32
|
04/26/1938
|
Kit Carson
Graham
|
1-F2
1-F2
|
|
33
|
04/27/1912
|
Red Willow
|
1-F2
|
|
34
|
04/27/1958
|
Rawlins
|
1-F2
|
1
|
35 | 04/27/2017 | Sherman | 1-F0 | 1 |
36
|
04/28/1884
|
Decatur
|
1-F2
|
|
37
|
04/28/1940
|
Norton
|
2-F2
|
|
38
|
04/28/1947
|
Sheridan-Thomas
|
F3
|
|
39
|
04/29/1942
|
Decatur
|
F5
|
|
40
|
04/29/1997
|
Thomas
|
1-F0
|
1
|
41
|
04/30/1906
|
Decatur
|
F3
|
|
Yellow shading represents data prior to 1950 and only includes significant tornadoes (EF2+).
Since 1950, for dates April 30 or earlier, there have been 30 tornado days (producing 65 tornadoes).
Since 1882, for dates April 30 or earlier, there have been at least 41 tornado days.
*On March 28, 2007, a tornado developed in Greeley County before crossing the county line into Wallace County. The tornado was rated as an F0 in Greeley County and an F1 in Wallace County.
Late season tornado events are shown below. The only tornado on record in November in the Tri-State area occurred in Yuma county Colorado in 1922. That fact is interesting enough, but considering the tornado occurred at 9:30 in the morning makes the event even more noteworthy. Once again, only those tornadoes rated EF2 and above are included prior to 1950, and are highlighted in yellow.
Latest Tornadoes (Oct-Nov) in the Tri-State Area ... 1882-2018
#
|
Date
|
County
|
Num-F Scale
|
Event Total
|
1 | 11/16/2015 |
Gove
Gove-Sheridan
Norton
|
2-F0
1-F0
1-F0, 2-F1
|
6 |
2
|
11/04/1922
|
Yuma
|
1-F3
|
1
|
3
|
10/31/2000
|
Decatur
Rawlins
Sheridan-Thomas-Decatur
Sherman
Thomas
Wallace-Sherman
Red Willow
|
1-F1
1-F0
1-F0
2-F0, 1-F2
1-F0
1-F1
2-F0
|
10
|
4
|
10/29/1956
|
Thomas
|
1-F2
|
1
|
5
|
10/28/2000
|
Gove
Graham
Norton
Sheridan
|
2-F1
2-F0
1-F0
1-F0
|
6
|
6
|
10/20/1963
|
Yuma
|
1-F1
|
1
|
7
|
10/17/1971
|
Cheyenne, KS
Rawlins
Yuma
|
1-F2
1-F3
1-F2
|
3
|
8
|
10/11/1997
|
Kit Carson
|
1-F1
|
1
|
9
|
10/11/2008
|
Sherman
|
1-F0
|
1
|
10
|
10/08/1997
|
Kit Carson
Yuma
|
2-F0
2-F0
|
4
|
11
|
10/06/2011
|
Thomas
|
1-F1
|
1
|
12
|
10/05/1994
|
Cheyenne, CO
Kit Carson
|
1-F0
1-F0, 1-F1, 1-F2
|
4
|
13 | 10/02/2017 |
Greeley
Gove
|
1-F0
1-F0, 3-F1
|
5 |
14 | 10/01/2017 | Graham | 2-F0 | 2 |
Yellow shading represents data prior to 1950 and only includes significant tornadoes (EF2+).
Since 1950, for dates October 1 or later, there have been 13 tornado days, producing 45 tornadoes.
Since 1882, for dates October 1 or later, there have been at least 14 tornado days.
Updated: August 2019