Record envelope, standing records and threshold days for Snowflake 15 W (USC00028018), Arizona, United States, with 34 years of record.
Key Facts for Snowflake 15 W
Snowflake 15 W (USC00028018) is a weather station in Arizona, United States at 34.50 latitude and -110.33 longitude, 1,853 m (6,080 ft) above sea level.
The station reports from 1965 to 1998, 34 years of record.
1,464 records set at Snowflake 15 W still stand.
Records are tracked for tmax, tmin, prcp, snow, snwd: an element needs 30 years of data to be eligible.
Snowflake 15 W set a daily record high minimum temperature of 2.2 C (36.0 F) on 24 February 1998.
About the Station
Location: Arizona, United States, 34.50 latitude, -110.33 longitude.
Elevation: 1,853 m (6,080 ft).
Period of record: 1965 to 1998, 34 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 Snowflake 15 W. 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 Snowflake 15 W, with 2026 drawn through them
Month
Highest record high
Lowest record low
2026 highest maximum
2026 lowest minimum
Jan
21.7 C (71.1 F)
-31.7 C (-25.1 F)
n/a
n/a
Feb
23.9 C (75.0 F)
-19.4 C (-2.9 F)
n/a
n/a
Mar
26.1 C (79.0 F)
-15.0 C (5.0 F)
n/a
n/a
Apr
29.4 C (84.9 F)
-11.7 C (10.9 F)
n/a
n/a
May
35.0 C (95.0 F)
-7.8 C (18.0 F)
n/a
n/a
Jun
37.8 C (100.0 F)
-2.2 C (28.0 F)
n/a
n/a
Jul
38.3 C (100.9 F)
3.9 C (39.0 F)
n/a
n/a
Aug
37.2 C (99.0 F)
3.3 C (37.9 F)
n/a
n/a
Sep
34.4 C (93.9 F)
-1.1 C (30.0 F)
n/a
n/a
Oct
30.0 C (86.0 F)
-10.0 C (14.0 F)
n/a
n/a
Nov
25.0 C (77.0 F)
-23.3 C (-9.9 F)
n/a
n/a
Dec
21.7 C (71.1 F)
-25.6 C (-14.1 F)
n/a
n/a
Which Years Hold Standing Records
1,464 standing records
Year with most
1,464 records at Snowflake 15 W still stand. 1971 holds the most, with 77.
Standing records at Snowflake 15 W by the year they were set
Year set
Standing records
1965
30
1966
57
1967
49
1968
47
1969
52
1970
51
1971
77
1972
45
1973
38
1974
50
1975
49
1976
27
1977
41
1978
50
1979
49
1980
46
1981
33
1982
29
1983
30
1984
27
1985
41
1986
49
1987
38
1988
40
1989
65
1990
55
1991
33
1992
47
1993
24
1994
28
1995
42
1996
74
1997
48
1998
3
All-Time Record Progression
2 new records
2 all-time records were set at Snowflake 15 W between 29 July 1995 and 3 August 1997. Each dot is a new record.
When Snowflake 15 W set new all-time records
Date
Kind
Detail
1995-07-29
Record high maximum temperature
Record high maximum temperature 38.3 C (100.9 F)
1997-08-03
Record high minimum temperature
Record high minimum temperature 23.9 C (75.0 F)
Wettest Day of Each Month
Jul: 90.9 mm (3.6 in)
The wettest day on record for each calendar month at Snowflake 15 W. The most was 90.9 mm (3.6 in) on 23 July 1968.
Record daily precipitation for each month at Snowflake 15 W
Month
Record daily precipitation (mm)
Date
Jan
25.1 mm (1.0 in)
31 January 1987
Feb
24.1 mm (0.9 in)
25 February 1995
Mar
25.4 mm (1.0 in)
27 March 1984
Apr
15.7 mm (0.6 in)
3 April 1977
May
32.8 mm (1.3 in)
6 May 1973
Jun
36.8 mm (1.4 in)
29 June 1981
Jul
90.9 mm (3.6 in)
23 July 1968
Aug
52.6 mm (2.1 in)
6 August 1997
Sep
66.0 mm (2.6 in)
30 September 1971
Oct
37.3 mm (1.5 in)
3 October 1984
Nov
30.5 mm (1.2 in)
12 November 1978
Dec
38.1 mm (1.5 in)
14 December 1967
Period of Record Coverage
1965 to 1998
Complete yearUnder 90 percent of days
34 years of record at Snowflake 15 W, 1965 to 1998. 3 years have data for under 90 percent of days and are left out of rankings: 1965, 1977, 1998.
