Record envelope, standing records and threshold days for Decatur (USC00012207), Alabama, United States, with 90 years of record.
Key Facts for Decatur
Decatur (USC00012207) is a weather station in Alabama, United States at 34.58 latitude and -86.97 longitude, 177 m (581 ft) above sea level.
The station reports from 1880 to 1969, 90 years of record.
1,464 records set at Decatur still stand.
Records are tracked for tmax, tmin, prcp, snow, snwd: an element needs 30 years of data to be eligible.
Decatur set a daily record precipitation of 38.1 mm (1.5 in) on 25 May 1969.
About the Station
Location: Alabama, United States, 34.58 latitude, -86.97 longitude.
Elevation: 177 m (581 ft).
Period of record: 1880 to 1969, 90 years.
Eligible elements: tmax, tmin, prcp, snow, snwd.
Daily Record Envelope and 2026
0 days at or beyond a record
Record highRecord low2026 daily maximum2026 daily minimum
The band shows the record high and record low for each calendar day at Decatur. The lines show the 2026 daily maximum and minimum. 0 days in 2026 matched or passed a record. Temperatures are in degrees Celsius.
Daily record high and record low at Decatur, with 2026 drawn through them
Month
Highest record high
Lowest record low
2026 highest maximum
2026 lowest minimum
Jan
26.1 C (79.0 F)
-20.6 C (-5.1 F)
n/a
n/a
Feb
28.3 C (82.9 F)
-24.4 C (-11.9 F)
n/a
n/a
Mar
33.9 C (93.0 F)
-15.6 C (3.9 F)
n/a
n/a
Apr
33.3 C (91.9 F)
-3.3 C (26.1 F)
n/a
n/a
May
37.8 C (100.0 F)
1.1 C (34.0 F)
n/a
n/a
Jun
42.2 C (108.0 F)
6.7 C (44.1 F)
n/a
n/a
Jul
41.7 C (107.1 F)
11.1 C (52.0 F)
n/a
n/a
Aug
41.7 C (107.1 F)
11.1 C (52.0 F)
n/a
n/a
Sep
40.0 C (104.0 F)
2.8 C (37.0 F)
n/a
n/a
Oct
37.8 C (100.0 F)
-3.3 C (26.1 F)
n/a
n/a
Nov
30.0 C (86.0 F)
-16.1 C (3.0 F)
n/a
n/a
Dec
25.6 C (78.1 F)
-17.2 C (1.0 F)
n/a
n/a
Which Years Hold Standing Records
1,464 standing records
Year with most
1,464 records at Decatur still stand. 1902 holds the most, with 48.
Standing records at Decatur by the year they were set
Year set
Standing records
1894
2
1895
18
1896
23
1897
27
1898
22
1899
39
1900
12
1901
32
1902
48
1903
16
1904
18
1905
20
1906
19
1907
48
1908
30
1909
27
1910
19
1911
28
1912
24
1913
13
1914
27
1915
24
1916
21
1917
33
1918
34
1919
15
1920
11
1921
7
1922
13
1923
11
1924
18
1925
23
1926
21
1927
28
1928
16
1929
20
1930
21
1931
37
1932
23
1933
25
1934
12
1935
23
1936
33
1937
19
1938
16
1939
10
1940
18
1941
12
1942
11
1943
23
1944
9
1945
14
1946
13
1947
10
1948
12
1949
11
1950
23
1951
17
1952
12
1953
7
1954
24
1955
19
1956
11
1957
10
1958
20
1959
8
1960
14
1961
17
1962
19
1963
19
1964
15
1965
17
1966
17
1967
20
1968
16
All-Time Record Progression
3 new records
3 all-time records were set at Decatur between 18 October 1928 and 1 January 1964. Each dot is a new record.
When Decatur set new all-time records
Date
Kind
Detail
1928-10-18
Record daily precipitation
Record daily precipitation 162.6 mm (6.4 in)
1958-02-15
Record daily snowfall
Record daily snowfall 21.6 cm (8.5 in)
1964-01-01
Record daily snowfall
Record daily snowfall 30.5 cm (12.0 in)
Wettest Day of Each Month
Oct: 162.6 mm (6.4 in)
The wettest day on record for each calendar month at Decatur. The most was 162.6 mm (6.4 in) on 18 October 1928.
