Record envelope, standing records and threshold days for Stevenson Dam (USC00368469), Pennsylvania, United States, with 58 years of record.
Key Facts for Stevenson Dam
Stevenson Dam (USC00368469) is a weather station in Pennsylvania, United States at 41.40 latitude and -78.02 longitude, 284 m (932 ft) above sea level.
The station reports from 1969 to 2026, 58 years of record.
1,464 records set at Stevenson Dam still stand.
Records are tracked for tmax, tmin, prcp, snow, snwd: an element needs 30 years of data to be eligible.
Stevenson Dam tied a daily record high minimum temperature of 20.0 C (68.0 F) on 7 August 2026.
About the Station
Location: Pennsylvania, United States, 41.40 latitude, -78.02 longitude.
Elevation: 284 m (932 ft).
Period of record: 1969 to 2026, 58 years.
Eligible elements: tmax, tmin, prcp, snow, snwd.
Daily Record Envelope and 2026
12 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 Stevenson Dam. The lines show the 2026 daily maximum and minimum. 12 days in 2026 matched or passed a record. Temperatures are in degrees Celsius.
Daily record high and record low at Stevenson Dam, with 2026 drawn through them
Month
Highest record high
Lowest record low
2026 highest maximum
2026 lowest minimum
Jan
19.4 C (66.9 F)
-30.0 C (-22.0 F)
10.0 C (50.0 F)
-22.2 C (-8.0 F)
Feb
22.2 C (72.0 F)
-27.8 C (-18.0 F)
11.7 C (53.1 F)
-24.4 C (-11.9 F)
Mar
28.3 C (82.9 F)
-23.9 C (-11.0 F)
23.9 C (75.0 F)
-10.0 C (14.0 F)
Apr
32.2 C (90.0 F)
-10.6 C (12.9 F)
30.0 C (86.0 F)
-6.7 C (19.9 F)
May
35.0 C (95.0 F)
-5.6 C (21.9 F)
33.3 C (91.9 F)
-1.7 C (28.9 F)
Jun
35.0 C (95.0 F)
0.0 C (32.0 F)
32.8 C (91.0 F)
3.9 C (39.0 F)
Jul
41.1 C (106.0 F)
3.9 C (39.0 F)
35.0 C (95.0 F)
10.0 C (50.0 F)
Aug
37.2 C (99.0 F)
3.9 C (39.0 F)
30.0 C (86.0 F)
9.4 C (48.9 F)
Sep
35.6 C (96.1 F)
-0.6 C (30.9 F)
31.7 C (89.1 F)
3.3 C (37.9 F)
Oct
31.7 C (89.1 F)
-7.8 C (18.0 F)
26.1 C (79.0 F)
1.7 C (35.1 F)
Nov
26.1 C (79.0 F)
-15.6 C (3.9 F)
n/a
n/a
Dec
21.7 C (71.1 F)
-25.0 C (-13.0 F)
n/a
n/a
Which Years Hold Standing Records
1,464 standing records
Year with most
1,464 records at Stevenson Dam still stand. 1988 holds the most, with 54.
Standing records at Stevenson Dam by the year they were set
Year set
Standing records
1969
7
1970
40
1971
33
1972
35
1973
20
1974
34
1975
20
1976
47
1977
40
1978
19
1979
45
1980
21
1981
19
1982
22
1983
24
1984
24
1985
21
1986
23
1987
14
1988
54
1989
40
1990
42
1991
34
1992
22
1993
25
1994
32
1995
41
1996
24
1997
13
1998
41
1999
22
2000
24
2001
23
2002
31
2003
10
2004
13
2005
24
2006
20
2007
30
2008
15
2009
18
2010
18
2011
22
2012
28
2013
15
2014
32
2015
39
2016
20
2017
20
2018
21
2019
13
2020
21
2021
16
2022
13
2023
18
2024
17
2025
22
2026
23
All-Time Record Progression
5 new records
5 all-time records were set at Stevenson Dam between 9 September 2004 and 17 December 2020. Each dot is a new record.
