Record envelope, standing records and threshold days for McNary Dam (USC00455231), Washington, United States, with 54 years of record.
Key Facts for McNary Dam
McNary Dam (USC00455231) is a weather station in Washington, United States at 45.94 latitude and -119.30 longitude, 110 m (361 ft) above sea level.
The station reports from 1954 to 2007, 54 years of record.
1,464 records set at McNary Dam still stand.
Records are tracked for tmax, tmin, prcp, snow, snwd: an element needs 30 years of data to be eligible.
McNary Dam set a daily record precipitation of 0.5 mm (0.02 in) on 19 July 2007.
About the Station
Location: Washington, United States, 45.94 latitude, -119.30 longitude.
Elevation: 110 m (361 ft).
Period of record: 1954 to 2007, 54 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 McNary Dam. 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 McNary 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)
-22.2 C (-8.0 F)
n/a
n/a
Feb
21.1 C (70.0 F)
-21.7 C (-7.1 F)
n/a
n/a
Mar
26.1 C (79.0 F)
-11.1 C (12.0 F)
n/a
n/a
Apr
32.2 C (90.0 F)
-2.8 C (27.0 F)
n/a
n/a
May
40.0 C (104.0 F)
1.1 C (34.0 F)
n/a
n/a
Jun
41.1 C (106.0 F)
1.7 C (35.1 F)
n/a
n/a
Jul
43.3 C (109.9 F)
6.1 C (43.0 F)
n/a
n/a
Aug
43.9 C (111.0 F)
6.1 C (43.0 F)
n/a
n/a
Sep
39.4 C (102.9 F)
1.1 C (34.0 F)
n/a
n/a
Oct
30.6 C (87.1 F)
-6.7 C (19.9 F)
n/a
n/a
Nov
23.9 C (75.0 F)
-18.9 C (-2.0 F)
n/a
n/a
Dec
19.4 C (66.9 F)
-22.8 C (-9.0 F)
n/a
n/a
Which Years Hold Standing Records
1,464 standing records
Year with most
1,464 records at McNary Dam still stand. 1958 holds the most, with 56.
Standing records at McNary Dam by the year they were set
Year set
Standing records
1954
2
1955
54
1956
43
1957
44
1958
56
1959
32
1960
40
1961
33
1962
30
1963
26
1964
26
1965
30
1966
28
1967
50
1968
26
1969
33
1970
27
1971
41
1972
48
1973
26
1974
36
1975
28
1976
24
1977
33
1978
21
1979
17
1980
25
1981
12
1982
20
1983
31
1984
18
1985
44
1986
22
1987
40
1988
21
1989
23
1990
32
1991
15
1992
23
1993
37
1994
15
1995
30
1996
26
1997
8
1998
24
1999
20
2000
14
2001
16
2002
27
2003
30
2004
8
2005
6
2006
18
2007
5
All-Time Record Progression
1 new records
1 all-time records were set at McNary Dam between 15 January 1993 and 15 January 1993. Each dot is a new record.
When McNary Dam set new all-time records
Date
Kind
Detail
1993-01-15
Record snow depth
Record snow depth 30.5 cm (12.0 in)
Wettest Day of Each Month
Oct: 53.8 mm (2.1 in)
The wettest day on record for each calendar month at McNary Dam. The most was 53.8 mm (2.1 in) on 1 October 1957.
Record daily precipitation for each month at McNary Dam
Month
Record daily precipitation (mm)
Date
Jan
23.4 mm (0.9 in)
26 January 1975
Feb
17.8 mm (0.7 in)
1 February 1997
Mar
14.7 mm (0.6 in)
2 March 1957
Apr
28.7 mm (1.1 in)
21 April 1988
May
51.6 mm (2.0 in)
4 May 2007
Jun
16.5 mm (0.6 in)
6 June 2007
Jul
15.7 mm (0.6 in)
1 July 1989
Aug
22.4 mm (0.9 in)
14 August 1979
Sep
21.1 mm (0.8 in)
26 September 1982
Oct
53.8 mm (2.1 in)
1 October 1957
Nov
42.7 mm (1.7 in)
19 November 1996
Dec
25.9 mm (1.0 in)
22 December 1964
Period of Record Coverage
1954 to 2007
Complete yearUnder 90 percent of days
54 years of record at McNary Dam, 1954 to 2007. 5 years have data for under 90 percent of days and are left out of rankings: 1954, 1981, 1982, 2005, 2007.