Record daily precipitation for each month at Decatur
Month
Record daily precipitation (mm)
Date
Jan
117.3 mm (4.6 in)
6 January 1950
Feb
98.0 mm (3.9 in)
1 February 1951
Mar
125.7 mm (4.9 in)
23 March 1929
Apr
111.3 mm (4.4 in)
6 April 1892
May
88.9 mm (3.5 in)
29 May 1912
Jun
77.7 mm (3.1 in)
4 June 1934
Jul
118.1 mm (4.6 in)
16 July 1950
Aug
100.3 mm (3.9 in)
22 August 1960
Sep
110.2 mm (4.3 in)
10 September 1946
Oct
162.6 mm (6.4 in)
18 October 1928
Nov
100.8 mm (4.0 in)
10 November 1891
Dec
123.7 mm (4.9 in)
29 December 1954
Period of Record Coverage
1894 to 1969
Complete yearUnder 90 percent of days
76 years of record at Decatur, 1894 to 1969. 7 years have data for under 90 percent of days and are left out of rankings: 1894, 1895, 1896, 1913, 1958, 1967, 1969.
Cooler than the station meanWarmer than the station mean
One stripe for each of 65 complete years at Decatur, 1897 to 1966. Blue stripes are years cooler than the station's own mean of 16.6 C (61.9 F); red stripes are warmer. The coolest year was 1912, at 15.1 C (59.1 F), and the warmest was 1938, at 18.2 C (64.8 F). The strongest colour marks a difference of 1.7 C (3.1 F).
Annual mean temperature at Decatur as warming stripes, 1897 to 1966
Year
Annual mean temperature
Difference from the station mean
1897
16.2 C
-0.36 C
1898
16.2 C
-0.44 C
1899
16.6 C
-0.02 C
1900
16.8 C
+0.23 C
1901
15.2 C
-1.41 C
1902
17.4 C
+0.82 C
1904
16.1 C
-0.50 C
1905
16.3 C
-0.33 C
1906
17.1 C
+0.49 C
1907
16.5 C
-0.08 C
1908
16.3 C
-0.25 C
1909
15.9 C
-0.73 C
1910
15.8 C
-0.76 C
1911
17.0 C
+0.36 C
1912
15.1 C
-1.53 C
1915
16.0 C
-0.62 C
1916
16.8 C
+0.24 C
1917
15.7 C
-0.92 C
1919
16.6 C
+0.04 C
1920
15.7 C
-0.93 C
1921
17.7 C
+1.09 C
1922
17.1 C
+0.49 C
1923
16.1 C
-0.48 C
1924
15.2 C
-1.42 C
1925
17.0 C
+0.44 C
1926
15.9 C
-0.70 C
1927
17.3 C
+0.70 C
1928
15.5 C
-1.11 C
1929
15.8 C
-0.84 C
1930
16.6 C
+0.00 C
1931
17.5 C
+0.91 C
1932
17.0 C
+0.40 C
1933
17.9 C
+1.26 C
1934
17.7 C
+1.08 C
1935
17.8 C
+1.25 C
1936
17.6 C
+0.98 C
1937
17.4 C
+0.77 C
1938
18.2 C
+1.64 C
1939
17.6 C
+1.03 C
1940
15.8 C
-0.77 C
1941
17.5 C
+0.91 C
1942
17.0 C
+0.36 C
1943
17.2 C
+0.63 C
1944
16.9 C
+0.35 C
1945
16.9 C
+0.35 C
1946
17.4 C
+0.82 C
1947
16.6 C
+0.00 C
1948
16.7 C
+0.11 C
1949
17.2 C
+0.58 C
1950
16.7 C
+0.08 C
1951
17.1 C
+0.53 C
1952
17.3 C
+0.74 C
1953
17.5 C
+0.93 C
1954
17.6 C
+0.98 C
1955
16.7 C
+0.15 C
1956
16.5 C
-0.14 C
1957
16.3 C
-0.27 C
1959
16.2 C
-0.43 C
1960
15.1 C
-1.51 C
1961
15.5 C
-1.05 C
1962
16.1 C
-0.50 C
1963
15.1 C
-1.46 C
1964
15.7 C
-0.85 C
1965
16.1 C
-0.50 C
1966
15.5 C
-1.10 C
The fitted trend in annual mean temperature here over 1897 to 1966 is 0.02 C (-0.08 to 0.12) per decade. The interval includes zero, so the trend is not clearly different from zero. In Fahrenheit: 0.04 F (-0.14 to 0.22) per decade. The slope is a straight line fitted to 65 complete years; the brackets give its 95 percent interval.