When Stevenson Dam set new all-time records
Date
Kind
Detail
2004-09-09
Record daily precipitation
Record daily precipitation 109.2 mm (4.3 in)
2004-09-18
Record daily precipitation
Record daily precipitation 129.5 mm (5.1 in)
2011-07-22
Record high maximum temperature
Record high maximum temperature 38.9 C (102.0 F)
2011-07-23
Record high maximum temperature
Record high maximum temperature 41.1 C (106.0 F)
2020-12-17
Record daily snowfall
Record daily snowfall 74.7 cm (29.4 in)
Wettest Day of Each Month
Sep: 129.5 mm (5.1 in)
The wettest day on record for each calendar month at Stevenson Dam. The most was 129.5 mm (5.1 in) on 18 September 2004.
Record daily precipitation for each month at Stevenson Dam
Month
Record daily precipitation (mm)
Date
Jan
56.9 mm (2.2 in)
25 January 2010
Feb
38.1 mm (1.5 in)
15 February 1984
Mar
50.3 mm (2.0 in)
4 March 1999
Apr
53.8 mm (2.1 in)
10 April 1998
May
46.0 mm (1.8 in)
19 May 1988
Jun
97.0 mm (3.8 in)
23 June 1972
Jul
70.6 mm (2.8 in)
17 July 2020
Aug
81.3 mm (3.2 in)
18 August 1994
Sep
129.5 mm (5.1 in)
18 September 2004
Oct
93.2 mm (3.7 in)
21 October 1995
Nov
88.9 mm (3.5 in)
28 November 1993
Dec
87.6 mm (3.4 in)
1 December 2010
Period of Record Coverage
1969 to 2026
Complete yearUnder 90 percent of days
58 years of record at Stevenson Dam, 1969 to 2026. 4 years have data for under 90 percent of days and are left out of rankings: 1969, 1987, 1998, 2026.
Cooler than the station meanWarmer than the station mean
One stripe for each of 47 complete years at Stevenson Dam, 1970 to 2025. Blue stripes are years cooler than the station's own mean of 9.1 C (48.3 F); red stripes are warmer. The coolest year was 1995, at 7.1 C (44.8 F), and the warmest was 2012, at 11.0 C (51.7 F). The strongest colour marks a difference of 2.0 C (3.6 F).
Annual mean temperature at Stevenson Dam as warming stripes, 1970 to 2025
Year
Annual mean temperature
Difference from the station mean
1970
8.8 C
-0.26 C
1971
8.9 C
-0.21 C
1974
8.5 C
-0.55 C
1975
9.1 C
+0.03 C
1976
8.0 C
-1.12 C
1977
8.6 C
-0.44 C
1979
8.6 C
-0.50 C
1980
8.4 C
-0.68 C
1981
8.6 C
-0.45 C
1982
8.8 C
-0.31 C
1984
9.1 C
-0.03 C
1988
8.8 C
-0.28 C
1989
8.2 C
-0.85 C
1990
10.1 C
+1.06 C
1991
10.0 C
+0.88 C
1992
8.5 C
-0.58 C
1993
8.6 C
-0.45 C
1994
7.4 C
-1.65 C
1995
7.1 C
-1.99 C
1996
8.6 C
-0.50 C
1997
8.5 C
-0.63 C
2000
9.0 C
-0.04 C
2001
9.7 C
+0.66 C
2002
9.8 C
+0.69 C
2003
8.5 C
-0.59 C
2004
9.4 C
+0.30 C
2005
9.9 C
+0.81 C
2006
10.8 C
+1.68 C
2007
9.6 C
+0.54 C
2008
9.1 C
+0.00 C
2009
8.9 C
-0.14 C
2010
10.0 C
+0.91 C
2011
10.0 C
+0.91 C
2012
11.0 C
+1.88 C
2013
9.0 C
-0.13 C
2014
7.7 C
-1.34 C
2015
8.6 C
-0.51 C
2016
9.3 C
+0.25 C
2017
9.1 C
+0.03 C
2018
8.6 C
-0.50 C
2019
8.6 C
-0.51 C
2020
9.4 C
+0.28 C
2021
10.2 C
+1.11 C
2022
9.2 C
+0.14 C
2023
10.3 C
+1.18 C
2024
10.6 C
+1.52 C
2025
9.4 C
+0.34 C
The annual mean temperature here has risen by 0.2 C (0.1 to 0.3) per decade over 1970 to 2025. In Fahrenheit: 0.4 F (0.1 to 0.6) per decade. The slope is a straight line fitted to 47 complete years; the brackets give its 95 percent interval.
