Record envelope, standing records and threshold days for Arizona Falls 1 WNW (USC00021161), Arizona, United States, with 44 years of record.
Key Facts for Arizona Falls 1 WNW
Arizona Falls 1 WNW (USC00021161) is a weather station in Arizona, United States at 33.48 latitude and -111.97 longitude, 381 m (1,250 ft) above sea level.
The station reports from 1920 to 1963, 44 years of record.
1,464 records set at Arizona Falls 1 WNW still stand.
Records are tracked for tmax, tmin, prcp: an element needs 30 years of data to be eligible.
Arizona Falls 1 WNW set a daily record low minimum temperature of 4.4 C (39.9 F) on 27 April 1963.
About the Station
Location: Arizona, United States, 33.48 latitude, -111.97 longitude.
Elevation: 381 m (1,250 ft).
Period of record: 1920 to 1963, 44 years.
Eligible elements: tmax, tmin, prcp.
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 Arizona Falls 1 WNW. 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 Arizona Falls 1 WNW, with 2026 drawn through them
Month
Highest record high
Lowest record low
2026 highest maximum
2026 lowest minimum
Jan
30.6 C (87.1 F)
-9.4 C (15.1 F)
n/a
n/a
Feb
33.3 C (91.9 F)
-6.7 C (19.9 F)
n/a
n/a
Mar
35.6 C (96.1 F)
-3.3 C (26.1 F)
n/a
n/a
Apr
40.6 C (105.1 F)
0.0 C (32.0 F)
n/a
n/a
May
45.6 C (114.1 F)
3.9 C (39.0 F)
n/a
n/a
Jun
47.8 C (118.0 F)
4.4 C (39.9 F)
n/a
n/a
Jul
48.3 C (118.9 F)
13.9 C (57.0 F)
n/a
n/a
Aug
46.1 C (115.0 F)
14.4 C (57.9 F)
n/a
n/a
Sep
46.1 C (115.0 F)
7.8 C (46.0 F)
n/a
n/a
Oct
41.7 C (107.1 F)
0.0 C (32.0 F)
n/a
n/a
Nov
35.6 C (96.1 F)
-5.6 C (21.9 F)
n/a
n/a
Dec
31.7 C (89.1 F)
-6.1 C (21.0 F)
n/a
n/a
Which Years Hold Standing Records
1,464 standing records
Year with most
1,464 records at Arizona Falls 1 WNW still stand. 1921 holds the most, with 70.
Standing records at Arizona Falls 1 WNW by the year they were set
Year set
Standing records
1920
1
1921
70
1922
8
1923
21
1924
30
1925
38
1926
33
1927
66
1928
31
1929
28
1930
42
1931
35
1932
19
1933
37
1934
52
1935
41
1936
31
1937
28
1938
37
1939
38
1940
40
1941
31
1942
23
1943
31
1944
38
1945
34
1946
27
1947
50
1948
29
1949
52
1950
45
1951
27
1952
31
1953
41
1954
28
1955
37
1956
26
1957
33
1958
32
1959
21
1960
36
1961
28
1962
24
1963
14
All-Time Record Progression
3 new records
3 all-time records were set at Arizona Falls 1 WNW between 24 June 1957 and 13 January 1963. Each dot is a new record.
When Arizona Falls 1 WNW set new all-time records
Date
Kind
Detail
1957-06-24
Record high maximum temperature
Record high maximum temperature 47.8 C (118.0 F)
1958-07-11
Record high maximum temperature
Record high maximum temperature 48.3 C (118.9 F)
1963-01-13
Record low minimum temperature
Record low minimum temperature -9.4 C (15.1 F)
Wettest Day of Each Month
Aug: 69.3 mm (2.7 in)
The wettest day on record for each calendar month at Arizona Falls 1 WNW. The most was 69.3 mm (2.7 in) on 27 August 1951.
