Record envelope, standing records and threshold days for Prosser (USC00456763), Washington, United States, with 52 years of record.
Key Facts for Prosser
Prosser (USC00456763) is a weather station in Washington, United States at 46.20 latitude and -119.77 longitude, 207 m (679 ft) above sea level.
The station reports from 1912 to 1963, 52 years of record.
1,464 records set at Prosser still stand.
Records are tracked for tmax, tmin, prcp, snow: an element needs 30 years of data to be eligible.
Prosser set a daily record low maximum temperature of -10.0 C (14.0 F) on 11 January 1963.
About the Station
Location: Washington, United States, 46.20 latitude, -119.77 longitude.
Elevation: 207 m (679 ft).
Period of record: 1912 to 1963, 52 years.
Eligible elements: tmax, tmin, prcp, snow.
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 Prosser. 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 Prosser, 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)
-28.9 C (-20.0 F)
n/a
n/a
Feb
21.1 C (70.0 F)
-30.0 C (-22.0 F)
n/a
n/a
Mar
28.9 C (84.0 F)
-12.8 C (9.0 F)
n/a
n/a
Apr
34.4 C (93.9 F)
-8.9 C (16.0 F)
n/a
n/a
May
37.8 C (100.0 F)
-2.8 C (27.0 F)
n/a
n/a
Jun
40.6 C (105.1 F)
0.0 C (32.0 F)
n/a
n/a
Jul
43.9 C (111.0 F)
0.0 C (32.0 F)
n/a
n/a
Aug
41.1 C (106.0 F)
2.8 C (37.0 F)
n/a
n/a
Sep
37.8 C (100.0 F)
-6.7 C (19.9 F)
n/a
n/a
Oct
31.7 C (89.1 F)
-11.1 C (12.0 F)
n/a
n/a
Nov
23.9 C (75.0 F)
-17.8 C (0.0 F)
n/a
n/a
Dec
20.0 C (68.0 F)
-27.2 C (-17.0 F)
n/a
n/a
Which Years Hold Standing Records
1,464 standing records
Year with most
1,464 records at Prosser still stand. 1916 holds the most, with 67.
Standing records at Prosser by the year they were set
Year set
Standing records
1912
24
1913
35
1914
46
1915
26
1916
67
1917
50
1918
35
1919
48
1920
22
1921
24
1922
35
1923
17
1924
29
1925
35
1926
30
1927
20
1928
30
1929
30
1930
30
1931
30
1932
35
1933
40
1934
44
1935
24
1936
41
1937
32
1938
17
1939
20
1940
26
1941
24
1942
24
1943
18
1944
18
1945
22
1946
14
1947
20
1948
26
1949
30
1950
35
1951
20
1952
18
1953
18
1954
19
1955
33
1956
23
1957
28
1958
23
1959
22
1960
27
1961
31
1962
27
1963
2
All-Time Record Progression
2 new records
2 all-time records were set at Prosser between 1 February 1950 and 5 June 1957. Each dot is a new record.
When Prosser set new all-time records
Date
Kind
Detail
1950-02-01
Record low minimum temperature
Record low minimum temperature -30.0 C (-22.0 F)
1957-06-05
Record daily precipitation
Record daily precipitation 44.7 mm (1.8 in)
Wettest Day of Each Month
Jun: 44.7 mm (1.8 in)
The wettest day on record for each calendar month at Prosser. The most was 44.7 mm (1.8 in) on 5 June 1957.
Record daily precipitation for each month at Prosser
Month
Record daily precipitation (mm)
Date
Jan
29.2 mm (1.1 in)
16 January 1946
Feb
19.3 mm (0.8 in)
6 February 1943
Mar
14.2 mm (0.6 in)
26 March 1928
Apr
16.5 mm (0.6 in)
29 April 1961
May
25.1 mm (1.0 in)
22 May 1914
Jun
44.7 mm (1.8 in)
5 June 1957
Jul
14.2 mm (0.6 in)
29 July 1915
Aug
19.1 mm (0.8 in)
31 August 1946
Sep
20.3 mm (0.8 in)
25 September 1925
Oct
29.2 mm (1.1 in)
2 October 1957
Nov
32.0 mm (1.3 in)
20 November 1921
Dec
22.4 mm (0.9 in)
6 December 1948
Period of Record Coverage
1912 to 1963
Complete yearUnder 90 percent of days
52 years of record at Prosser, 1912 to 1963. 7 years have data for under 90 percent of days and are left out of rankings: 1912, 1923, 1924, 1927, 1946, 1948, 1963.