Fitted temperature trends per decade at Stevenson Dam
Measure
Per decade (C)
Per decade (F)
Period
Complete years
Reading
Annual mean temperature
0.2 C (0.1 to 0.3) per decade
0.4 F (0.1 to 0.6) per decade
1970 to 2025
47
Rise
Mean daily maximum
0.17 C (0.02 to 0.32) per decade
0.30 F (0.04 to 0.57) per decade
1970 to 2025
47
Rise
Mean daily minimum
0.2 C (0.1 to 0.4) per decade
0.4 F (0.2 to 0.7) per decade
1970 to 2025
47
Rise
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
1969 to 2026
Yearly extremes at Stevenson Dam: the record and the median year
Measure
Record
Year of the record
Median year
Years with a value
Hottest day (TXx)
41.1 C (106.0 F)
2011
33.9 C (93.0 F)
58
Coldest night (TNn)
-30.0 C (-22.0 F)
1994
-22.2 C (-8.0 F)
58
Wettest day (Rx1day)
129.5 mm (5.1 in)
2004
55.3 mm (2.2 in)
58
Wettest five days (Rx5day)
177.1 mm (7.0 in)
1972
89.8 mm (3.5 in)
58
Longest dry spell (CDD)
25 days
1991
15 days
58
Hottest day (TXx)
The hottest day of the year at Stevenson Dam, 1969 to 2026. The record is 41.1 C (106.0 F) in 2011, marked on the chart; the median year is 33.9 C (93.0 F).
Hottest day (TXx) at Stevenson Dam by year
Year
Hottest day (TXx)
1969
31.1 C (88.0 F)
1970
33.3 C (91.9 F)
1971
33.3 C (91.9 F)
1972
33.9 C (93.0 F)
1973
33.3 C (91.9 F)
1974
32.8 C (91.0 F)
1975
34.4 C (93.9 F)
1976
32.2 C (90.0 F)
1977
35.6 C (96.1 F)
1978
33.9 C (93.0 F)
1979
32.8 C (91.0 F)
1980
35.0 C (95.0 F)
1981
33.9 C (93.0 F)
1982
32.2 C (90.0 F)
1983
35.6 C (96.1 F)
1984
32.8 C (91.0 F)
1985
32.2 C (90.0 F)
1986
33.9 C (93.0 F)
1987
35.0 C (95.0 F)
1988
38.3 C (100.9 F)
1989
32.2 C (90.0 F)
1990
35.0 C (95.0 F)
1991
33.9 C (93.0 F)
1992
31.7 C (89.1 F)
1993
35.0 C (95.0 F)
1994
35.0 C (95.0 F)
1995
35.0 C (95.0 F)
1996
33.9 C (93.0 F)
1997
33.3 C (91.9 F)
1998
36.1 C (97.0 F)
1999
37.2 C (99.0 F)
2000
31.7 C (89.1 F)
2001
36.7 C (98.1 F)
2002
35.6 C (96.1 F)
2003
32.8 C (91.0 F)
2004
31.7 C (89.1 F)
2005
34.4 C (93.9 F)
2006
35.0 C (95.0 F)
2007
33.9 C (93.0 F)
2008
33.3 C (91.9 F)
2009
32.8 C (91.0 F)
2010
35.0 C (95.0 F)
2011
41.1 C (106.0 F)
2012
35.6 C (96.1 F)
2013
33.3 C (91.9 F)
2014
32.2 C (90.0 F)
2015
32.8 C (91.0 F)
2016
34.4 C (93.9 F)
2017
32.2 C (90.0 F)
2018
32.8 C (91.0 F)
2019
32.2 C (90.0 F)
2020
33.3 C (91.9 F)
2021
34.4 C (93.9 F)
2022
34.4 C (93.9 F)
2023
33.3 C (91.9 F)
2024
34.4 C (93.9 F)
2025
35.0 C (95.0 F)
2026
35.0 C (95.0 F)
Coldest night (TNn)
The coldest night of the year at Stevenson Dam, 1969 to 2026. The record is -30.0 C (-22.0 F) in 1994, marked on the chart; the median year is -22.2 C (-8.0 F).