Record daily precipitation for each month at Arizona Falls 1 WNW
Month
Record daily precipitation (mm)
Date
Jan
36.3 mm (1.4 in)
30 January 1951
Feb
33.3 mm (1.3 in)
13 February 1931
Mar
34.3 mm (1.4 in)
14 March 1941
Apr
42.2 mm (1.7 in)
12 April 1941
May
19.6 mm (0.8 in)
5 May 1930
Jun
24.9 mm (1.0 in)
12 June 1955
Jul
44.2 mm (1.7 in)
17 July 1953
Aug
69.3 mm (2.7 in)
27 August 1951
Sep
67.1 mm (2.6 in)
4 September 1939
Oct
34.5 mm (1.4 in)
30 October 1959
Nov
26.2 mm (1.0 in)
13 November 1941
Dec
50.5 mm (2.0 in)
15 December 1932
Period of Record Coverage
1920 to 1963
Complete yearUnder 90 percent of days
44 years of record at Arizona Falls 1 WNW, 1920 to 1963. 5 years have data for under 90 percent of days and are left out of rankings: 1920, 1921, 1922, 1923, 1963.
Cooler than the station meanWarmer than the station mean
One stripe for each of 37 complete years at Arizona Falls 1 WNW, 1924 to 1962. Blue stripes are years cooler than the station's own mean of 21.2 C (70.1 F); red stripes are warmer. The coolest year was 1944, at 20.1 C (68.1 F), and the warmest was 1927, at 22.6 C (72.6 F). The strongest colour marks a difference of 1.4 C (2.5 F).
Annual mean temperature at Arizona Falls 1 WNW as warming stripes, 1924 to 1962
Year
Annual mean temperature
Difference from the station mean
1924
21.1 C
-0.11 C
1925
21.6 C
+0.45 C
1926
22.3 C
+1.09 C
1927
22.6 C
+1.38 C
1928
21.7 C
+0.52 C
1929
21.1 C
-0.05 C
1930
21.3 C
+0.08 C
1931
21.3 C
+0.15 C
1933
20.7 C
-0.52 C
1934
22.0 C
+0.83 C
1935
20.2 C
-0.93 C
1936
21.2 C
+0.01 C
1937
20.8 C
-0.34 C
1938
20.9 C
-0.25 C
1939
21.3 C
+0.15 C
1940
22.3 C
+1.09 C
1941
20.2 C
-0.97 C
1942
20.5 C
-0.63 C
1943
21.3 C
+0.08 C
1944
20.1 C
-1.11 C
1945
20.6 C
-0.60 C
1946
21.0 C
-0.16 C
1947
21.3 C
+0.12 C
1948
20.5 C
-0.72 C
1949
20.3 C
-0.85 C
1950
21.2 C
+0.07 C
1951
20.5 C
-0.71 C
1952
20.4 C
-0.82 C
1953
20.6 C
-0.55 C
1954
22.0 C
+0.81 C
1955
20.4 C
-0.75 C
1956
21.4 C
+0.27 C
1957
21.5 C
+0.32 C
1958
21.9 C
+0.77 C
1960
21.9 C
+0.74 C
1961
22.0 C
+0.81 C
1962
21.5 C
+0.30 C
The fitted trend in annual mean temperature here over 1924 to 1962 is -0.1 C (-0.3 to 0.1) per decade. The interval includes zero, so the trend is not clearly different from zero. In Fahrenheit: -0.1 F (-0.5 to 0.3) per decade. The slope is a straight line fitted to 37 complete years; the brackets give its 95 percent interval.
