Record envelope, standing records and threshold days for Donner Mem Sp (USC00042467), California, United States, with 63 years of record.
Key Facts for Donner Mem Sp
Donner Mem Sp (USC00042467) is a weather station in California, United States at 39.32 latitude and -120.23 longitude, 1,810 m (5,937 ft) above sea level.
The station reports from 1953 to 2015, 63 years of record.
1,464 records set at Donner Mem Sp still stand.
Records are tracked for tmax, tmin, prcp, snow, snwd: an element needs 30 years of data to be eligible.
Donner Mem Sp set a daily record high minimum temperature of 8.9 C (48.0 F) on 31 May 2015.
About the Station
Location: California, United States, 39.32 latitude, -120.23 longitude.
Elevation: 1,810 m (5,937 ft).
Period of record: 1953 to 2015, 63 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 Donner Mem Sp. 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 Donner Mem Sp, 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)
-27.8 C (-18.0 F)
n/a
n/a
Feb
19.4 C (66.9 F)
-33.3 C (-27.9 F)
n/a
n/a
Mar
22.2 C (72.0 F)
-23.3 C (-9.9 F)
n/a
n/a
Apr
26.1 C (79.0 F)
-17.8 C (0.0 F)
n/a
n/a
May
31.1 C (88.0 F)
-12.2 C (10.0 F)
n/a
n/a
Jun
35.0 C (95.0 F)
-6.1 C (21.0 F)
n/a
n/a
Jul
37.2 C (99.0 F)
-5.0 C (23.0 F)
n/a
n/a
Aug
37.2 C (99.0 F)
-6.7 C (19.9 F)
n/a
n/a
Sep
35.6 C (96.1 F)
-8.9 C (16.0 F)
n/a
n/a
Oct
32.2 C (90.0 F)
-15.6 C (3.9 F)
n/a
n/a
Nov
23.9 C (75.0 F)
-19.4 C (-2.9 F)
n/a
n/a
Dec
19.4 C (66.9 F)
-30.6 C (-23.1 F)
n/a
n/a
Which Years Hold Standing Records
1,464 standing records
Year with most
1,464 records at Donner Mem Sp still stand. 1974 holds the most, with 75.
Standing records at Donner Mem Sp by the year they were set
Year set
Standing records
1953
1
1954
28
1955
58
1956
26
1957
35
1958
33
1959
32
1960
41
1961
29
1962
32
1963
38
1964
21
1965
18
1966
37
1967
22
1968
25
1969
21
1970
22
1971
38
1972
43
1973
28
1974
75
1975
29
1976
20
1977
22
1978
18
1979
10
1980
18
1981
28
1982
20
1983
17
1984
7
1985
24
1986
21
1987
25
1988
23
1989
29
1990
27
1991
11
1992
18
1993
19
1994
6
1995
18
1996
17
1997
12
1998
22
1999
18
2000
19
2001
14
2002
14
2003
23
2004
15
2005
7
2006
16
2007
17
2008
15
2009
19
2010
1
2011
14
2012
28
2013
25
2014
27
2015
28
All-Time Record Progression
4 new records
4 all-time records were set at Donner Mem Sp between 19 June 1985 and 30 June 2013. Each dot is a new record.
When Donner Mem Sp set new all-time records
Date
Kind
Detail
1985-06-19
Record high minimum temperature
Record high minimum temperature 15.6 C (60.1 F)
1990-12-22
Record low maximum temperature
Record low maximum temperature -12.8 C (9.0 F)
1996-12-22
Record daily snowfall
Record daily snowfall 121.9 cm (48.0 in)
2013-06-30
Record high minimum temperature
Record high minimum temperature 16.1 C (61.0 F)
Wettest Day of Each Month
Feb: 173.0 mm (6.8 in)
The wettest day on record for each calendar month at Donner Mem Sp. The most was 173.0 mm (6.8 in) on 1 February 1963.
Record daily precipitation for each month at Donner Mem Sp
Month
Record daily precipitation (mm)
Date
Jan
104.1 mm (4.1 in)
21 January 1964
Feb
173.0 mm (6.8 in)
1 February 1963
Mar
115.8 mm (4.6 in)
11 March 1995
Apr
84.6 mm (3.3 in)
3 April 1958
May
61.5 mm (2.4 in)
19 May 1957
Jun
34.5 mm (1.4 in)
3 June 2010
Jul
66.0 mm (2.6 in)
17 July 2014
Aug
47.0 mm (1.9 in)
15 August 1976
Sep
40.6 mm (1.6 in)
18 September 2011
Oct
101.6 mm (4.0 in)
13 October 1962
Nov
84.1 mm (3.3 in)
11 November 1983
Dec
165.1 mm (6.5 in)
23 December 1964
Period of Record Coverage
1953 to 2015
Complete yearUnder 90 percent of days
63 years of record at Donner Mem Sp, 1953 to 2015. 11 years have data for under 90 percent of days and are left out of rankings: 1953, 1957, 1964, 1990, 2001, 2003, 2004, 2007 and others.
Cooler than the station meanWarmer than the station mean
One stripe for each of 47 complete years at Donner Mem Sp, 1955 to 2014. Blue stripes are years cooler than the station's own mean of 6.1 C (43.1 F); red stripes are warmer. The coolest year was 1971, at 4.6 C (40.2 F), and the warmest was 2014, at 8.3 C (46.9 F). The strongest colour marks a difference of 2.2 C (4.0 F).