Coldest night (TNn) at Stevenson Dam by year
Year
Coldest night (TNn)
1969
-21.7 C (-7.1 F)
1970
-23.3 C (-9.9 F)
1971
-24.4 C (-11.9 F)
1972
-21.1 C (-6.0 F)
1973
-24.4 C (-11.9 F)
1974
-18.3 C (-0.9 F)
1975
-21.1 C (-6.0 F)
1976
-24.4 C (-11.9 F)
1977
-26.1 C (-15.0 F)
1978
-23.3 C (-9.9 F)
1979
-27.8 C (-18.0 F)
1980
-23.3 C (-9.9 F)
1981
-27.2 C (-17.0 F)
1982
-26.1 C (-15.0 F)
1983
-22.2 C (-8.0 F)
1984
-29.4 C (-20.9 F)
1985
-26.1 C (-15.0 F)
1986
-18.9 C (-2.0 F)
1987
-25.6 C (-14.1 F)
1988
-21.1 C (-6.0 F)
1989
-25.0 C (-13.0 F)
1990
-20.0 C (-4.0 F)
1991
-18.3 C (-0.9 F)
1992
-17.8 C (0.0 F)
1993
-23.3 C (-9.9 F)
1994
-30.0 C (-22.0 F)
1995
-20.6 C (-5.1 F)
1996
-24.4 C (-11.9 F)
1997
-24.4 C (-11.9 F)
1998
-16.1 C (3.0 F)
1999
-18.9 C (-2.0 F)
2000
-21.1 C (-6.0 F)
2001
-13.9 C (7.0 F)
2002
-16.7 C (1.9 F)
2003
-20.0 C (-4.0 F)
2004
-23.9 C (-11.0 F)
2005
-22.2 C (-8.0 F)
2006
-13.9 C (7.0 F)
2007
-19.4 C (-2.9 F)
2008
-17.8 C (0.0 F)
2009
-27.2 C (-17.0 F)
2010
-20.0 C (-4.0 F)
2011
-24.4 C (-11.9 F)
2012
-15.6 C (3.9 F)
2013
-16.7 C (1.9 F)
2014
-26.7 C (-16.1 F)
2015
-27.2 C (-17.0 F)
2016
-20.0 C (-4.0 F)
2017
-18.9 C (-2.0 F)
2018
-23.3 C (-9.9 F)
2019
-22.2 C (-8.0 F)
2020
-15.6 C (3.9 F)
2021
-15.6 C (3.9 F)
2022
-23.3 C (-9.9 F)
2023
-15.6 C (3.9 F)
2024
-16.7 C (1.9 F)
2025
-22.2 C (-8.0 F)
2026
-24.4 C (-11.9 F)
Wettest day (Rx1day)
The wettest day of the year at Stevenson Dam, 1969 to 2026. The record is 129.5 mm (5.1 in) in 2004, marked on the chart; the median year is 55.3 mm (2.2 in).