Cooler than the station meanWarmer than the station mean
One stripe for each of 42 complete years at Prosser, 1913 to 1962. Blue stripes are years cooler than the station's own mean of 11.2 C (52.2 F); red stripes are warmer. The coolest year was 1916, at 8.9 C (48.1 F), and the warmest was 1934, at 13.6 C (56.6 F). The strongest colour marks a difference of 2.4 C (4.3 F).
Annual mean temperature at Prosser as warming stripes, 1913 to 1962
Year
Annual mean temperature
Difference from the station mean
1913
10.8 C
-0.48 C
1914
11.5 C
+0.24 C
1915
11.4 C
+0.16 C
1916
8.9 C
-2.31 C
1917
10.8 C
-0.46 C
1918
11.2 C
-0.02 C
1919
10.1 C
-1.18 C
1920
10.4 C
-0.89 C
1921
11.0 C
-0.20 C
1922
9.8 C
-1.43 C
1925
12.6 C
+1.35 C
1926
12.2 C
+0.94 C
1928
11.6 C
+0.31 C
1929
9.8 C
-1.46 C
1931
11.6 C
+0.31 C
1932
11.3 C
+0.07 C
1933
11.5 C
+0.30 C
1934
13.6 C
+2.40 C
1936
11.0 C
-0.22 C
1937
10.8 C
-0.40 C
1938
11.9 C
+0.68 C
1939
12.2 C
+0.96 C
1941
12.3 C
+1.02 C
1942
10.8 C
-0.42 C
1943
10.4 C
-0.88 C
1944
10.4 C
-0.82 C
1945
11.3 C
+0.01 C
1947
11.9 C
+0.65 C
1949
10.6 C
-0.63 C
1950
10.5 C
-0.74 C
1951
11.1 C
-0.10 C
1952
11.3 C
+0.03 C
1953
12.5 C
+1.24 C
1954
11.2 C
-0.09 C
1955
10.5 C
-0.74 C
1956
11.2 C
-0.04 C
1957
11.0 C
-0.20 C
1958
13.1 C
+1.83 C
1959
11.3 C
+0.05 C
1960
11.0 C
-0.21 C
1961
12.3 C
+1.06 C
1962
11.7 C
+0.46 C
The fitted trend in annual mean temperature here over 1913 to 1962 is 0.15 C (-0.03 to 0.34) per decade. The interval includes zero, so the trend is not clearly different from zero. In Fahrenheit: 0.3 F (-0.1 to 0.6) per decade. The slope is a straight line fitted to 42 complete years; the brackets give its 95 percent interval.
Fitted temperature trends per decade at Prosser
Measure
Per decade (C)
Per decade (F)
Period
Complete years
Reading
Annual mean temperature
0.15 C (-0.03 to 0.34) per decade
0.3 F (-0.1 to 0.6) per decade
1913 to 1962
42
Not clearly different from zero
Mean daily maximum
-0.1 C (-0.3 to 0.1) per decade
-0.1 F (-0.5 to 0.3) per decade
1913 to 1962
42
Not clearly different from zero
Mean daily minimum
0.4 C (0.2 to 0.6) per decade
0.7 F (0.3 to 1.0) per decade
1913 to 1962
42
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
1912 to 1963
Yearly extremes at Prosser: 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)
1928
39.4 C (102.9 F)
52
Coldest night (TNn)
-30.0 C (-22.0 F)
1950
-16.7 C (1.9 F)
52
Wettest day (Rx1day)
44.7 mm (1.8 in)
1957
17.1 mm (0.7 in)
50
Wettest five days (Rx5day)
52.0 mm (2.0 in)
1921
28.4 mm (1.1 in)
49
Longest dry spell (CDD)
118 days
1932
51 days
50
Hottest day (TXx)
The hottest day of the year at Prosser, 1912 to 1963. The record is 43.9 C (111.0 F) in 1928, marked on the chart; the median year is 39.4 C (102.9 F).