Cooler than the station meanWarmer than the station mean
One stripe for each of 46 complete years at McNary Dam, 1955 to 2004. Blue stripes are years cooler than the station's own mean of 12.3 C (54.1 F); red stripes are warmer. The coolest year was 1993, at 10.5 C (50.9 F), and the warmest was 1958, at 14.1 C (57.4 F). The strongest colour marks a difference of 1.9 C (3.4 F).
Annual mean temperature at McNary Dam as warming stripes, 1955 to 2004
Year
Annual mean temperature
Difference from the station mean
1955
11.6 C
-0.71 C
1956
12.1 C
-0.15 C
1957
12.3 C
+0.01 C
1958
14.1 C
+1.83 C
1959
12.2 C
-0.13 C
1960
12.0 C
-0.26 C
1961
13.1 C
+0.82 C
1962
11.8 C
-0.51 C
1963
11.9 C
-0.41 C
1964
11.9 C
-0.44 C
1965
12.9 C
+0.64 C
1966
13.1 C
+0.78 C
1967
13.8 C
+1.55 C
1968
12.8 C
+0.46 C
1969
12.0 C
-0.28 C
1970
12.1 C
-0.20 C
1971
12.6 C
+0.28 C
1972
11.8 C
-0.49 C
1973
12.6 C
+0.27 C
1974
12.4 C
+0.15 C
1975
11.5 C
-0.84 C
1976
11.7 C
-0.60 C
1977
12.1 C
-0.23 C
1979
11.8 C
-0.46 C
1983
12.4 C
+0.13 C
1984
11.7 C
-0.61 C
1985
10.7 C
-1.64 C
1986
12.5 C
+0.22 C
1987
12.9 C
+0.61 C
1988
12.6 C
+0.27 C
1989
11.9 C
-0.43 C
1990
12.7 C
+0.40 C
1991
12.2 C
-0.11 C
1992
13.0 C
+0.69 C
1993
10.5 C
-1.78 C
1994
12.8 C
+0.49 C
1995
12.3 C
-0.04 C
1996
11.3 C
-1.04 C
1997
12.2 C
-0.13 C
1998
13.1 C
+0.85 C
1999
12.5 C
+0.20 C
2000
11.9 C
-0.39 C
2001
12.4 C
+0.12 C
2002
12.2 C
-0.05 C
2003
13.2 C
+0.93 C
2004
12.7 C
+0.45 C
The fitted trend in annual mean temperature here over 1955 to 2004 is -0.02 C (-0.16 to 0.12) per decade. The interval includes zero, so the trend is not clearly different from zero. In Fahrenheit: -0.04 F (-0.29 to 0.21) per decade. The slope is a straight line fitted to 46 complete years; the brackets give its 95 percent interval.
Fitted temperature trends per decade at McNary Dam
Measure
Per decade (C)
Per decade (F)
Period
Complete years
Reading
Annual mean temperature
-0.02 C (-0.16 to 0.12) per decade
-0.04 F (-0.29 to 0.21) per decade
1955 to 2004
46
Not clearly different from zero
Mean daily maximum
-0.1 C (-0.2 to 0.1) per decade
-0.1 F (-0.4 to 0.1) per decade
1955 to 2004
46
Not clearly different from zero
Mean daily minimum
0.02 C (-0.11 to 0.16) per decade
0.04 F (-0.20 to 0.28) per decade
1955 to 2004
46
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
1954 to 2007
Yearly extremes at McNary Dam: the record and the median year
Measure
Record
Year of the record
Median year
Years with a value
Hottest day (TXx)
43.9 C (111.0 F)
1961
39.4 C (102.9 F)
54
Coldest night (TNn)
-22.8 C (-9.0 F)
1983
-13.0 C (8.5 F)
54
Wettest day (Rx1day)
53.8 mm (2.1 in)
1957
15.2 mm (0.6 in)
54
Wettest five days (Rx5day)
80.7 mm (3.2 in)
1957
24.9 mm (1.0 in)
54
Longest dry spell (CDD)
111 days
1974
54 days
54
Hottest day (TXx)
The hottest day of the year at McNary Dam, 1954 to 2007. The record is 43.9 C (111.0 F) in 1961, marked on the chart; the median year is 39.4 C (102.9 F).