Fitted temperature trends per decade at Decatur
Measure
Per decade (C)
Per decade (F)
Period
Complete years
Reading
Annual mean temperature
0.02 C (-0.08 to 0.12) per decade
0.04 F (-0.14 to 0.22) per decade
1897 to 1966
65
Not clearly different from zero
Mean daily maximum
-0.01 C (-0.13 to 0.10) per decade
-0.02 F (-0.23 to 0.18) per decade
1897 to 1966
65
Not clearly different from zero
Mean daily minimum
0.1 C (-0.1 to 0.2) per decade
0.1 F (-0.1 to 0.3) per decade
1897 to 1966
65
Not clearly different from zero
A year is complete when all 12 months have at least 20 days of both daily maximum and daily minimum readings. The annual mean is the mean of the monthly means. The trend describes this one station over this period; it does not say what caused the change.
Extremes by Year
1880 to 1969
Yearly extremes at Decatur: the record and the median year
Measure
Record
Year of the record
Median year
Years with a value
Hottest day (TXx)
42.2 C (108.0 F)
1914
37.8 C (100.0 F)
76
Coldest night (TNn)
-24.4 C (-11.9 F)
1899
-12.2 C (10.0 F)
76
Wettest day (Rx1day)
162.6 mm (6.4 in)
1928
71.0 mm (2.8 in)
82
Wettest five days (Rx5day)
210.9 mm (8.3 in)
1969
115.8 mm (4.6 in)
81
Longest dry spell (CDD)
53 days
1924
20 days
80
Hottest day (TXx)
The hottest day of the year at Decatur, 1880 to 1969. The record is 42.2 C (108.0 F) in 1914, marked on the chart; the median year is 37.8 C (100.0 F).
Hottest day (TXx) at Decatur by year
Year
Hottest day (TXx)
1880
n/a
1881
n/a
1890
n/a
1891
n/a
1892
n/a
1893
n/a
1894
22.8 C (73.0 F)
1895
35.0 C (95.0 F)
1896
37.2 C (99.0 F)
1897
40.6 C (105.1 F)
1898
39.4 C (102.9 F)
1899
40.0 C (104.0 F)
1900
37.8 C (100.0 F)
1901
41.7 C (107.1 F)
1902
41.7 C (107.1 F)
1903
36.7 C (98.1 F)
1904
35.6 C (96.1 F)
1905
35.6 C (96.1 F)
1906
38.3 C (100.9 F)
1907
40.0 C (104.0 F)
1908
37.2 C (99.0 F)
1909
38.3 C (100.9 F)
1910
36.1 C (97.0 F)
1911
37.8 C (100.0 F)
1912
36.1 C (97.0 F)
1913
38.3 C (100.9 F)
1914
42.2 C (108.0 F)
1915
36.7 C (98.1 F)
1916
37.2 C (99.0 F)
1917
38.3 C (100.9 F)
1918
41.7 C (107.1 F)
1919
35.6 C (96.1 F)
1920
36.1 C (97.0 F)
1921
37.8 C (100.0 F)
1922
36.7 C (98.1 F)
1923
36.1 C (97.0 F)
1924
37.2 C (99.0 F)
1925
40.0 C (104.0 F)
1926
37.2 C (99.0 F)
1927
36.1 C (97.0 F)
1928
36.7 C (98.1 F)
1929
36.1 C (97.0 F)
1930
41.7 C (107.1 F)
1931
41.7 C (107.1 F)
1932
37.8 C (100.0 F)
1933
40.6 C (105.1 F)
1934
41.1 C (106.0 F)
1935
41.7 C (107.1 F)
1936
41.7 C (107.1 F)
1937
39.4 C (102.9 F)
1938
40.0 C (104.0 F)
1939
36.7 C (98.1 F)
1940
37.2 C (99.0 F)
1941
37.8 C (100.0 F)
1942
37.8 C (100.0 F)
1943
40.0 C (104.0 F)
1944
37.8 C (100.0 F)
1945
38.3 C (100.9 F)
1946
35.0 C (95.0 F)
1947
39.4 C (102.9 F)
1948
37.8 C (100.0 F)
1949
35.0 C (95.0 F)
1950
35.0 C (95.0 F)
1951
39.4 C (102.9 F)
1952
41.1 C (106.0 F)
1953
38.3 C (100.9 F)
1954
40.0 C (104.0 F)
1955
36.7 C (98.1 F)
1956
38.3 C (100.9 F)
1957
37.2 C (99.0 F)
1958
37.2 C (99.0 F)
1959
35.0 C (95.0 F)
1960
35.6 C (96.1 F)
1961
35.6 C (96.1 F)
1962
40.0 C (104.0 F)
1963
35.6 C (96.1 F)
1964
38.3 C (100.9 F)
1965
36.7 C (98.1 F)
1966
37.8 C (100.0 F)
1967
35.0 C (95.0 F)
1968
37.8 C (100.0 F)
1969
32.8 C (91.0 F)
Coldest night (TNn)
The coldest night of the year at Decatur, 1880 to 1969. The record is -24.4 C (-11.9 F) in 1899, marked on the chart; the median year is -12.2 C (10.0 F).