Cooler than the station meanWarmer than the station mean
One stripe for each of 30 complete years at Snowflake 15 W, 1966 to 1997. Blue stripes are years cooler than the station's own mean of 10.9 C (51.7 F); red stripes are warmer. The coolest year was 1968, at 10.1 C (50.2 F), and the warmest was 1996, at 12.5 C (54.5 F). The strongest colour marks a difference of 1.6 C (2.9 F).
Annual mean temperature at Snowflake 15 W as warming stripes, 1966 to 1997
Year
Annual mean temperature
Difference from the station mean
1966
11.1 C
+0.12 C
1967
10.9 C
-0.10 C
1968
10.1 C
-0.84 C
1969
11.0 C
+0.04 C
1970
10.5 C
-0.49 C
1971
10.3 C
-0.68 C
1972
11.2 C
+0.20 C
1973
10.1 C
-0.83 C
1974
11.2 C
+0.20 C
1975
10.1 C
-0.84 C
1976
10.6 C
-0.35 C
1979
10.5 C
-0.46 C
1980
10.8 C
-0.12 C
1981
11.8 C
+0.84 C
1982
10.6 C
-0.38 C
1983
10.9 C
-0.01 C
1984
10.8 C
-0.11 C
1985
10.9 C
-0.03 C
1986
11.4 C
+0.48 C
1987
10.6 C
-0.40 C
1988
11.1 C
+0.15 C
1989
11.7 C
+0.78 C
1990
10.8 C
-0.14 C
1991
10.5 C
-0.50 C
1992
10.3 C
-0.62 C
1993
11.1 C
+0.10 C
1994
11.6 C
+0.65 C
1995
11.9 C
+0.97 C
1996
12.5 C
+1.54 C
1997
11.7 C
+0.71 C
The annual mean temperature here has risen by 0.3 C (0.1 to 0.5) per decade over 1966 to 1997. In Fahrenheit: 0.6 F (0.2 to 0.9) per decade. The slope is a straight line fitted to 30 complete years; the brackets give its 95 percent interval.
Fitted temperature trends per decade at Snowflake 15 W
Measure
Per decade (C)
Per decade (F)
Period
Complete years
Reading
Annual mean temperature
0.3 C (0.1 to 0.5) per decade
0.6 F (0.2 to 0.9) per decade
1966 to 1997
30
Rise
Mean daily maximum
0.6 C (0.4 to 0.9) per decade
1.1 F (0.7 to 1.6) per decade
1966 to 1997
30
Rise
Mean daily minimum
0.00 C (-0.20 to 0.21) per decade
0.01 F (-0.36 to 0.37) per decade
1966 to 1997
30
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
1965 to 1998
Yearly extremes at Snowflake 15 W: the record and the median year
Measure
Record
Year of the record
Median year
Years with a value
Hottest day (TXx)
38.3 C (100.9 F)
1995
35.0 C (95.0 F)
34
Coldest night (TNn)
-31.7 C (-25.1 F)
1971
-18.0 C (-0.5 F)
34
Wettest day (Rx1day)
90.9 mm (3.6 in)
1968
32.4 mm (1.3 in)
34
Wettest five days (Rx5day)
118.8 mm (4.7 in)
1968
47.5 mm (1.9 in)
34
Longest dry spell (CDD)
151 days
1972
54 days
34
Hottest day (TXx)
The hottest day of the year at Snowflake 15 W, 1965 to 1998. The record is 38.3 C (100.9 F) in 1995, marked on the chart; the median year is 35.0 C (95.0 F).
