Tornado Update for the U.S. and Nebraska, January 1-May 31, 2009

There were 665 reported Year 2009 U.S. tornadoes as of May 29, 2009 (black line in the following graph).  The Year 2009 total is approximately 50% of what the total was a year ago.  Note how the May 2009 line on the graph basically becomes horizontal during May 2009 indicating the scarcity of tornadoes this year in the U.S. during May.  The climatological peak month for tornadoes in the entire U.S. is the month of May (although the peak period in Nebraska is early June and late June in the northern portion of the High Plains) . Although we have passed the time of year which normally sees the most number tornadoes, it is not possible to predict what the rest of the season might bring in the way of tornadoes.  If the current trend continues, however, we would expect that the number of tornadoes this year will be well below last year's total for the Great Plains as well as Nebraska.,

U.S. Tornadoes, January 1, 2009 -May 31, 2009

One of the primary reasons that there has been a lack of tornadoes across the Plains has been the persistent drier than normal weather pattern stretching back to last Winter.  The next two maps show the extent of the current dry conditions.  Lincoln is currently the 7th driest May on record, and the period of January 1 through May 28 is the 3rd driest on record for Lincoln (out of 123 years of data, 1887-2009).  Omaha is a little better off, but still quite dry for the year.  Much of the area of the Great Plains is below normal precipitation (yellow, orange and red) and parts of the area are less than 50% of normal precipitation.  The Nebraska - Kansas tornado alley is moisture starved right now and until the gulf moisture returns, storms and tornadoes will be fewer than normal. 






 

 

Nebraska Tornadoes, January 1, 2009 -May 31, 2009 
January: none
February: none
March: 5 tornadoes (all on March 23)
April: 4 tornadoes (all on April 4)
May: 5 tornadoes,  4 on May 12, and 1 on May 23.

Total of 14 tornadoes so far in 2009.

 Note that the total number is based upon "reports" and due to multiple counting of the same tornado, the number is usually lower once the data are examined at the end of the season.  Therefore, the current total of 14 for this time period will probably be reduced later in the year.

The following two maps show the location of the May 2009 tornadoes in Nebraska

Here is May 12, 2009



Here is May 23, 2009

Here is an animation of all the May 2009 daily maps showing tornado reports (RED)

