Record envelope, standing records and threshold days for Waterloo (USC00338810), Ohio, United States, with 62 years of record.
Key Facts for Waterloo
Waterloo (USC00338810) is a weather station in Ohio, United States at 38.70 latitude and -82.47 longitude, 190 m (622 ft) above sea level.
The station reports from 1960 to 2021, 62 years of record.
1,464 records set at Waterloo still stand.
Records are tracked for prcp, snow, snwd: an element needs 30 years of data to be eligible.
Waterloo set a daily record precipitation of 39.4 mm (1.6 in) on 18 August 2021.
About the Station
Location: Ohio, United States, 38.70 latitude, -82.47 longitude.
Elevation: 190 m (622 ft).
Period of record: 1960 to 2021, 62 years.
Eligible elements: 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 Waterloo. 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 Waterloo, with 2026 drawn through them
Month
Highest record high
Lowest record low
2026 highest maximum
2026 lowest minimum
Jan
25.0 C (77.0 F)
-25.0 C (-13.0 F)
n/a
n/a
Feb
26.7 C (80.1 F)
-32.2 C (-26.0 F)
n/a
n/a
Mar
30.6 C (87.1 F)
-21.7 C (-7.1 F)
n/a
n/a
Apr
32.2 C (90.0 F)
-7.8 C (18.0 F)
n/a
n/a
May
34.4 C (93.9 F)
-3.9 C (25.0 F)
n/a
n/a
Jun
40.0 C (104.0 F)
2.8 C (37.0 F)
n/a
n/a
Jul
38.9 C (102.0 F)
8.3 C (46.9 F)
n/a
n/a
Aug
38.9 C (102.0 F)
7.8 C (46.0 F)
n/a
n/a
Sep
37.8 C (100.0 F)
1.1 C (34.0 F)
n/a
n/a
Oct
35.0 C (95.0 F)
-7.2 C (19.0 F)
n/a
n/a
Nov
28.3 C (82.9 F)
-13.9 C (7.0 F)
n/a
n/a
Dec
25.0 C (77.0 F)
-17.8 C (0.0 F)
n/a
n/a
Which Years Hold Standing Records
1,464 standing records
Year with most
1,464 records at Waterloo still stand. 2018 holds the most, with 79.
Standing records at Waterloo by the year they were set
Year set
Standing records
1995
6
1996
58
1997
62
1998
61
1999
67
2000
61
2001
63
2002
60
2003
29
2004
39
2005
59
2006
59
2007
77
2008
54
2009
57
2010
56
2011
59
2012
64
2013
40
2014
68
2015
70
2016
50
2017
51
2018
79
2019
40
2020
47
2021
28
All-Time Record Progression
2 new records
2 all-time records were set at Waterloo between 3 May 2010 and 5 March 2015. Each dot is a new record.
When Waterloo set new all-time records
Date
Kind
Detail
2010-05-03
Record daily precipitation
Record daily precipitation 121.9 mm (4.8 in)
2015-03-05
Record daily snowfall
Record daily snowfall 27.2 cm (10.7 in)
Wettest Day of Each Month
May: 121.9 mm (4.8 in)
The wettest day on record for each calendar month at Waterloo. The most was 121.9 mm (4.8 in) on 3 May 2010.
Record daily precipitation for each month at Waterloo
Month
Record daily precipitation (mm)
Date
Jan
72.4 mm (2.9 in)
24 January 2002
Feb
59.7 mm (2.4 in)
2 February 1981
Mar
83.8 mm (3.3 in)
2 March 1997
Apr
61.0 mm (2.4 in)
22 April 1972
May
121.9 mm (4.8 in)
3 May 2010
Jun
89.4 mm (3.5 in)
5 June 2008
Jul
103.6 mm (4.1 in)
31 July 1996
Aug
91.4 mm (3.6 in)
25 August 1999
Sep
99.1 mm (3.9 in)
27 September 1976
Oct
99.8 mm (3.9 in)
21 October 1985
Nov
48.8 mm (1.9 in)
20 November 1972
Dec
74.9 mm (2.9 in)
21 December 1978
Period of Record Coverage
1995 to 2021
Complete yearUnder 90 percent of days
27 years of record at Waterloo, 1995 to 2021. 4 years have data for under 90 percent of days and are left out of rankings: 1995, 2012, 2014, 2021.
Cooler than the station meanWarmer than the station mean
One stripe for each of 24 complete years at Waterloo, 1996 to 2020. Blue stripes are years cooler than the station's own mean of 11.9 C (53.4 F); red stripes are warmer. The coolest year was 2008, at 10.9 C (51.6 F), and the warmest was 1998, at 12.9 C (55.3 F). The strongest colour marks a difference of 1.1 C (2.0 F).