Hottest day (TXx) at McNary Dam by year
Year
Hottest day (TXx)
1954
20.6 C (69.1 F)
1955
40.0 C (104.0 F)
1956
41.1 C (106.0 F)
1957
37.8 C (100.0 F)
1958
42.8 C (109.0 F)
1959
41.7 C (107.1 F)
1960
43.3 C (109.9 F)
1961
43.9 C (111.0 F)
1962
40.0 C (104.0 F)
1963
38.3 C (100.9 F)
1964
40.6 C (105.1 F)
1965
40.6 C (105.1 F)
1966
37.2 C (99.0 F)
1967
41.1 C (106.0 F)
1968
41.1 C (106.0 F)
1969
37.2 C (99.0 F)
1970
38.9 C (102.0 F)
1971
41.7 C (107.1 F)
1972
40.0 C (104.0 F)
1973
38.9 C (102.0 F)
1974
38.9 C (102.0 F)
1975
38.9 C (102.0 F)
1976
37.8 C (100.0 F)
1977
39.4 C (102.9 F)
1978
39.4 C (102.9 F)
1979
41.1 C (106.0 F)
1980
37.8 C (100.0 F)
1981
26.7 C (80.1 F)
1982
40.0 C (104.0 F)
1983
40.0 C (104.0 F)
1984
41.1 C (106.0 F)
1985
39.4 C (102.9 F)
1986
38.3 C (100.9 F)
1987
40.0 C (104.0 F)
1988
38.9 C (102.0 F)
1989
37.2 C (99.0 F)
1990
40.6 C (105.1 F)
1991
37.8 C (100.0 F)
1992
41.1 C (106.0 F)
1993
36.7 C (98.1 F)
1994
41.7 C (107.1 F)
1995
37.2 C (99.0 F)
1996
38.3 C (100.9 F)
1997
37.2 C (99.0 F)
1998
40.6 C (105.1 F)
1999
37.2 C (99.0 F)
2000
37.8 C (100.0 F)
2001
38.9 C (102.0 F)
2002
38.9 C (102.0 F)
2003
40.6 C (105.1 F)
2004
40.0 C (104.0 F)
2005
34.4 C (93.9 F)
2006
42.2 C (108.0 F)
2007
40.0 C (104.0 F)
Coldest night (TNn)
The coldest night of the year at McNary Dam, 1954 to 2007. The record is -22.8 C (-9.0 F) in 1983, marked on the chart; the median year is -13.0 C (8.5 F).
Coldest night (TNn) at McNary Dam by year
Year
Coldest night (TNn)
1954
-5.0 C (23.0 F)
1955
-18.9 C (-2.0 F)
1956
-17.8 C (0.0 F)
1957
-22.2 C (-8.0 F)
1958
-7.8 C (18.0 F)
1959
-16.7 C (1.9 F)
1960
-11.7 C (10.9 F)
1961
-11.7 C (10.9 F)
1962
-17.8 C (0.0 F)
1963
-17.8 C (0.0 F)
1964
-19.4 C (-2.9 F)
1965
-7.2 C (19.0 F)
1966
-4.4 C (24.1 F)
1967
-11.1 C (12.0 F)
1968
-20.6 C (-5.1 F)
1969
-18.3 C (-0.9 F)
1970
-8.3 C (17.1 F)
1971
-9.4 C (15.1 F)
1972
-20.0 C (-4.0 F)
1973
-17.2 C (1.0 F)
1974
-18.9 C (-2.0 F)
1975
-8.9 C (16.0 F)
1976
-10.6 C (12.9 F)
1977
-13.3 C (8.1 F)
1978
-17.8 C (0.0 F)
1979
-21.7 C (-7.1 F)
1980
-16.7 C (1.9 F)
1981
-9.4 C (15.1 F)
1982
-14.4 C (6.1 F)
1983
-22.8 C (-9.0 F)
1984
-16.1 C (3.0 F)
1985
-19.4 C (-2.9 F)
1986
-6.1 C (21.0 F)
1987
-7.8 C (18.0 F)
1988
-10.6 C (12.9 F)
1989
-21.1 C (-6.0 F)
1990
-21.7 C (-7.1 F)
1991
-8.3 C (17.1 F)
1992
-8.3 C (17.1 F)
1993
-15.6 C (3.9 F)
1994
-12.8 C (9.0 F)
1995
-11.1 C (12.0 F)
1996
-21.7 C (-7.1 F)
1997
-9.4 C (15.1 F)
1998
-15.0 C (5.0 F)
1999
-3.9 C (25.0 F)
2000
-7.2 C (19.0 F)
2001
-4.4 C (24.1 F)
2002
-7.8 C (18.0 F)
2003
-9.4 C (15.1 F)
2004
-18.9 C (-2.0 F)
2005
-9.4 C (15.1 F)
2006
-10.6 C (12.9 F)
2007
-13.3 C (8.1 F)
Wettest day (Rx1day)
The wettest day of the year at McNary Dam, 1954 to 2007. The record is 53.8 mm (2.1 in) in 1957, marked on the chart; the median year is 15.2 mm (0.6 in).