Coldest night (TNn) at Decatur by year
Year
Coldest night (TNn)
1880
n/a
1881
n/a
1890
n/a
1891
n/a
1892
n/a
1893
n/a
1894
-16.1 C (3.0 F)
1895
-18.9 C (-2.0 F)
1896
-13.3 C (8.1 F)
1897
-19.4 C (-2.9 F)
1898
-12.2 C (10.0 F)
1899
-24.4 C (-11.9 F)
1900
-13.3 C (8.1 F)
1901
-17.2 C (1.0 F)
1902
-8.3 C (17.1 F)
1903
-12.8 C (9.0 F)
1904
-10.0 C (14.0 F)
1905
-19.4 C (-2.9 F)
1906
-8.3 C (17.1 F)
1907
-9.4 C (15.1 F)
1908
-10.0 C (14.0 F)
1909
-12.8 C (9.0 F)
1910
-12.2 C (10.0 F)
1911
-15.0 C (5.0 F)
1912
-16.1 C (3.0 F)
1913
-5.6 C (21.9 F)
1914
-13.3 C (8.1 F)
1915
-5.6 C (21.9 F)
1916
-10.0 C (14.0 F)
1917
-14.4 C (6.1 F)
1918
-20.6 C (-5.1 F)
1919
-11.7 C (10.9 F)
1920
-10.0 C (14.0 F)
1921
-4.4 C (24.1 F)
1922
-6.7 C (19.9 F)
1923
-10.0 C (14.0 F)
1924
-16.7 C (1.9 F)
1925
-14.4 C (6.1 F)
1926
-8.3 C (17.1 F)
1927
-15.0 C (5.0 F)
1928
-16.1 C (3.0 F)
1929
-12.2 C (10.0 F)
1930
-13.9 C (7.0 F)
1931
-8.9 C (16.0 F)
1932
-8.9 C (16.0 F)
1933
-15.6 C (3.9 F)
1934
-12.8 C (9.0 F)
1935
-12.2 C (10.0 F)
1936
-17.2 C (1.0 F)
1937
-12.2 C (10.0 F)
1938
-7.8 C (18.0 F)
1939
-7.8 C (18.0 F)
1940
-19.4 C (-2.9 F)
1941
-6.7 C (19.9 F)
1942
-16.1 C (3.0 F)
1943
-11.1 C (12.0 F)
1944
-10.0 C (14.0 F)
1945
-11.7 C (10.9 F)
1946
-7.8 C (18.0 F)
1947
-11.1 C (12.0 F)
1948
-12.8 C (9.0 F)
1949
-7.2 C (19.0 F)
1950
-16.1 C (3.0 F)
1951
-16.1 C (3.0 F)
1952
-7.2 C (19.0 F)
1953
-9.4 C (15.1 F)
1954
-7.8 C (18.0 F)
1955
-11.1 C (12.0 F)
1956
-7.8 C (18.0 F)
1957
-11.1 C (12.0 F)
1958
-17.8 C (0.0 F)
1959
-13.9 C (7.0 F)
1960
-13.9 C (7.0 F)
1961
-11.7 C (10.9 F)
1962
-18.3 C (-0.9 F)
1963
-19.4 C (-2.9 F)
1964
-11.1 C (12.0 F)
1965
-14.4 C (6.1 F)
1966
-19.4 C (-2.9 F)
1967
-6.7 C (19.9 F)
1968
-10.6 C (12.9 F)
1969
-8.9 C (16.0 F)
Wettest day (Rx1day)
The wettest day of the year at Decatur, 1880 to 1969. The record is 162.6 mm (6.4 in) in 1928, marked on the chart; the median year is 71.0 mm (2.8 in).