Hottest day (TXx) at Prosser by year
Year
Hottest day (TXx)
1912
40.6 C (105.1 F)
1913
42.8 C (109.0 F)
1914
41.1 C (106.0 F)
1915
41.1 C (106.0 F)
1916
37.8 C (100.0 F)
1917
39.4 C (102.9 F)
1918
40.0 C (104.0 F)
1919
39.4 C (102.9 F)
1920
38.9 C (102.0 F)
1921
36.7 C (98.1 F)
1922
41.1 C (106.0 F)
1923
38.9 C (102.0 F)
1924
40.6 C (105.1 F)
1925
40.0 C (104.0 F)
1926
41.1 C (106.0 F)
1927
39.4 C (102.9 F)
1928
43.9 C (111.0 F)
1929
41.1 C (106.0 F)
1930
40.6 C (105.1 F)
1931
39.4 C (102.9 F)
1932
37.2 C (99.0 F)
1933
39.4 C (102.9 F)
1934
40.6 C (105.1 F)
1935
40.6 C (105.1 F)
1936
38.9 C (102.0 F)
1937
38.3 C (100.9 F)
1938
39.4 C (102.9 F)
1939
42.2 C (108.0 F)
1940
38.3 C (100.9 F)
1941
40.6 C (105.1 F)
1942
39.4 C (102.9 F)
1943
37.2 C (99.0 F)
1944
40.0 C (104.0 F)
1945
37.8 C (100.0 F)
1946
38.3 C (100.9 F)
1947
36.7 C (98.1 F)
1948
38.9 C (102.0 F)
1949
39.4 C (102.9 F)
1950
37.8 C (100.0 F)
1951
37.8 C (100.0 F)
1952
38.9 C (102.0 F)
1953
37.8 C (100.0 F)
1954
36.1 C (97.0 F)
1955
38.9 C (102.0 F)
1956
38.9 C (102.0 F)
1957
36.7 C (98.1 F)
1958
38.9 C (102.0 F)
1959
38.3 C (100.9 F)
1960
40.0 C (104.0 F)
1961
40.0 C (104.0 F)
1962
37.8 C (100.0 F)
1963
14.4 C (57.9 F)
Coldest night (TNn)
The coldest night of the year at Prosser, 1912 to 1963. The record is -30.0 C (-22.0 F) in 1950, marked on the chart; the median year is -16.7 C (1.9 F).
Coldest night (TNn) at Prosser by year
Year
Coldest night (TNn)
1912
-8.9 C (16.0 F)
1913
-16.1 C (3.0 F)
1914
-17.8 C (0.0 F)
1915
-12.8 C (9.0 F)
1916
-26.1 C (-15.0 F)
1917
-16.7 C (1.9 F)
1918
-14.4 C (6.1 F)
1919
-27.2 C (-17.0 F)
1920
-12.8 C (9.0 F)
1921
-16.7 C (1.9 F)
1922
-24.4 C (-11.9 F)
1923
-16.7 C (1.9 F)
1924
-22.8 C (-9.0 F)
1925
-8.9 C (16.0 F)
1926
-16.7 C (1.9 F)
1927
-27.2 C (-17.0 F)
1928
-13.9 C (7.0 F)
1929
-27.2 C (-17.0 F)
1930
-25.0 C (-13.0 F)
1931
-16.7 C (1.9 F)
1932
-23.3 C (-9.9 F)
1933
-21.7 C (-7.1 F)
1934
-5.6 C (21.9 F)
1935
-20.0 C (-4.0 F)
1936
-23.9 C (-11.0 F)
1937
-27.2 C (-17.0 F)
1938
-13.3 C (8.1 F)
1939
-12.2 C (10.0 F)
1940
-13.3 C (8.1 F)
1941
-12.2 C (10.0 F)
1942
-20.0 C (-4.0 F)
1943
-25.0 C (-13.0 F)
1944
-14.4 C (6.1 F)
1945
-12.2 C (10.0 F)
1946
-12.2 C (10.0 F)
1947
-17.8 C (0.0 F)
1948
-18.3 C (-0.9 F)
1949
-23.3 C (-9.9 F)
1950
-30.0 C (-22.0 F)
1951
-16.1 C (3.0 F)
1952
-13.9 C (7.0 F)
1953
-5.6 C (21.9 F)
1954
-26.1 C (-15.0 F)
1955
-17.8 C (0.0 F)
1956
-24.4 C (-11.9 F)
1957
-28.9 C (-20.0 F)
1958
-12.2 C (10.0 F)
1959
-17.8 C (0.0 F)
1960
-15.6 C (3.9 F)
1961
-13.3 C (8.1 F)
1962
-14.4 C (6.1 F)
1963
-17.8 C (0.0 F)
Wettest day (Rx1day)
The wettest day of the year at Prosser, 1912 to 1963. The record is 44.7 mm (1.8 in) in 1957, marked on the chart; the median year is 17.1 mm (0.7 in).
