The heat wave of August 31-September 3, 2011 was very unusual. There have been only 7 times since weather records began in 1871 that the temperature reached 99 degrees on 3 or more consecutive days. The last time this occurred was July 6-9, 1988. The only time this occurred later in the year was September 13-15, 1939.
The temperature has never exceeded 100 degrees during the month of September since weather records began in 1871. Previous to September 3, there had been only 5 times in September when the temperature reached 100 degrees...twice in both 1939 and 1953 and the last time on September 5, 1954.
The four-day heat wave of August 31-September 3 was the hottest for so late in the season since September 13-15, 1939. The number of 90-degree days during 2011 is 42 as of September 13. This is the most 90-degree days during a year since 1988. The 100 degree reading on September 3 was the second for 2011. The last time the temperature reached 100 degrees on 2 or more days in a year was in 1988.
The earlier heat wave of July 17-August 8, 2011 was also very unusual. This 23-day heat wave broke the previous record of 19 consecutive days of 90 degree weather set in August 1936. This 23 day period was the hottest of anytime since weather records began in 1871 except one...July 1936. The average temperature for the 25 day period from July 4-28, 1936 was 85.0 degrees. As indicated in the following table, the heat wave of July 1936 remains the hottest of record at Indianapolis, despite the fact that the temperature was only above 90 degrees for 15 consecutive days.
Indianapolis Area Extremes
Highest Average Average Temperature degrees F
Days: 1/1 - 12/31
Length of period: 23 days
Years: 1871-2011
Rank Value Ending Date
1 85.2 7/28/1936, 7/27/1936
3 84.9 7/26/1936
4 84.7 7/17-19/1936, 7/25/1936, 7/29/1936
9 84.6 7/24/1936
10 84.3 7/20/1936, 7/23/1936
12 84.2 7/21/1936, 7/22/1936
14 84.1 8/ 8/2011
What follows are other hot summer weather statistics...
...Last Occurrence of 95 degrees and Higher at Indianapolis...
102 degrees on August 16, 1988
103 degrees on July 15, 1988
104 degrees on July 14, 1954
106 degrees on July 14, 1936
The highest temperature recorded at the Indianapolis airport is 107 degrees on July 25, 1934. At this time the official weather station was located in downtown Indianapolis where the temperature reached 105 degrees.
...Last Occurrence of Low Temperature of 75 degrees and Higher at Indianapolis...
75 degrees on August 7, 2011
76 degrees on July 29, 2011
79 degrees on July 23, 2011
80 degrees on August 23, 1936
81 degrees on August 22, 1936
82 degrees on August 19, 1936
84 degrees on July 7, 1874
85 degrees on June 28, 1874
Indianapolis Area
Top 10 Occurrences of Consecutive Days with
Maximum Temperature 90 degrees F or higher
Years: 1871-2011
Rank # Days End Date
1 23 8/ 8/2011
2 19 8/26/1936
3 18 7/30/1901
4 15 7/17/1936
5 14 8/13/2007
6 14 7/24/1983
7 14 7/20/1980
8 14 7/ 6/1966
9 13 8/30/1983
10 13 7/31/1940
Year
Number of 90 Degree Days
1983
23
2007
22
1936
21
1995
20
1947
19
2010, 1988
16
1944, 1900
15
1955, 1940, 1881
14
1941, 1985
13
2011, 1918
12
2002, 1959, 1953 1916, 1896
11
Monthly Average
5.0
Year
Number of 90 Degree Days
1901
25
1983
22
1916
21
2011, 1919, 1893
20
1966, 1936, 1934
19
1914, 1887
18
1980, 1954, 1913
17
Monthly Average
5.2
Month
Average
Maximum
Year
April
0.0
1
1925, 1942
May
0.1
6
1941
June
2.7
18
1934, 1954
July
5.2
25
1901
August
5.0
23
1983
September
1.5
12
1891, 1897
October
0.1
2
2007
Annual
14.6
58
1983
1983
58
1936
55
1954
50
1988
49
1934
46
1953, 1941
45
1894
43
2011,1933, 1913, 1895
42
1931, 1914
41
1952, 1944, 1919
39
1901, 1887
38
2010, 2007, 1966
37
Annual Average
14.6
| 1936 | 31 |
| 1988 | 23 |
| 1887 | 19 |
| 1933 | 18 |
| 1934 | 17 |
| 2011, 1953 | 16 |
| 1983, 1954, 1941, 1930, 1914, 1913, 1901 | 14 |
| 1931 | 13 |
| 1881 | 12 |
| 1940, 1894 | 11 |
| 2010 | 10 |
| In 57 years since 1871 the temperature did not reach 95 degrees. | 0 |
| Year | Jun | Jul | Aug | Sep | Ann |
| 1936 | 0 | 9 | 3 | 0 | 12 |
| 1934 | 4 | 6 | 0 | 0 | 10 |
| 1988 | 1 | 3 | 1 | 0 | 5 |
| 1954 | 1 | 2 | 0 | 1 | 4 |
| 1953 | 1 | 0 | 0 | 2 | 3 |
| 1881 | 0 | 2 | 1 | 0 | 3 |
| 1887 | 0 | 3 | 0 | 0 | 3 |
| 1901 | 0 | 3 | 0 | 0 | 3 |
| 1930 | 0 | 3 | 0 | 0 | 3 |
| 1939 | 0 | 0 | 0 | 2 | 2 |
| 1895 | 1 | 0 | 1 | 0 | 2 |
| 1911 | 0 | 2 | 0 | 0 | 2 |
| 1916 | 0 | 2 | 0 | 0 | 2 |
| 2011 | 0 | 1 | 0 | 1 | 2 |
| 1918 | 0 | 0 | 1 | 0 | 1 |
| 1913 | 0 | 1 | 0 | 0 | 1 |
| 1914 | 0 | 1 | 0 | 0 | 1 |
| 1940 | 0 | 1 | 0 | 0 | 1 |
| 1941 | 0 | 1 | 0 | 0 | 1 |
| 1952 | 0 | 1 | 0 | 0 | 1 |
| 1980 | 0 | 1 | 0 | 0 | 1 |
| Record Total | 8 | 42 | 7 | 5 | 62 |
| Annual Average | 0.1 | 0.3 | 0.1 | 0 | 0.4 |
Indianapolis Area
Occurrences of 2 or more consecutive days with
Maximum Temperature 100 degrees F or higher
Years: 1871-2011
Rank # Days End Date
1 9 7/15/1936
2 6 7/25/1934
3 3 6/29/1934
4 2 7/ 9/1988
5 2 9/ 2/1953
6 2 9/15/1939
7 2 8/22/1936
8 2 7/28/1916
9 2 7/ 4/1911
10 2 7/22/1901
11 2 7/18/1887
12 2 7/11/1881
Statistics and Tables Updated at 8:30am EDT September 14, 2011.