Wettest day (Rx1day) at Decatur by year
Year
Wettest day (Rx1day)
1880
50.8 mm (2.0 in)
1881
50.8 mm (2.0 in)
1890
58.4 mm (2.3 in)
1891
100.8 mm (4.0 in)
1892
111.3 mm (4.4 in)
1893
95.0 mm (3.7 in)
1894
39.1 mm (1.5 in)
1895
84.6 mm (3.3 in)
1896
86.6 mm (3.4 in)
1897
113.0 mm (4.4 in)
1898
50.5 mm (2.0 in)
1899
110.5 mm (4.4 in)
1900
69.3 mm (2.7 in)
1901
67.8 mm (2.7 in)
1902
87.6 mm (3.4 in)
1903
56.9 mm (2.2 in)
1904
65.3 mm (2.6 in)
1905
64.0 mm (2.5 in)
1906
100.3 mm (3.9 in)
1907
67.3 mm (2.6 in)
1908
72.4 mm (2.9 in)
1909
55.4 mm (2.2 in)
1910
54.6 mm (2.1 in)
1911
95.5 mm (3.8 in)
1912
93.5 mm (3.7 in)
1913
59.7 mm (2.4 in)
1914
78.7 mm (3.1 in)
1915
70.9 mm (2.8 in)
1916
106.7 mm (4.2 in)
1917
90.7 mm (3.6 in)
1918
50.0 mm (2.0 in)
1919
84.3 mm (3.3 in)
1920
95.0 mm (3.7 in)
1921
58.9 mm (2.3 in)
1922
61.0 mm (2.4 in)
1923
76.2 mm (3.0 in)
1924
78.7 mm (3.1 in)
1925
41.9 mm (1.6 in)
1926
50.8 mm (2.0 in)
1927
50.8 mm (2.0 in)
1928
162.6 mm (6.4 in)
1929
125.7 mm (4.9 in)
1930
68.6 mm (2.7 in)
1931
88.9 mm (3.5 in)
1932
101.6 mm (4.0 in)
1933
46.0 mm (1.8 in)
1934
77.7 mm (3.1 in)
1935
75.4 mm (3.0 in)
1936
73.4 mm (2.9 in)
1937
66.3 mm (2.6 in)
1938
62.0 mm (2.4 in)
1939
80.0 mm (3.1 in)
1940
45.7 mm (1.8 in)
1941
48.0 mm (1.9 in)
1942
82.3 mm (3.2 in)
1943
62.5 mm (2.5 in)
1944
61.2 mm (2.4 in)
1945
71.1 mm (2.8 in)
1946
110.2 mm (4.3 in)
1947
47.2 mm (1.9 in)
1948
65.8 mm (2.6 in)
1949
75.2 mm (3.0 in)
1950
118.1 mm (4.6 in)
1951
98.0 mm (3.9 in)
1952
60.5 mm (2.4 in)
1953
63.0 mm (2.5 in)
1954
123.7 mm (4.9 in)
1955
60.5 mm (2.4 in)
1956
117.1 mm (4.6 in)
1957
80.0 mm (3.1 in)
1958
68.8 mm (2.7 in)
1959
62.5 mm (2.5 in)
1960
100.3 mm (3.9 in)
1961
68.1 mm (2.7 in)
1962
43.7 mm (1.7 in)
1963
65.3 mm (2.6 in)
1964
99.6 mm (3.9 in)
1965
58.4 mm (2.3 in)
1966
55.9 mm (2.2 in)
1967
109.7 mm (4.3 in)
1968
92.5 mm (3.6 in)
1969
72.9 mm (2.9 in)
Wettest five days (Rx5day)
The wettest five days of the year at Decatur, 1880 to 1969. The record is 210.9 mm (8.3 in) in 1969, marked on the chart; the median year is 115.8 mm (4.6 in).