Hottest day (TXx) at Snowflake 15 W by year
Year
Hottest day (TXx)
1965
33.9 C (93.0 F)
1966
35.0 C (95.0 F)
1967
34.4 C (93.9 F)
1968
35.0 C (95.0 F)
1969
35.0 C (95.0 F)
1970
36.1 C (97.0 F)
1971
37.2 C (99.0 F)
1972
35.0 C (95.0 F)
1973
36.1 C (97.0 F)
1974
37.8 C (100.0 F)
1975
33.9 C (93.0 F)
1976
33.9 C (93.0 F)
1977
35.0 C (95.0 F)
1978
35.6 C (96.1 F)
1979
35.6 C (96.1 F)
1980
35.0 C (95.0 F)
1981
35.0 C (95.0 F)
1982
35.0 C (95.0 F)
1983
35.0 C (95.0 F)
1984
34.4 C (93.9 F)
1985
37.2 C (99.0 F)
1986
35.0 C (95.0 F)
1987
34.4 C (93.9 F)
1988
35.6 C (96.1 F)
1989
37.8 C (100.0 F)
1990
37.8 C (100.0 F)
1991
35.0 C (95.0 F)
1992
35.6 C (96.1 F)
1993
36.1 C (97.0 F)
1994
37.2 C (99.0 F)
1995
38.3 C (100.9 F)
1996
36.7 C (98.1 F)
1997
36.1 C (97.0 F)
1998
18.3 C (64.9 F)
Coldest night (TNn)
The coldest night of the year at Snowflake 15 W, 1965 to 1998. The record is -31.7 C (-25.1 F) in 1971, marked on the chart; the median year is -18.0 C (-0.5 F).
Coldest night (TNn) at Snowflake 15 W by year
Year
Coldest night (TNn)
1965
-13.9 C (7.0 F)
1966
-22.2 C (-8.0 F)
1967
-21.7 C (-7.1 F)
1968
-21.7 C (-7.1 F)
1969
-17.2 C (1.0 F)
1970
-23.9 C (-11.0 F)
1971
-31.7 C (-25.1 F)
1972
-19.4 C (-2.9 F)
1973
-13.3 C (8.1 F)
1974
-21.1 C (-6.0 F)
1975
-18.3 C (-0.9 F)
1976
-23.3 C (-9.9 F)
1977
-16.7 C (1.9 F)
1978
-24.4 C (-11.9 F)
1979
-25.0 C (-13.0 F)
1980
-15.6 C (3.9 F)
1981
-13.9 C (7.0 F)
1982
-17.8 C (0.0 F)
1983
-17.8 C (0.0 F)
1984
-13.9 C (7.0 F)
1985
-18.3 C (-0.9 F)
1986
-15.0 C (5.0 F)
1987
-20.6 C (-5.1 F)
1988
-17.8 C (0.0 F)
1989
-19.4 C (-2.9 F)
1990
-25.6 C (-14.1 F)
1991
-17.8 C (0.0 F)
1992
-20.6 C (-5.1 F)
1993
-16.1 C (3.0 F)
1994
-16.7 C (1.9 F)
1995
-12.8 C (9.0 F)
1996
-16.7 C (1.9 F)
1997
-18.9 C (-2.0 F)
1998
-9.4 C (15.1 F)
Wettest day (Rx1day)
The wettest day of the year at Snowflake 15 W, 1965 to 1998. The record is 90.9 mm (3.6 in) in 1968, marked on the chart; the median year is 32.4 mm (1.3 in).
Wettest day (Rx1day) at Snowflake 15 W by year
Year
Wettest day (Rx1day)
1965
35.6 mm (1.4 in)
1966
29.7 mm (1.2 in)
1967
38.1 mm (1.5 in)
1968
90.9 mm (3.6 in)
1969
38.4 mm (1.5 in)
1970
32.0 mm (1.3 in)
1971
66.0 mm (2.6 in)
1972
22.9 mm (0.9 in)
1973
32.8 mm (1.3 in)
1974
36.3 mm (1.4 in)
1975
20.8 mm (0.8 in)
1976
23.6 mm (0.9 in)
1977
34.8 mm (1.4 in)
1978
30.5 mm (1.2 in)
1979
18.5 mm (0.7 in)
1980
25.4 mm (1.0 in)
1981
36.8 mm (1.4 in)
1982
35.6 mm (1.4 in)
1983
30.5 mm (1.2 in)
1984
41.7 mm (1.6 in)
1985
30.5 mm (1.2 in)
1986
22.6 mm (0.9 in)
1987
25.1 mm (1.0 in)
1988
30.5 mm (1.2 in)
1989
38.1 mm (1.5 in)
1990
22.9 mm (0.9 in)
1991
27.2 mm (1.1 in)
1992
45.0 mm (1.8 in)
1993
33.5 mm (1.3 in)
1994
25.9 mm (1.0 in)
1995
33.5 mm (1.3 in)
1996
37.6 mm (1.5 in)
1997
52.6 mm (2.1 in)
1998
3.8 mm (0.15 in)
Wettest five days (Rx5day)
The wettest five days of the year at Snowflake 15 W, 1965 to 1998. The record is 118.8 mm (4.7 in) in 1968, marked on the chart; the median year is 47.5 mm (1.9 in).