Wettest day (Rx1day) at Stevenson Dam by year
Year
Wettest day (Rx1day)
1969
31.0 mm (1.2 in)
1970
41.4 mm (1.6 in)
1971
38.9 mm (1.5 in)
1972
97.0 mm (3.8 in)
1973
69.1 mm (2.7 in)
1974
43.9 mm (1.7 in)
1975
80.8 mm (3.2 in)
1976
65.3 mm (2.6 in)
1977
47.0 mm (1.9 in)
1978
61.5 mm (2.4 in)
1979
49.0 mm (1.9 in)
1980
53.1 mm (2.1 in)
1981
50.3 mm (2.0 in)
1982
35.6 mm (1.4 in)
1983
32.5 mm (1.3 in)
1984
89.2 mm (3.5 in)
1985
46.2 mm (1.8 in)
1986
40.9 mm (1.6 in)
1987
40.1 mm (1.6 in)
1988
47.2 mm (1.9 in)
1989
54.6 mm (2.1 in)
1990
50.0 mm (2.0 in)
1991
41.9 mm (1.6 in)
1992
66.8 mm (2.6 in)
1993
88.9 mm (3.5 in)
1994
81.3 mm (3.2 in)
1995
93.2 mm (3.7 in)
1996
64.0 mm (2.5 in)
1997
44.5 mm (1.8 in)
1998
53.8 mm (2.1 in)
1999
77.0 mm (3.0 in)
2000
49.5 mm (1.9 in)
2001
43.2 mm (1.7 in)
2002
57.2 mm (2.3 in)
2003
60.5 mm (2.4 in)
2004
129.5 mm (5.1 in)
2005
61.0 mm (2.4 in)
2006
55.9 mm (2.2 in)
2007
58.9 mm (2.3 in)
2008
33.0 mm (1.3 in)
2009
47.8 mm (1.9 in)
2010
87.6 mm (3.4 in)
2011
63.0 mm (2.5 in)
2012
56.1 mm (2.2 in)
2013
67.6 mm (2.7 in)
2014
38.9 mm (1.5 in)
2015
72.6 mm (2.9 in)
2016
53.3 mm (2.1 in)
2017
62.5 mm (2.5 in)
2018
52.1 mm (2.1 in)
2019
54.1 mm (2.1 in)
2020
70.6 mm (2.8 in)
2021
63.5 mm (2.5 in)
2022
63.8 mm (2.5 in)
2023
61.0 mm (2.4 in)
2024
60.7 mm (2.4 in)
2025
38.6 mm (1.5 in)
2026
52.6 mm (2.1 in)
Wettest five days (Rx5day)
The wettest five days of the year at Stevenson Dam, 1969 to 2026. The record is 177.1 mm (7.0 in) in 1972, marked on the chart; the median year is 89.8 mm (3.5 in).
Wettest five days (Rx5day) at Stevenson Dam by year
Year
Wettest five days (Rx5day)
1969
49.1 mm (1.9 in)
1970
83.4 mm (3.3 in)
1971
60.0 mm (2.4 in)
1972
177.1 mm (7.0 in)
1973
87.1 mm (3.4 in)
1974
83.3 mm (3.3 in)
1975
135.2 mm (5.3 in)
1976
90.7 mm (3.6 in)
1977
74.2 mm (2.9 in)
1978
89.7 mm (3.5 in)
1979
74.2 mm (2.9 in)
1980
64.0 mm (2.5 in)
1981
82.6 mm (3.3 in)
1982
72.0 mm (2.8 in)
1983
63.5 mm (2.5 in)
1984
105.7 mm (4.2 in)
1985
71.8 mm (2.8 in)
1986
79.6 mm (3.1 in)
1987
58.9 mm (2.3 in)
1988
68.8 mm (2.7 in)
1989
99.8 mm (3.9 in)
1990
91.2 mm (3.6 in)
1991
64.3 mm (2.5 in)
1992
119.9 mm (4.7 in)
1993
89.9 mm (3.5 in)
1994
170.7 mm (6.7 in)
1995
94.5 mm (3.7 in)
1996
105.2 mm (4.1 in)
1997
95.0 mm (3.7 in)
1998
64.9 mm (2.6 in)
1999
82.1 mm (3.2 in)
2000
106.2 mm (4.2 in)
2001
59.0 mm (2.3 in)
2002
68.9 mm (2.7 in)
2003
105.0 mm (4.1 in)
2004
132.3 mm (5.2 in)
2005
90.9 mm (3.6 in)
2006
125.0 mm (4.9 in)
2007
75.4 mm (3.0 in)
2008
66.8 mm (2.6 in)
2009
66.3 mm (2.6 in)
2010
118.4 mm (4.7 in)
2011
115.8 mm (4.6 in)
2012
99.1 mm (3.9 in)
2013
97.1 mm (3.8 in)
2014
66.8 mm (2.6 in)
2015
91.4 mm (3.6 in)
2016
89.6 mm (3.5 in)
2017
98.5 mm (3.9 in)
2018
125.5 mm (4.9 in)
2019
107.1 mm (4.2 in)
2020
79.2 mm (3.1 in)
2021
116.5 mm (4.6 in)
2022
97.3 mm (3.8 in)
2023
92.9 mm (3.7 in)
2024
108.7 mm (4.3 in)
2025
60.7 mm (2.4 in)
2026
65.2 mm (2.6 in)
Longest dry spell (CDD)
The longest dry spell of the year at Stevenson Dam, 1969 to 2026. The record is 25 days in 1991, marked on the chart; the median year is 15 days.