Annual mean temperature at Waterloo as warming stripes, 1996 to 2020
Year
Annual mean temperature
Difference from the station mean
1996
11.0 C
-0.87 C
1997
11.1 C
-0.72 C
1998
12.9 C
+1.08 C
1999
12.4 C
+0.49 C
2000
11.6 C
-0.27 C
2001
12.1 C
+0.19 C
2002
12.3 C
+0.47 C
2003
11.4 C
-0.44 C
2004
11.9 C
+0.06 C
2005
12.0 C
+0.12 C
2006
11.8 C
-0.07 C
2007
11.9 C
+0.08 C
2008
10.9 C
-0.98 C
2009
11.0 C
-0.90 C
2010
11.4 C
-0.47 C
2011
12.0 C
+0.17 C
2012
12.6 C
+0.77 C
2013
11.2 C
-0.68 C
2015
11.6 C
-0.25 C
2016
12.5 C
+0.62 C
2017
12.2 C
+0.33 C
2018
12.3 C
+0.39 C
2019
12.4 C
+0.52 C
2020
12.3 C
+0.45 C
This station does not have enough complete years (30 are needed) to fit a temperature trend.
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
1960 to 2021
Yearly extremes at Waterloo: the record and the median year
Measure
Record
Year of the record
Median year
Years with a value
Hottest day (TXx)
40.0 C (104.0 F)
2012
35.6 C (96.1 F)
27
Coldest night (TNn)
-32.2 C (-26.0 F)
2015
-18.3 C (-0.9 F)
27
Wettest day (Rx1day)
121.9 mm (4.8 in)
2010
63.5 mm (2.5 in)
55
Wettest five days (Rx5day)
164.4 mm (6.5 in)
1976
96.7 mm (3.8 in)
55
Longest dry spell (CDD)
25 days
1969
14 days
55
Hottest day (TXx)
The hottest day of the year at Waterloo, 1960 to 2021. The record is 40.0 C (104.0 F) in 2012, marked on the chart; the median year is 35.6 C (96.1 F).
Hottest day (TXx) at Waterloo by year
Year
Hottest day (TXx)
1960
n/a
1961
n/a
1963
n/a
1964
n/a
1965
n/a
1966
n/a
1967
n/a
1968
n/a
1969
n/a
1970
n/a
1971
n/a
1972
n/a
1973
n/a
1974
n/a
1975
n/a
1976
n/a
1977
n/a
1978
n/a
1979
n/a
1980
n/a
1981
n/a
1982
n/a
1983
n/a
1984
n/a
1985
n/a
1986
n/a
1987
n/a
1988
n/a
1995
18.3 C (64.9 F)
1996
33.3 C (91.9 F)
1997
33.9 C (93.0 F)
1998
36.1 C (97.0 F)
1999
38.3 C (100.9 F)
2000
33.3 C (91.9 F)
2001
34.4 C (93.9 F)
2002
37.2 C (99.0 F)
2003
33.3 C (91.9 F)
2004
32.2 C (90.0 F)
2005
37.2 C (99.0 F)
2006
35.6 C (96.1 F)
2007
38.9 C (102.0 F)
2008
33.9 C (93.0 F)
2009
33.3 C (91.9 F)
2010
36.7 C (98.1 F)
2011
37.8 C (100.0 F)
2012
40.0 C (104.0 F)
2013
34.4 C (93.9 F)
2014
35.0 C (95.0 F)
2015
33.9 C (93.0 F)
2016
36.1 C (97.0 F)
2017
33.3 C (91.9 F)
2018
35.6 C (96.1 F)
2019
36.1 C (97.0 F)
2020
36.7 C (98.1 F)
2021
35.6 C (96.1 F)
Coldest night (TNn)
The coldest night of the year at Waterloo, 1960 to 2021. The record is -32.2 C (-26.0 F) in 2015, marked on the chart; the median year is -18.3 C (-0.9 F).