Wettest day (Rx1day) at McNary Dam by year
Year
Wettest day (Rx1day)
1954
9.9 mm (0.39 in)
1955
9.9 mm (0.39 in)
1956
18.0 mm (0.7 in)
1957
53.8 mm (2.1 in)
1958
16.0 mm (0.6 in)
1959
13.5 mm (0.5 in)
1960
8.9 mm (0.35 in)
1961
12.7 mm (0.5 in)
1962
17.3 mm (0.7 in)
1963
11.4 mm (0.4 in)
1964
25.9 mm (1.0 in)
1965
12.7 mm (0.5 in)
1966
17.8 mm (0.7 in)
1967
5.6 mm (0.22 in)
1968
18.5 mm (0.7 in)
1969
15.7 mm (0.6 in)
1970
16.5 mm (0.6 in)
1971
17.8 mm (0.7 in)
1972
11.2 mm (0.4 in)
1973
20.1 mm (0.8 in)
1974
11.4 mm (0.4 in)
1975
23.4 mm (0.9 in)
1976
9.1 mm (0.36 in)
1977
20.1 mm (0.8 in)
1978
17.8 mm (0.7 in)
1979
22.4 mm (0.9 in)
1980
13.7 mm (0.5 in)
1981
15.7 mm (0.6 in)
1982
25.4 mm (1.0 in)
1983
15.2 mm (0.6 in)
1984
13.5 mm (0.5 in)
1985
10.2 mm (0.4 in)
1986
15.2 mm (0.6 in)
1987
15.7 mm (0.6 in)
1988
28.7 mm (1.1 in)
1989
15.7 mm (0.6 in)
1990
15.2 mm (0.6 in)
1991
15.2 mm (0.6 in)
1992
14.5 mm (0.6 in)
1993
8.1 mm (0.32 in)
1994
25.7 mm (1.0 in)
1995
14.0 mm (0.6 in)
1996
42.7 mm (1.7 in)
1997
17.8 mm (0.7 in)
1998
13.5 mm (0.5 in)
1999
11.4 mm (0.4 in)
2000
16.0 mm (0.6 in)
2001
14.0 mm (0.6 in)
2002
12.7 mm (0.5 in)
2003
13.0 mm (0.5 in)
2004
12.7 mm (0.5 in)
2005
9.9 mm (0.39 in)
2006
12.7 mm (0.5 in)
2007
51.6 mm (2.0 in)
Wettest five days (Rx5day)
The wettest five days of the year at McNary Dam, 1954 to 2007. The record is 80.7 mm (3.2 in) in 1957, marked on the chart; the median year is 24.9 mm (1.0 in).