Fitted temperature trends per decade at Arizona Falls 1 WNW
Measure
Per decade (C)
Per decade (F)
Period
Complete years
Reading
Annual mean temperature
-0.1 C (-0.3 to 0.1) per decade
-0.1 F (-0.5 to 0.3) per decade
1924 to 1962
37
Not clearly different from zero
Mean daily maximum
0.25 C (0.03 to 0.47) per decade
0.45 F (0.05 to 0.85) per decade
1924 to 1962
37
Rise
Mean daily minimum
-0.4 C (-0.6 to -0.1) per decade
-0.7 F (-1.1 to -0.2) per decade
1924 to 1962
37
Fall
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
1920 to 1963
Yearly extremes at Arizona Falls 1 WNW: the record and the median year
Measure
Record
Year of the record
Median year
Years with a value
Hottest day (TXx)
48.3 C (118.9 F)
1958
44.7 C (112.5 F)
44
Coldest night (TNn)
-9.4 C (15.1 F)
1963
-4.1 C (24.5 F)
44
Wettest day (Rx1day)
69.3 mm (2.7 in)
1951
28.2 mm (1.1 in)
38
Wettest five days (Rx5day)
113.3 mm (4.5 in)
1951
39.6 mm (1.6 in)
38
Longest dry spell (CDD)
186 days
1962
80 days
38
Hottest day (TXx)
The hottest day of the year at Arizona Falls 1 WNW, 1920 to 1963. The record is 48.3 C (118.9 F) in 1958, marked on the chart; the median year is 44.7 C (112.5 F).
Hottest day (TXx) at Arizona Falls 1 WNW by year
Year
Hottest day (TXx)
1920
27.8 C (82.0 F)
1921
43.3 C (109.9 F)
1922
38.9 C (102.0 F)
1923
43.9 C (111.0 F)
1924
44.4 C (111.9 F)
1925
46.7 C (116.1 F)
1926
46.1 C (115.0 F)
1927
46.1 C (115.0 F)
1928
43.9 C (111.0 F)
1929
46.1 C (115.0 F)
1930
44.4 C (111.9 F)
1931
44.4 C (111.9 F)
1932
43.9 C (111.0 F)
1933
44.4 C (111.9 F)
1934
44.4 C (111.9 F)
1935
43.9 C (111.0 F)
1936
43.9 C (111.0 F)
1937
45.0 C (113.0 F)
1938
44.4 C (111.9 F)
1939
45.0 C (113.0 F)
1940
46.7 C (116.1 F)
1941
42.8 C (109.0 F)
1942
45.6 C (114.1 F)
1943
46.1 C (115.0 F)
1944
44.4 C (111.9 F)
1945
46.1 C (115.0 F)
1946
45.0 C (113.0 F)
1947
46.7 C (116.1 F)
1948
44.4 C (111.9 F)
1949
43.3 C (109.9 F)
1950
45.6 C (114.1 F)
1951
43.9 C (111.0 F)
1952
42.8 C (109.0 F)
1953
46.7 C (116.1 F)
1954
46.7 C (116.1 F)
1955
46.7 C (116.1 F)
1956
46.1 C (115.0 F)
1957
47.8 C (118.0 F)
1958
48.3 C (118.9 F)
1959
46.7 C (116.1 F)
1960
47.2 C (117.0 F)
1961
46.1 C (115.0 F)
1962
44.4 C (111.9 F)
1963
41.7 C (107.1 F)
Coldest night (TNn)
The coldest night of the year at Arizona Falls 1 WNW, 1920 to 1963. The record is -9.4 C (15.1 F) in 1963, marked on the chart; the median year is -4.1 C (24.5 F).