Wettest day (Rx1day) at Prosser by year
Year
Wettest day (Rx1day)
1912
n/a
1913
15.2 mm (0.6 in)
1914
25.1 mm (1.0 in)
1915
17.3 mm (0.7 in)
1916
14.0 mm (0.6 in)
1917
18.3 mm (0.7 in)
1918
14.0 mm (0.6 in)
1919
16.8 mm (0.7 in)
1920
15.7 mm (0.6 in)
1921
32.0 mm (1.3 in)
1922
12.7 mm (0.5 in)
1923
11.4 mm (0.4 in)
1924
18.0 mm (0.7 in)
1925
20.3 mm (0.8 in)
1926
17.3 mm (0.7 in)
1927
15.7 mm (0.6 in)
1928
14.2 mm (0.6 in)
1929
11.2 mm (0.4 in)
1930
8.1 mm (0.32 in)
1931
16.5 mm (0.6 in)
1932
14.0 mm (0.6 in)
1933
18.8 mm (0.7 in)
1934
16.5 mm (0.6 in)
1935
9.7 mm (0.38 in)
1936
21.6 mm (0.9 in)
1937
16.5 mm (0.6 in)
1938
20.6 mm (0.8 in)
1939
25.7 mm (1.0 in)
1940
16.8 mm (0.7 in)
1941
17.8 mm (0.7 in)
1942
19.1 mm (0.8 in)
1943
19.3 mm (0.8 in)
1944
19.3 mm (0.8 in)
1945
15.7 mm (0.6 in)
1946
29.2 mm (1.1 in)
1947
24.4 mm (1.0 in)
1948
22.4 mm (0.9 in)
1949
14.2 mm (0.6 in)
1950
30.2 mm (1.2 in)
1951
16.3 mm (0.6 in)
1952
8.6 mm (0.34 in)
1953
14.0 mm (0.6 in)
1954
16.3 mm (0.6 in)
1955
18.0 mm (0.7 in)
1956
23.9 mm (0.9 in)
1957
44.7 mm (1.8 in)
1958
17.3 mm (0.7 in)
1959
22.6 mm (0.9 in)
1960
14.0 mm (0.6 in)
1961
18.5 mm (0.7 in)
1962
16.8 mm (0.7 in)
1963
n/a
Wettest five days (Rx5day)
The wettest five days of the year at Prosser, 1912 to 1963. The record is 52.0 mm (2.0 in) in 1921, marked on the chart; the median year is 28.4 mm (1.1 in).