Wettest five days (Rx5day) at McNary Dam by year
Year
Wettest five days (Rx5day)
1954
17.3 mm (0.7 in)
1955
22.2 mm (0.9 in)
1956
30.9 mm (1.2 in)
1957
80.7 mm (3.2 in)
1958
26.4 mm (1.0 in)
1959
26.2 mm (1.0 in)
1960
14.7 mm (0.6 in)
1961
27.2 mm (1.1 in)
1962
33.6 mm (1.3 in)
1963
20.3 mm (0.8 in)
1964
64.4 mm (2.5 in)
1965
19.3 mm (0.8 in)
1966
29.0 mm (1.1 in)
1967
13.8 mm (0.5 in)
1968
28.7 mm (1.1 in)
1969
19.6 mm (0.8 in)
1970
36.5 mm (1.4 in)
1971
33.1 mm (1.3 in)
1972
18.3 mm (0.7 in)
1973
29.7 mm (1.2 in)
1974
29.4 mm (1.2 in)
1975
39.6 mm (1.6 in)
1976
16.1 mm (0.6 in)
1977
28.6 mm (1.1 in)
1978
24.0 mm (0.9 in)
1979
25.0 mm (1.0 in)
1980
20.8 mm (0.8 in)
1981
24.2 mm (1.0 in)
1982
29.5 mm (1.2 in)
1983
28.6 mm (1.1 in)
1984
18.5 mm (0.7 in)
1985
19.1 mm (0.8 in)
1986
18.2 mm (0.7 in)
1987
24.8 mm (1.0 in)
1988
40.1 mm (1.6 in)
1989
24.8 mm (1.0 in)
1990
24.1 mm (0.9 in)
1991
19.5 mm (0.8 in)
1992
23.2 mm (0.9 in)
1993
16.8 mm (0.7 in)
1994
37.2 mm (1.5 in)
1995
18.4 mm (0.7 in)
1996
55.9 mm (2.2 in)
1997
29.3 mm (1.2 in)
1998
31.8 mm (1.3 in)
1999
23.7 mm (0.9 in)
2000
19.3 mm (0.8 in)
2001
17.3 mm (0.7 in)
2002
28.0 mm (1.1 in)
2003
27.0 mm (1.1 in)
2004
22.9 mm (0.9 in)
2005
24.4 mm (1.0 in)
2006
31.5 mm (1.2 in)
2007
60.5 mm (2.4 in)
Longest dry spell (CDD)
The longest dry spell of the year at McNary Dam, 1954 to 2007. The record is 111 days in 1974, marked on the chart; the median year is 54 days.
Longest dry spell (CDD) at McNary Dam by year
Year
Longest dry spell (CDD)
1954
21 days
1955
48 days
1956
38 days
1957
65 days
1958
81 days
1959
72 days
1960
47 days
1961
64 days
1962
54 days
1963
48 days
1964
66 days
1965
70 days
1966
72 days
1967
80 days
1968
56 days
1969
81 days
1970
61 days
1971
54 days
1972
36 days
1973
57 days
1974
111 days
1975
38 days
1976
60 days
1977
51 days
1978
40 days
1979
44 days
1980
53 days
1981
74 days
1982
25 days
1983
40 days
1984
38 days
1985
52 days
1986
55 days
1987
78 days
1988
65 days
1989
59 days
1990
52 days
1991
76 days
1992
41 days
1993
56 days
1994
64 days
1995
58 days
1996
45 days
1997
46 days
1998
48 days
1999
66 days
2000
82 days
2001
47 days
2002
43 days
2003
66 days
2004
54 days
2005
32 days
2006
40 days
2007
51 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
46 years with a frost
Across 46 years with a frost, the median last spring frost at McNary Dam falls on 29 March and the median first autumn frost on 3 November, which leaves a median of 223 days between them.
Fitted over all years, the growing season changes by +4.5 days per decade at this station.
Frost dates and growing season at McNary Dam
Measure
Median, all years
Earliest period
Recent period (1971 to 2004)
Recent against earliest
Fitted trend
Last spring frost
29 March
n/a
26 March
n/a
-3.5 days per decade
First autumn frost
3 November
n/a
4 November
n/a
+1.0 days per decade
Growing days
223 days
n/a
228 days
n/a
+4.5 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
51 years, 1955 to 2006
A day with at least 14.7 mm (0.6 in) of rain is expected about once in 2 years. A day with at least 47.7 mm (1.9 in) of rain is expected about once in 100 years.
Rainfall return levels at McNary 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
14.7 mm (0.6 in)
5 years
20.4 mm (0.8 in)
10 years
25.2 mm (1.0 in)
25 years
32.7 mm (1.3 in)
50 years
39.6 mm (1.6 in)
100 years
47.7 mm (1.9 in)
Longer than the 51 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, 51 years of values from 1955 to 2006.
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: 53.8 mm (2.1 in) in 1957; 42.7 mm (1.7 in) in 1996; 28.7 mm (1.1 in) in 1988.
Station Changes
No change in the annual mean temperature of this station was found against its neighbours.
Download the Data
Data for McNary Dam standing records by year: CSV or JSON. Field meanings are on the data page.
Data for McNary 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 2026-10-14 (14 October 2026). Records are computed by this site and are not official.