Coldest night (TNn) at Arizona Falls 1 WNW by year
Year
Coldest night (TNn)
1920
0.0 C (32.0 F)
1921
0.0 C (32.0 F)
1922
-1.1 C (30.0 F)
1923
-2.8 C (27.0 F)
1924
-3.9 C (25.0 F)
1925
-5.6 C (21.9 F)
1926
-3.9 C (25.0 F)
1927
-1.7 C (28.9 F)
1928
-3.3 C (26.1 F)
1929
-3.3 C (26.1 F)
1930
-3.9 C (25.0 F)
1931
-3.9 C (25.0 F)
1932
-5.6 C (21.9 F)
1933
-6.1 C (21.0 F)
1934
-5.6 C (21.9 F)
1935
-5.6 C (21.9 F)
1936
-3.9 C (25.0 F)
1937
-7.8 C (18.0 F)
1938
-1.7 C (28.9 F)
1939
-4.4 C (24.1 F)
1940
-3.9 C (25.0 F)
1941
-2.8 C (27.0 F)
1942
-3.3 C (26.1 F)
1943
-4.4 C (24.1 F)
1944
-3.3 C (26.1 F)
1945
-5.0 C (23.0 F)
1946
-3.9 C (25.0 F)
1947
-5.0 C (23.0 F)
1948
-6.7 C (19.9 F)
1949
-6.7 C (19.9 F)
1950
-7.8 C (18.0 F)
1951
-4.4 C (24.1 F)
1952
-3.9 C (25.0 F)
1953
-5.6 C (21.9 F)
1954
-6.1 C (21.0 F)
1955
-6.7 C (19.9 F)
1956
-5.6 C (21.9 F)
1957
-3.3 C (26.1 F)
1958
-3.9 C (25.0 F)
1959
-4.4 C (24.1 F)
1960
-5.6 C (21.9 F)
1961
-2.2 C (28.0 F)
1962
-6.1 C (21.0 F)
1963
-9.4 C (15.1 F)
Wettest day (Rx1day)
The wettest day of the year at Arizona Falls 1 WNW, 1920 to 1963. The record is 69.3 mm (2.7 in) in 1951, marked on the chart; the median year is 28.2 mm (1.1 in).
Wettest day (Rx1day) at Arizona Falls 1 WNW by year
Year
Wettest day (Rx1day)
1920
n/a
1921
n/a
1922
0.0 mm (0.00 in)
1923
n/a
1924
n/a
1925
n/a
1926
n/a
1927
26.7 mm (1.1 in)
1928
33.8 mm (1.3 in)
1929
27.9 mm (1.1 in)
1930
25.9 mm (1.0 in)
1931
33.3 mm (1.3 in)
1932
50.5 mm (2.0 in)
1933
23.9 mm (0.9 in)
1934
33.0 mm (1.3 in)
1935
40.4 mm (1.6 in)
1936
38.1 mm (1.5 in)
1937
28.4 mm (1.1 in)
1938
27.9 mm (1.1 in)
1939
67.1 mm (2.6 in)
1940
44.7 mm (1.8 in)
1941
42.2 mm (1.7 in)
1942
19.8 mm (0.8 in)
1943
66.5 mm (2.6 in)
1944
24.9 mm (1.0 in)
1945
37.1 mm (1.5 in)
1946
61.2 mm (2.4 in)
1947
10.4 mm (0.4 in)
1948
19.3 mm (0.8 in)
1949
20.6 mm (0.8 in)
1950
37.6 mm (1.5 in)
1951
69.3 mm (2.7 in)
1952
25.7 mm (1.0 in)
1953
44.2 mm (1.7 in)
1954
21.6 mm (0.9 in)
1955
38.1 mm (1.5 in)
1956
12.7 mm (0.5 in)
1957
26.7 mm (1.1 in)
1958
36.8 mm (1.4 in)
1959
34.5 mm (1.4 in)
1960
21.6 mm (0.9 in)
1961
22.1 mm (0.9 in)
1962
18.8 mm (0.7 in)
1963
18.8 mm (0.7 in)
Wettest five days (Rx5day)
The wettest five days of the year at Arizona Falls 1 WNW, 1920 to 1963. The record is 113.3 mm (4.5 in) in 1951, marked on the chart; the median year is 39.6 mm (1.6 in).