Coldest night (TNn) at Waterloo by year
Year
Coldest night (TNn)
1960
n/a
1961
n/a
1963
n/a
1964
n/a
1965
n/a
1966
n/a
1967
n/a
1968
n/a
1969
n/a
1970
n/a
1971
n/a
1972
n/a
1973
n/a
1974
n/a
1975
n/a
1976
n/a
1977
n/a
1978
n/a
1979
n/a
1980
n/a
1981
n/a
1982
n/a
1983
n/a
1984
n/a
1985
n/a
1986
n/a
1987
n/a
1988
n/a
1995
-14.4 C (6.1 F)
1996
-30.0 C (-22.0 F)
1997
-17.8 C (0.0 F)
1998
-13.3 C (8.1 F)
1999
-17.2 C (1.0 F)
2000
-20.0 C (-4.0 F)
2001
-17.8 C (0.0 F)
2002
-16.1 C (3.0 F)
2003
-18.3 C (-0.9 F)
2004
-22.2 C (-8.0 F)
2005
-18.9 C (-2.0 F)
2006
-18.3 C (-0.9 F)
2007
-22.2 C (-8.0 F)
2008
-18.9 C (-2.0 F)
2009
-21.1 C (-6.0 F)
2010
-19.4 C (-2.9 F)
2011
-17.8 C (0.0 F)
2012
-11.1 C (12.0 F)
2013
-14.4 C (6.1 F)
2014
-25.0 C (-13.0 F)
2015
-32.2 C (-26.0 F)
2016
-21.7 C (-7.1 F)
2017
-16.7 C (1.9 F)
2018
-22.8 C (-9.0 F)
2019
-22.2 C (-8.0 F)
2020
-12.2 C (10.0 F)
2021
-17.2 C (1.0 F)
Wettest day (Rx1day)
The wettest day of the year at Waterloo, 1960 to 2021. The record is 121.9 mm (4.8 in) in 2010, marked on the chart; the median year is 63.5 mm (2.5 in).
Wettest day (Rx1day) at Waterloo by year
Year
Wettest day (Rx1day)
1960
61.7 mm (2.4 in)
1961
47.8 mm (1.9 in)
1963
43.7 mm (1.7 in)
1964
27.2 mm (1.1 in)
1965
48.3 mm (1.9 in)
1966
39.4 mm (1.6 in)
1967
63.5 mm (2.5 in)
1968
44.5 mm (1.8 in)
1969
88.9 mm (3.5 in)
1970
51.3 mm (2.0 in)
1971
64.8 mm (2.6 in)
1972
61.0 mm (2.4 in)
1973
38.1 mm (1.5 in)
1974
57.4 mm (2.3 in)
1975
47.0 mm (1.9 in)
1976
99.1 mm (3.9 in)
1977
39.4 mm (1.6 in)
1978
74.9 mm (2.9 in)
1979
66.0 mm (2.6 in)
1980
68.6 mm (2.7 in)
1981
59.7 mm (2.4 in)
1982
63.5 mm (2.5 in)
1983
77.0 mm (3.0 in)
1984
43.2 mm (1.7 in)
1985
99.8 mm (3.9 in)
1986
62.2 mm (2.4 in)
1987
68.6 mm (2.7 in)
1988
35.6 mm (1.4 in)
1995
36.6 mm (1.4 in)
1996
103.6 mm (4.1 in)
1997
83.8 mm (3.3 in)
1998
82.6 mm (3.3 in)
1999
91.4 mm (3.6 in)
2000
83.3 mm (3.3 in)
2001
45.0 mm (1.8 in)
2002
72.4 mm (2.9 in)
2003
43.7 mm (1.7 in)
2004
97.3 mm (3.8 in)
2005
72.1 mm (2.8 in)
2006
52.8 mm (2.1 in)
2007
52.8 mm (2.1 in)
2008
89.4 mm (3.5 in)
2009
79.0 mm (3.1 in)
2010
121.9 mm (4.8 in)
2011
95.5 mm (3.8 in)
2012
65.0 mm (2.6 in)
2013
51.6 mm (2.0 in)
2014
67.6 mm (2.7 in)
2015
43.4 mm (1.7 in)
2016
41.1 mm (1.6 in)
2017
71.6 mm (2.8 in)
2018
69.9 mm (2.8 in)
2019
66.0 mm (2.6 in)
2020
50.8 mm (2.0 in)
2021
57.9 mm (2.3 in)
Wettest five days (Rx5day)
The wettest five days of the year at Waterloo, 1960 to 2021. The record is 164.4 mm (6.5 in) in 1976, marked on the chart; the median year is 96.7 mm (3.8 in).