Wettest five days (Rx5day) at Decatur by year
Year
Wettest five days (Rx5day)
1880
133.4 mm (5.3 in)
1881
n/a
1890
109.5 mm (4.3 in)
1891
118.3 mm (4.7 in)
1892
99.1 mm (3.9 in)
1893
136.9 mm (5.4 in)
1894
59.9 mm (2.4 in)
1895
95.6 mm (3.8 in)
1896
116.6 mm (4.6 in)
1897
176.1 mm (6.9 in)
1898
83.6 mm (3.3 in)
1899
176.6 mm (7.0 in)
1900
114.8 mm (4.5 in)
1901
133.6 mm (5.3 in)
1902
101.1 mm (4.0 in)
1903
89.4 mm (3.5 in)
1904
100.8 mm (4.0 in)
1905
96.3 mm (3.8 in)
1906
127.0 mm (5.0 in)
1907
91.2 mm (3.6 in)
1908
95.5 mm (3.8 in)
1909
93.7 mm (3.7 in)
1910
90.0 mm (3.5 in)
1911
183.7 mm (7.2 in)
1912
125.3 mm (4.9 in)
1913
52.6 mm (2.1 in)
1914
115.8 mm (4.6 in)
1915
89.8 mm (3.5 in)
1916
195.5 mm (7.7 in)
1917
136.0 mm (5.4 in)
1918
102.1 mm (4.0 in)
1919
135.8 mm (5.3 in)
1920
145.8 mm (5.7 in)
1921
111.5 mm (4.4 in)
1922
102.1 mm (4.0 in)
1923
84.9 mm (3.3 in)
1924
116.6 mm (4.6 in)
1925
91.7 mm (3.6 in)
1926
181.1 mm (7.1 in)
1927
83.6 mm (3.3 in)
1928
172.2 mm (6.8 in)
1929
146.3 mm (5.8 in)
1930
97.0 mm (3.8 in)
1931
108.8 mm (4.3 in)
1932
138.4 mm (5.4 in)
1933
72.4 mm (2.9 in)
1934
166.0 mm (6.5 in)
1935
109.8 mm (4.3 in)
1936
139.2 mm (5.5 in)
1937
99.6 mm (3.9 in)
1938
98.1 mm (3.9 in)
1939
125.0 mm (4.9 in)
1940
130.6 mm (5.1 in)
1941
79.9 mm (3.1 in)
1942
91.6 mm (3.6 in)
1943
101.9 mm (4.0 in)
1944
130.5 mm (5.1 in)
1945
123.1 mm (4.8 in)
1946
155.4 mm (6.1 in)
1947
126.1 mm (5.0 in)
1948
148.3 mm (5.8 in)
1949
180.5 mm (7.1 in)
1950
178.3 mm (7.0 in)
1951
174.0 mm (6.9 in)
1952
70.3 mm (2.8 in)
1953
90.2 mm (3.6 in)
1954
133.1 mm (5.2 in)
1955
140.5 mm (5.5 in)
1956
169.7 mm (6.7 in)
1957
209.6 mm (8.3 in)
1958
132.1 mm (5.2 in)
1959
100.6 mm (4.0 in)
1960
112.5 mm (4.4 in)
1961
151.6 mm (6.0 in)
1962
110.7 mm (4.4 in)
1963
90.1 mm (3.5 in)
1964
124.7 mm (4.9 in)
1965
109.3 mm (4.3 in)
1966
92.7 mm (3.6 in)
1967
151.8 mm (6.0 in)
1968
102.7 mm (4.0 in)
1969
210.9 mm (8.3 in)
Longest dry spell (CDD)
The longest dry spell of the year at Decatur, 1880 to 1969. The record is 53 days in 1924, marked on the chart; the median year is 20 days.
Longest dry spell (CDD) at Decatur by year
Year
Longest dry spell (CDD)
1880
n/a
1881
n/a
1890
43 days
1891
20 days
1892
33 days
1893
13 days
1894
12 days
1895
10 days
1896
14 days
1897
17 days
1898
20 days
1899
22 days
1900
14 days
1901
18 days
1902
24 days
1903
18 days
1904
29 days
1905
20 days
1906
22 days
1907
18 days
1908
17 days
1909
21 days
1910
17 days
1911
27 days
1912
20 days
1913
14 days
1914
24 days
1915
20 days
1916
20 days
1917
20 days
1918
21 days
1919
23 days
1920
40 days
1921
18 days
1922
18 days
1923
38 days
1924
53 days
1925
24 days
1926
19 days
1927
19 days
1928
30 days
1929
14 days
1930
34 days
1931
20 days
1932
14 days
1933
17 days
1934
13 days
1935
34 days
1936
18 days
1937
13 days
1938
19 days
1939
20 days
1940
20 days
1941
25 days
1942
33 days
1943
25 days
1944
31 days
1945
17 days
1946
17 days
1947
19 days
1948
19 days
1949
16 days
1950
27 days
1951
24 days
1952
30 days
1953
31 days
1954
22 days
1955
23 days
1956
19 days
1957
20 days
1958
27 days
1959
11 days
1960
13 days
1961
31 days
1962
22 days
1963
32 days
1964
21 days
1965
22 days
1966
14 days
1967
31 days
1968
21 days
1969
10 days
Each chart shows one value per year; the dot marks the record year. TXx is the hottest daily maximum, TNn the coldest daily minimum, Rx1day and Rx5day the largest one-day and five-day rain totals, and CDD the longest run of days with less than 1 mm of rain. A year with missing days can understate an extreme.