Wettest five days (Rx5day) at Arizona Falls 1 WNW by year
Year
Wettest five days (Rx5day)
1920
n/a
1921
n/a
1922
0.0 mm (0.00 in)
1923
n/a
1924
n/a
1925
n/a
1926
n/a
1927
26.7 mm (1.1 in)
1928
33.8 mm (1.3 in)
1929
37.4 mm (1.5 in)
1930
34.6 mm (1.4 in)
1931
82.8 mm (3.3 in)
1932
50.5 mm (2.0 in)
1933
44.2 mm (1.7 in)
1934
33.5 mm (1.3 in)
1935
54.2 mm (2.1 in)
1936
54.6 mm (2.1 in)
1937
40.9 mm (1.6 in)
1938
40.1 mm (1.6 in)
1939
85.2 mm (3.4 in)
1940
69.3 mm (2.7 in)
1941
69.3 mm (2.7 in)
1942
25.1 mm (1.0 in)
1943
70.8 mm (2.8 in)
1944
48.7 mm (1.9 in)
1945
37.1 mm (1.5 in)
1946
63.7 mm (2.5 in)
1947
12.9 mm (0.5 in)
1948
27.9 mm (1.1 in)
1949
34.8 mm (1.4 in)
1950
41.9 mm (1.6 in)
1951
113.3 mm (4.5 in)
1952
29.5 mm (1.2 in)
1953
47.8 mm (1.9 in)
1954
29.2 mm (1.1 in)
1955
79.2 mm (3.1 in)
1956
14.0 mm (0.6 in)
1957
39.1 mm (1.5 in)
1958
48.7 mm (1.9 in)
1959
48.2 mm (1.9 in)
1960
23.2 mm (0.9 in)
1961
29.0 mm (1.1 in)
1962
35.6 mm (1.4 in)
1963
30.2 mm (1.2 in)
Longest dry spell (CDD)
The longest dry spell of the year at Arizona Falls 1 WNW, 1920 to 1963. The record is 186 days in 1962, marked on the chart; the median year is 80 days.
Longest dry spell (CDD) at Arizona Falls 1 WNW by year
Year
Longest dry spell (CDD)
1920
n/a
1921
n/a
1922
31 days
1923
n/a
1924
n/a
1925
n/a
1926
n/a
1927
39 days
1928
148 days
1929
104 days
1930
44 days
1931
95 days
1932
62 days
1933
111 days
1934
42 days
1935
53 days
1936
104 days
1937
73 days
1938
102 days
1939
65 days
1940
105 days
1941
75 days
1942
76 days
1943
111 days
1944
73 days
1945
120 days
1946
154 days
1947
87 days
1948
79 days
1949
45 days
1950
88 days
1951
64 days
1952
46 days
1953
80 days
1954
89 days
1955
73 days
1956
101 days
1957
35 days
1958
44 days
1959
87 days
1960
96 days
1961
94 days
1962
186 days
1963
37 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
35 years with a frost
Across 35 years with a frost, the median last spring frost at Arizona Falls 1 WNW falls on 2 March and the median first autumn frost on 25 November, which leaves a median of 276 days between them.
Fitted over all years, the growing season changes by -9.5 days per decade at this station.
Frost dates and growing season at Arizona Falls 1 WNW
Measure
Median, all years
Earliest period
Recent period (1930 to 1962)
Recent against earliest
Fitted trend
Last spring frost
2 March
n/a
8 March
n/a
+6.4 days per decade
First autumn frost
25 November
n/a
21 November
n/a
-3.0 days per decade
Growing days
276 days
n/a
270 days
n/a
-9.5 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
33 years, 1928 to 1962
A day with at least 31.0 mm (1.2 in) of rain is expected about once in 2 years. A day with at least 86.8 mm (3.4 in) of rain is expected about once in 100 years.
Rainfall return levels at Arizona Falls 1 WNW: the daily rain expected about once in a given number of years
Expected about once in
A day with at least
Note
2 years
31.0 mm (1.2 in)
5 years
44.7 mm (1.8 in)
10 years
54.3 mm (2.1 in)
25 years
66.9 mm (2.6 in)
50 years
76.7 mm (3.0 in)
Longer than the 33 years of record
100 years
86.8 mm (3.4 in)
Longer than the 33 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, 33 years of values from 1928 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: 69.3 mm (2.7 in) in 1951; 67.1 mm (2.6 in) in 1939; 66.5 mm (2.6 in) in 1943.
Download the Data
Data for Arizona Falls 1 WNW standing records by year: CSV or JSON. Field meanings are on the data page.
Data for Arizona Falls 1 WNW 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.