Wettest five days (Rx5day) at Snowflake 15 W by year
Year
Wettest five days (Rx5day)
1965
44.5 mm (1.8 in)
1966
49.0 mm (1.9 in)
1967
50.6 mm (2.0 in)
1968
118.8 mm (4.7 in)
1969
47.7 mm (1.9 in)
1970
37.1 mm (1.5 in)
1971
81.5 mm (3.2 in)
1972
48.3 mm (1.9 in)
1973
35.8 mm (1.4 in)
1974
48.1 mm (1.9 in)
1975
30.7 mm (1.2 in)
1976
38.6 mm (1.5 in)
1977
36.3 mm (1.4 in)
1978
43.1 mm (1.7 in)
1979
32.6 mm (1.3 in)
1980
34.3 mm (1.4 in)
1981
57.9 mm (2.3 in)
1982
52.9 mm (2.1 in)
1983
52.9 mm (2.1 in)
1984
65.3 mm (2.6 in)
1985
70.1 mm (2.8 in)
1986
39.2 mm (1.5 in)
1987
47.2 mm (1.9 in)
1988
41.4 mm (1.6 in)
1989
40.6 mm (1.6 in)
1990
37.6 mm (1.5 in)
1991
45.9 mm (1.8 in)
1992
84.1 mm (3.3 in)
1993
55.9 mm (2.2 in)
1994
60.9 mm (2.4 in)
1995
44.2 mm (1.7 in)
1996
65.5 mm (2.6 in)
1997
55.9 mm (2.2 in)
1998
3.8 mm (0.15 in)
Longest dry spell (CDD)
The longest dry spell of the year at Snowflake 15 W, 1965 to 1998. The record is 151 days in 1972, marked on the chart; the median year is 54 days.
Longest dry spell (CDD) at Snowflake 15 W by year
Year
Longest dry spell (CDD)
1965
38 days
1966
83 days
1967
55 days
1968
65 days
1969
58 days
1970
52 days
1971
78 days
1972
151 days
1973
66 days
1974
96 days
1975
68 days
1976
40 days
1977
48 days
1978
64 days
1979
42 days
1980
51 days
1981
56 days
1982
54 days
1983
38 days
1984
57 days
1985
21 days
1986
73 days
1987
28 days
1988
46 days
1989
54 days
1990
30 days
1991
64 days
1992
31 days
1993
55 days
1994
30 days
1995
57 days
1996
50 days
1997
42 days
1998
48 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
30 years with a frost
Across 30 years with a frost, the median last spring frost at Snowflake 15 W falls on 21 May and the median first autumn frost on 14 October, which leaves a median of 145 days between them.
Fitted over all years, the growing season changes by -2.3 days per decade at this station.
Frost dates and growing season at Snowflake 15 W
Measure
Median, all years
Earliest period
Recent period (1966 to 1997)
Recent against earliest
Fitted trend
Last spring frost
21 May
n/a
21 May
n/a
+4.4 days per decade
First autumn frost
14 October
n/a
14 October
n/a
+2.1 days per decade
Growing days
145 days
n/a
145 days
n/a
-2.3 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
32 years, 1966 to 1997
A day with at least 31.1 mm (1.2 in) of rain is expected about once in 2 years. A day with at least 88.9 mm (3.5 in) of rain is expected about once in 100 years.
Rainfall return levels at Snowflake 15 W: the daily rain expected about once in a given number of years
Expected about once in
A day with at least
Note
2 years
31.1 mm (1.2 in)
5 years
41.5 mm (1.6 in)
10 years
50.0 mm (2.0 in)
25 years
63.2 mm (2.5 in)
50 years
75.0 mm (3.0 in)
Longer than the 32 years of record
100 years
88.9 mm (3.5 in)
Longer than the 32 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, 32 years of values from 1966 to 1997.
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: 90.9 mm (3.6 in) in 1968; 66.0 mm (2.6 in) in 1971; 52.6 mm (2.1 in) in 1997.
Download the Data
Data for Snowflake 15 W standing records by year: CSV or JSON. Field meanings are on the data page.
Data for Snowflake 15 W 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.