Frost Dates and Growing Season
65 years with a frost
Across 65 years with a frost, the median last spring frost at Decatur falls on 24 March and the median first autumn frost on 4 November, which leaves a median of 225 days between them.
In 1936 to 1966 the median growing season was 224 days. That is 4 days more than in 1897 to 1930.
Fitted over all years, the growing season changes by +1.4 days per decade at this station.
Frost dates and growing season at Decatur
Measure
Median, all years
Earliest period (1897 to 1930)
Recent period (1936 to 1966)
Recent against earliest
Fitted trend
Last spring frost
24 March
29 March
24 March
5 days earlier
-1.5 days per decade
First autumn frost
4 November
3 November
3 November
no change
-0.1 days per decade
Growing days
225 days
220 days
224 days
4 days more
+1.4 days per decade
A frost day is a day with a daily minimum at or below 0 C (32 F). The last spring frost and the first autumn frost are the last and first such days of the cold season, and growing days are the days between them. A negative trend for the last spring frost means it comes earlier.
Rainfall Return Levels
64 years, 1890 to 1968
A day with at least 72.9 mm (2.9 in) of rain is expected about once in 2 years. A day with at least 158.2 mm (6.2 in) of rain is expected about once in 100 years.
Rainfall return levels at Decatur: the daily rain expected about once in a given number of years
Expected about once in
A day with at least
Note
2 years
72.9 mm (2.9 in)
5 years
95.1 mm (3.7 in)
10 years
110.0 mm (4.3 in)
25 years
129.2 mm (5.1 in)
50 years
143.7 mm (5.7 in)
100 years
158.2 mm (6.2 in)
Longer than the 64 years of record
The levels come from a generalised extreme value (GEV) distribution fitted by L-moments to the wettest-day total of each year, 64 years of values from 1890 to 1968.
A return level is an estimate. It is least reliable for the long periods, 50 and 100 years, and for any period longer than the record behind the fit, where the fit has to reach past the largest day actually observed. It is not a forecast.
The largest wettest-day totals in the fit: 162.6 mm (6.4 in) in 1928; 125.7 mm (4.9 in) in 1929; 123.7 mm (4.9 in) in 1954.
Station Changes
2 suspected
2 changes were suspected in the annual mean temperature of Decatur, at 1930 and 1956. Each is measured against neighbouring stations.
Relative to 5 neighbouring stations, the station's annual mean temperature from 1930 ran 0.6 C (1.0 F) higher than in the years before (likely change).
Relative to 5 neighbouring stations, the station's annual mean temperature from 1956 ran 0.4 C (0.6 F) lower than in the years before (likely change).
Suspected changes in the annual mean temperature at Decatur, against neighbouring stations
Year
Shift (C)
Shift (F)
Strength
Neighbours
1930
+0.6
+1.0
likely
5
1956
-0.3
-0.6
likely
5
Possible change at the station (a move, a new instrument or a new site); the record is kept as measured. A "likely" change has a larger test statistic than a "possible" one. Neither says why the station differs from its neighbours. How changes are found, and the largest ones.
Download the Data
Data for Decatur standing records by year: CSV or JSON. Field meanings are on the data page.
Data for Decatur threshold days by year: CSV or JSON. Field meanings are on the data page.
Source: NOAA National Centers for Environmental Information, Global Historical Climatology Network Daily (GHCN-Daily). Records are computed by World Extreme Weather Monitor and are not official NOAA products. (US Government open data (NOAA NCEI)) Data as of 2026-10-14 (14 October 2026). Records are computed by this site and are not official.