Longest dry spell (CDD) at Stevenson Dam by year
Year
Longest dry spell (CDD)
1969
9 days
1970
11 days
1971
24 days
1972
11 days
1973
15 days
1974
9 days
1975
18 days
1976
13 days
1977
14 days
1978
18 days
1979
12 days
1980
20 days
1981
15 days
1982
10 days
1983
21 days
1984
17 days
1985
14 days
1986
15 days
1987
23 days
1988
17 days
1989
22 days
1990
13 days
1991
25 days
1992
16 days
1993
11 days
1994
14 days
1995
25 days
1996
13 days
1997
21 days
1998
16 days
1999
14 days
2000
15 days
2001
16 days
2002
20 days
2003
17 days
2004
14 days
2005
16 days
2006
17 days
2007
14 days
2008
15 days
2009
12 days
2010
18 days
2011
18 days
2012
10 days
2013
11 days
2014
15 days
2015
12 days
2016
15 days
2017
19 days
2018
14 days
2019
11 days
2020
15 days
2021
16 days
2022
15 days
2023
22 days
2024
16 days
2025
16 days
2026
12 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
47 years with a frost
Across 47 years with a frost, the median last spring frost at Stevenson Dam falls on 9 May and the median first autumn frost on 15 October, which leaves a median of 160 days between them.
Fitted over all years, the growing season changes by +1.7 days per decade at this station.
Frost dates and growing season at Stevenson Dam
Measure
Median, all years
Earliest period
Recent period (1994 to 2025)
Recent against earliest
Fitted trend
Last spring frost
9 May
n/a
10 May
n/a
-0.2 days per decade
First autumn frost
15 October
n/a
17 October
n/a
+1.5 days per decade
Growing days
160 days
n/a
161 days
n/a
+1.7 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
55 years, 1970 to 2025
A day with at least 56.0 mm (2.2 in) of rain is expected about once in 2 years. A day with at least 120.3 mm (4.7 in) of rain is expected about once in 100 years.
Rainfall return levels at Stevenson Dam: the daily rain expected about once in a given number of years
Expected about once in
A day with at least
Note
2 years
56.0 mm (2.2 in)
5 years
72.0 mm (2.8 in)
10 years
83.1 mm (3.3 in)
25 years
97.6 mm (3.8 in)
50 years
108.8 mm (4.3 in)
100 years
120.3 mm (4.7 in)
Longer than the 55 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, 55 years of values from 1970 to 2025.
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: 129.5 mm (5.1 in) in 2004; 97.0 mm (3.8 in) in 1972; 93.2 mm (3.7 in) in 1995.
Station Changes
2 suspected
2 changes were suspected in the annual mean temperature of Stevenson Dam, at 2004 and 2014. Each is measured against neighbouring stations.
Relative to 5 neighbouring stations, the station's annual mean temperature from 2004 ran 0.3 C (0.6 F) higher than in the years before (likely change).
Relative to 5 neighbouring stations, the station's annual mean temperature from 2014 ran 0.6 C (1.0 F) lower than in the years before (possible change).
Suspected changes in the annual mean temperature at Stevenson Dam, against neighbouring stations
Year
Shift (C)
Shift (F)
Strength
Neighbours
2004
+0.3
+0.6
likely
5
2014
-0.6
-1.0
possible
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 Stevenson Dam standing records by year: CSV or JSON. Field meanings are on the data page.
Data for Stevenson Dam 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.