Wettest five days (Rx5day) at Prosser by year
Year
Wettest five days (Rx5day)
1912
n/a
1913
23.1 mm (0.9 in)
1914
25.4 mm (1.0 in)
1915
24.9 mm (1.0 in)
1916
31.8 mm (1.3 in)
1917
22.7 mm (0.9 in)
1918
16.5 mm (0.6 in)
1919
23.7 mm (0.9 in)
1920
29.2 mm (1.1 in)
1921
52.0 mm (2.0 in)
1922
20.2 mm (0.8 in)
1923
20.8 mm (0.8 in)
1924
32.0 mm (1.3 in)
1925
24.2 mm (1.0 in)
1926
36.7 mm (1.4 in)
1927
21.1 mm (0.8 in)
1928
n/a
1929
8.4 mm (0.33 in)
1930
17.3 mm (0.7 in)
1931
22.8 mm (0.9 in)
1932
19.9 mm (0.8 in)
1933
15.0 mm (0.6 in)
1934
28.9 mm (1.1 in)
1935
10.7 mm (0.4 in)
1936
21.6 mm (0.9 in)
1937
31.5 mm (1.2 in)
1938
41.7 mm (1.6 in)
1939
15.8 mm (0.6 in)
1940
33.8 mm (1.3 in)
1941
25.2 mm (1.0 in)
1942
30.1 mm (1.2 in)
1943
29.2 mm (1.1 in)
1944
30.2 mm (1.2 in)
1945
30.2 mm (1.2 in)
1946
29.2 mm (1.1 in)
1947
34.1 mm (1.3 in)
1948
39.7 mm (1.6 in)
1949
23.7 mm (0.9 in)
1950
32.5 mm (1.3 in)
1951
40.7 mm (1.6 in)
1952
17.5 mm (0.7 in)
1953
30.3 mm (1.2 in)
1954
24.5 mm (1.0 in)
1955
28.2 mm (1.1 in)
1956
32.8 mm (1.3 in)
1957
49.3 mm (1.9 in)
1958
28.4 mm (1.1 in)
1959
37.1 mm (1.5 in)
1960
16.3 mm (0.6 in)
1961
37.1 mm (1.5 in)
1962
35.9 mm (1.4 in)
1963
n/a
Longest dry spell (CDD)
The longest dry spell of the year at Prosser, 1912 to 1963. The record is 118 days in 1932, marked on the chart; the median year is 51 days.
Longest dry spell (CDD) at Prosser by year
Year
Longest dry spell (CDD)
1912
n/a
1913
34 days
1914
56 days
1915
71 days
1916
54 days
1917
69 days
1918
45 days
1919
95 days
1920
70 days
1921
80 days
1922
61 days
1923
42 days
1924
78 days
1925
74 days
1926
78 days
1927
38 days
1928
2 days
1929
13 days
1930
79 days
1931
31 days
1932
118 days
1933
28 days
1934
56 days
1935
31 days
1936
30 days
1937
35 days
1938
18 days
1939
2 days
1940
19 days
1941
38 days
1942
57 days
1943
66 days
1944
76 days
1945
43 days
1946
48 days
1947
32 days
1948
24 days
1949
90 days
1950
103 days
1951
49 days
1952
67 days
1953
56 days
1954
67 days
1955
49 days
1956
42 days
1957
65 days
1958
50 days
1959
60 days
1960
49 days
1961
51 days
1962
51 days
1963
n/a
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
42 years with a frost
Across 42 years with a frost, the median last spring frost at Prosser falls on 2 May and the median first autumn frost on 7 October, which leaves a median of 155 days between them.
Fitted over all years, the growing season changes by +10.9 days per decade at this station.
Frost dates and growing season at Prosser
Measure
Median, all years
Earliest period
Recent period (1928 to 1962)
Recent against earliest
Fitted trend
Last spring frost
2 May
n/a
30 April
n/a
-3.4 days per decade
First autumn frost
7 October
n/a
10 October
n/a
+7.5 days per decade
Growing days
155 days
n/a
163 days
n/a
+10.9 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
35 years, 1914 to 1962
A day with at least 17.1 mm (0.7 in) of rain is expected about once in 2 years. A day with at least 46.7 mm (1.8 in) of rain is expected about once in 100 years.
Rainfall return levels at Prosser: the daily rain expected about once in a given number of years
Expected about once in
A day with at least
Note
2 years
17.1 mm (0.7 in)
5 years
22.4 mm (0.9 in)
10 years
26.8 mm (1.1 in)
25 years
33.6 mm (1.3 in)
50 years
39.6 mm (1.6 in)
Longer than the 35 years of record
100 years
46.7 mm (1.8 in)
Longer than the 35 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, 35 years of values from 1914 to 1962.
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: 44.7 mm (1.8 in) in 1957; 32.0 mm (1.3 in) in 1921; 30.2 mm (1.2 in) in 1950.
Station Changes
1 suspected
One change was suspected in the annual mean temperature of Prosser, at 1953. Each is measured against neighbouring stations.
Relative to 5 neighbouring stations, the station's annual mean temperature from 1953 ran 0.3 C (0.6 F) higher than in the years before (likely change).
Suspected changes in the annual mean temperature at Prosser, against neighbouring stations
Year
Shift (C)
Shift (F)
Strength
Neighbours
1953
+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 Prosser standing records by year: CSV or JSON. Field meanings are on the data page.
Data for Prosser 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.