Wettest five days (Rx5day) at Waterloo by year
Year
Wettest five days (Rx5day)
1960
71.9 mm (2.8 in)
1961
78.3 mm (3.1 in)
1963
63.5 mm (2.5 in)
1964
31.0 mm (1.2 in)
1965
74.2 mm (2.9 in)
1966
108.1 mm (4.3 in)
1967
116.8 mm (4.6 in)
1968
116.7 mm (4.6 in)
1969
90.4 mm (3.6 in)
1970
95.0 mm (3.7 in)
1971
101.9 mm (4.0 in)
1972
88.7 mm (3.5 in)
1973
70.3 mm (2.8 in)
1974
86.2 mm (3.4 in)
1975
94.5 mm (3.7 in)
1976
164.4 mm (6.5 in)
1977
100.6 mm (4.0 in)
1978
82.0 mm (3.2 in)
1979
137.6 mm (5.4 in)
1980
157.1 mm (6.2 in)
1981
71.3 mm (2.8 in)
1982
85.8 mm (3.4 in)
1983
142.7 mm (5.6 in)
1984
90.3 mm (3.6 in)
1985
145.5 mm (5.7 in)
1986
105.4 mm (4.1 in)
1987
116.4 mm (4.6 in)
1988
62.6 mm (2.5 in)
1995
62.5 mm (2.5 in)
1996
103.9 mm (4.1 in)
1997
147.9 mm (5.8 in)
1998
108.0 mm (4.3 in)
1999
96.7 mm (3.8 in)
2000
138.6 mm (5.5 in)
2001
136.2 mm (5.4 in)
2002
92.3 mm (3.6 in)
2003
102.4 mm (4.0 in)
2004
131.9 mm (5.2 in)
2005
112.5 mm (4.4 in)
2006
84.9 mm (3.3 in)
2007
74.7 mm (2.9 in)
2008
121.1 mm (4.8 in)
2009
117.8 mm (4.6 in)
2010
124.9 mm (4.9 in)
2011
129.9 mm (5.1 in)
2012
95.5 mm (3.8 in)
2013
88.4 mm (3.5 in)
2014
77.8 mm (3.1 in)
2015
100.9 mm (4.0 in)
2016
67.1 mm (2.6 in)
2017
88.6 mm (3.5 in)
2018
160.3 mm (6.3 in)
2019
93.4 mm (3.7 in)
2020
118.7 mm (4.7 in)
2021
79.0 mm (3.1 in)
Longest dry spell (CDD)
The longest dry spell of the year at Waterloo, 1960 to 2021. The record is 25 days in 1969, marked on the chart; the median year is 14 days.
Longest dry spell (CDD) at Waterloo by year
Year
Longest dry spell (CDD)
1960
21 days
1961
14 days
1963
13 days
1964
6 days
1965
19 days
1966
22 days
1967
21 days
1968
20 days
1969
25 days
1970
15 days
1971
16 days
1972
9 days
1973
16 days
1974
15 days
1975
12 days
1976
20 days
1977
14 days
1978
12 days
1979
15 days
1980
13 days
1981
23 days
1982
15 days
1983
18 days
1984
20 days
1985
17 days
1986
14 days
1987
18 days
1988
9 days
1995
11 days
1996
14 days
1997
14 days
1998
11 days
1999
18 days
2000
14 days
2001
18 days
2002
17 days
2003
14 days
2004
13 days
2005
15 days
2006
14 days
2007
18 days
2008
14 days
2009
13 days
2010
12 days
2011
13 days
2012
11 days
2013
11 days
2014
21 days
2015
12 days
2016
12 days
2017
21 days
2018
15 days
2019
11 days
2020
14 days
2021
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
24 years with a frost
Across 24 years with a frost, the median last spring frost at Waterloo falls on 5 May and the median first autumn frost on 17 October, which leaves a median of 163 days between them.
Frost dates and growing season at Waterloo
Measure
Median, all years
Earliest period
Recent period (1996 to 2020)
Recent against earliest
Fitted trend
Last spring frost
5 May
n/a
5 May
n/a
n/a
First autumn frost
17 October
n/a
17 October
n/a
n/a
Growing days
163 days
n/a
163 days
n/a
n/a
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
44 years, 1965 to 2020
A day with at least 64.1 mm (2.5 in) of rain is expected about once in 2 years. A day with at least 130.4 mm (5.1 in) of rain is expected about once in 100 years.
Rainfall return levels at Waterloo: the daily rain expected about once in a given number of years
Expected about once in
A day with at least
Note
2 years
64.1 mm (2.5 in)
5 years
83.5 mm (3.3 in)
10 years
95.7 mm (3.8 in)
25 years
110.3 mm (4.3 in)
50 years
120.6 mm (4.7 in)
Longer than the 44 years of record
100 years
130.4 mm (5.1 in)
Longer than the 44 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, 44 years of values from 1965 to 2020.
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: 121.9 mm (4.8 in) in 2010; 103.6 mm (4.1 in) in 1996; 99.8 mm (3.9 in) in 1985.
Download the Data
Data for Waterloo standing records by year: CSV or JSON. Field meanings are on the data page.
Data for Waterloo 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 2026-10-15 (15 October 2026). Records are computed by this site and are not official.