Nebraska Tornado Totals
 by Month and Year 1950-2008
YEAR
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
YEAR
TOTAL
2008 0 0 0 2 18 34 3 2
0
0
0
 0 2008 59
2007 0 0 16 5 14 3 2 5 1
0
0
0
 2007 46
2006
0
0
4
4
0
8
1
2
3
0
0
0
2006
22
2005
0
0
1
3
18
13
1
0
4
0
0
0
2005
40
2004
0
0
0
4
76
18
10
2
0
0
0
0
2004
110
2003
0
0
0
8
16
43
13
0
0
0
1
0
2003
81
2002
0
0
0
2
8
3
8
7
0
0
0
0
2002
28
2001
0
0
0
14
6
14
13
1
3
11
0
0
2001
62
2000
0
0
0
5
10
21
6
0
0
18
1
0
2000
61
1999
0
0
0
17
24
48
4
4
5
0
0
0
1999
102
1998
0
0
0
0
17
28
10
0
0
10
0
0
1998
65
1997
0
0
0
1
5
11
3
10
0
0
0
0
1997
30
1996
0
0
0
0
12
22
15
7
1
3
0
0
1996
60
1995
0
0
0
0
21
2
1
2
0
0
0
0
1995
26
1994
0
0
0
6
14
14
10
0
1
10
0
0
1994
55
1993
0
0
1
0
13
25
23
6
0
1
0
0
1993
69
1992
6
0
1
0
17
34
14
1
1
0
0
0
1992
74
1991
0
0
0
9
29
23
1
0
1
0
0
0
1991
63
1990
0
0
15
1
23
39
6
4
0
0
0
0
1990
88
1989
0
0
0
8
4
21
4
4
0
0
0
0
1989
41
1988
0
0
0
1
7
5
4
3
0
0
0
0
1988
20
1987
0
0
3
0
6
8
5
4
0
0
0
0
1987
26
1986
0
0
0
17
6
10
12
3
6
0
0
0
1986
54
1985
0
0
4
15
14
4
2
6
7
0
0
0
1985
52
1984
0
0
0
4
6
36
4
0
0
0
0
0
1984
50
1983
0
0
0
0
2
12
1
0
0
0
0
0
1983
15
1982
0
0
0
1
15
13
1
2
0
1
0
0
1982
33
1981
0
0
0
3
0
5
6
5
0
0
0
0
1981
19
1980
0
0
0
0
10
16
1
3
0
8
0
0
1980
38
1979
0
0
0
3
0
8
6
2
0
1
0
0
1979
20
1978
0
0
0
8
16
7
7
2
2
0
0
0
1978
42
1977
0
0
0
4
35
8
8
8
5
0
0
0
1977
68
1976
0
0
1
5
3
5
10
1
1
0
0
0
1976
26
1975
0
0
2
10
22
35
5
2
1
0
0
2
1975
79
1974
0
0
0
14
7
1
2
6
0
2
0
0
1974
32
1973
0
0
0
3
4
2
5
0
3
2
0
0
1973
19
1972
0
0
0
0
15
4
10
1
0
0
0
0
1972
30
1971
0
0
0
1
18
22
8
0
0
3
0
0
1971
52
1970
0
0
0
0
1
8
2
2
1
0
0
0
1970
14
1969
0
0
0
0
3
8
7
2
0
0
0
0
1969
20
1968
0
0
0
2
2
9
7
1
0
0
0
0
1968
21
1967
0
0
1
0
1
35
0
1
1
0
0
0
1967
39
1966
0
0
0
0
5
4
1
0
0
0
0
0
1966
10
1965
0
0
0
0
32
8
6
0
0
0
0
0
1965
46
1964
0
0
0
8
13
13
5
2
0
0
0
0
1964
41
1963
0
0
0
5
3
7
1
1
0
0
0
0
1963
17
1962
0
0
0
1
28
9
1
2
0
0
0
0
1962
41
1961
0
0
0
0
6
3
2
0
0
1
0
0
1961
12
1960
0
0
0
1
10
24
1
7
0
0
0
0
1960
43
1959
0
0
0
0
26
9
3
5
1
0
0
0
1959
44
1958
0
0
0
2
4
12
25
10
1
0
0
0
1958
54
1957
0
0
0
9
16
15
11
2
0
0
0
0
1957
53
1956
0
0
0
2
6
10
8
2
1
4
1
0
1956
34
1955
0
0
0
1
4
9
10
3
4
0
0
0
1955
31
1954
0
0
0
1
2
8
3
2
0
0
0
0
1954
16
1953
0
0
0
2
9
24
7
2
0
0
0
0
1953
44
1952
0
0
0
1
3
2
1
2
0
0
0
0
1952
9
1951
0
0
0
1
3
2
2
1
0
0
0
0
1951
9
1950
0
0
0
0
2
2
1
0
1
0
0
0
1950
6
ALL YEARS
 JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC
ALL YEARS
TOTAL
6
0
49
214
710
846
349
152
55
75
3
2
  
2461
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
  
ALL YEARS
MOST
6
0
15
17
76
48
25
10
7
18
1
2
  
110
YEAR
1992
--
1980
1999
2004
1999
1958
1997
1985
2000
1956
1975
  
2004
Totals
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
  
Annual
1971-2000
6
0
27
136
375
489
194
86
34
59
1
2
  
1409
1971-2008
6
0
48
178
531
625
245
105
45
70
2
2
  
1857
1950-2008
6
0
49
214
710
846
349
152
55
75
3
2
  
2461
 
Averages
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
  
Annual
1971-2000
0.2
0.0
0.9
4.5
12.5
16.3
6.5
2.9
1.1
2.0
0.0
0.1
  
47.0
1971-2008
0.2
0.0
1.39
4.7
14.0
16.5
6.5
2.8
1.2
1.9
0.1
0.1
  
48.9
1950-2008
0.1
0.0
0.8
3.6
12.0
14.3
5.9
2.6
0.9
1.3
0.1
0.0
  
41.7

Why are there three different averages listed?

1.  The 1971-2000 is the current standard 30-year average time period. 
A new 30-year average will be calculated for the 1981-2010 time period

2.  The second average includes the years since 2000.

3.  The third average, 1950-2008 is the average for the entire data set.  It is lower due to the inclusion of the early years when data were under-reported.
___________________________________________________________
Ken Dewey
University of Nebraska-Lincoln
Applied Climate Sciences Group
School of Natural Resources