Annual mean temperature at Donner Mem Sp as warming stripes, 1955 to 2014
Year
Annual mean temperature
Difference from the station mean
1955
5.1 C
-1.03 C
1956
5.5 C
-0.68 C
1958
6.7 C
+0.56 C
1959
6.9 C
+0.77 C
1960
6.3 C
+0.18 C
1961
6.7 C
+0.55 C
1962
6.1 C
-0.09 C
1963
6.1 C
-0.10 C
1965
5.4 C
-0.75 C
1966
5.4 C
-0.76 C
1967
5.6 C
-0.53 C
1968
5.7 C
-0.45 C
1969
5.7 C
-0.48 C
1970
5.9 C
-0.25 C
1971
4.6 C
-1.60 C
1972
5.8 C
-0.32 C
1973
5.5 C
-0.70 C
1974
4.8 C
-1.31 C
1975
5.3 C
-0.84 C
1977
6.6 C
+0.45 C
1978
6.0 C
-0.15 C
1979
6.2 C
+0.09 C
1980
6.2 C
+0.02 C
1981
7.3 C
+1.19 C
1982
5.1 C
-1.04 C
1983
5.8 C
-0.32 C
1984
6.3 C
+0.14 C
1985
5.5 C
-0.64 C
1987
6.6 C
+0.45 C
1988
6.8 C
+0.68 C
1989
5.8 C
-0.38 C
1991
6.4 C
+0.24 C
1992
6.9 C
+0.76 C
1993
5.8 C
-0.35 C
1994
5.9 C
-0.26 C
1995
6.3 C
+0.12 C
1996
6.8 C
+0.63 C
1997
6.4 C
+0.22 C
1998
5.3 C
-0.81 C
1999
6.6 C
+0.49 C
2000
7.1 C
+0.93 C
2002
7.0 C
+0.84 C
2005
6.9 C
+0.70 C
2008
6.1 C
-0.06 C
2012
7.1 C
+0.92 C
2013
6.8 C
+0.63 C
2014
8.3 C
+2.13 C
The annual mean temperature here has risen by 0.2 C (0.1 to 0.3) per decade over 1955 to 2014. In Fahrenheit: 0.4 F (0.2 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 Donner Mem Sp
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 (0.2 to 0.6) per decade
1955 to 2014
47
Rise
Mean daily maximum
0.1 C (-0.1 to 0.2) per decade
0.1 F (-0.2 to 0.4) per decade
1955 to 2014
47
Not clearly different from zero
Mean daily minimum
0.4 C (0.2 to 0.5) per decade
0.7 F (0.4 to 0.9) per decade
1955 to 2014
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
1953 to 2015
Yearly extremes at Donner Mem Sp: the record and the median year
Measure
Record
Year of the record
Median year
Years with a value
Hottest day (TXx)
37.2 C (99.0 F)
1981
33.3 C (91.9 F)
63
Coldest night (TNn)
-33.3 C (-27.9 F)
1962
-21.1 C (-6.0 F)
63
Wettest day (Rx1day)
173.0 mm (6.8 in)
1963
75.9 mm (3.0 in)
63
Wettest five days (Rx5day)
453.3 mm (17.8 in)
1955
155.0 mm (6.1 in)
63
Longest dry spell (CDD)
125 days
2008
48 days
63
Hottest day (TXx)
The hottest day of the year at Donner Mem Sp, 1953 to 2015. The record is 37.2 C (99.0 F) in 1981, marked on the chart; the median year is 33.3 C (91.9 F).
Hottest day (TXx) at Donner Mem Sp by year
Year
Hottest day (TXx)
1953
25.0 C (77.0 F)
1954
33.3 C (91.9 F)
1955
35.6 C (96.1 F)
1956
33.9 C (93.0 F)
1957
33.3 C (91.9 F)
1958
32.8 C (91.0 F)
1959
34.4 C (93.9 F)
1960
35.6 C (96.1 F)
1961
34.4 C (93.9 F)
1962
32.8 C (91.0 F)
1963
32.2 C (90.0 F)
1964
33.9 C (93.0 F)
1965
30.0 C (86.0 F)
1966
32.2 C (90.0 F)
1967
32.8 C (91.0 F)
1968
32.8 C (91.0 F)
1969
33.9 C (93.0 F)
1970
32.2 C (90.0 F)
1971
33.3 C (91.9 F)
1972
36.7 C (98.1 F)
1973
33.9 C (93.0 F)
1974
32.8 C (91.0 F)
1975
33.9 C (93.0 F)
1976
33.3 C (91.9 F)
1977
33.9 C (93.0 F)
1978
34.4 C (93.9 F)
1979
35.0 C (95.0 F)
1980
34.4 C (93.9 F)
1981
37.2 C (99.0 F)
1982
32.8 C (91.0 F)
1983
35.0 C (95.0 F)
1984
32.8 C (91.0 F)
1985
35.0 C (95.0 F)
1986
35.0 C (95.0 F)
1987
33.3 C (91.9 F)
1988
35.0 C (95.0 F)
1989
31.7 C (89.1 F)
1990
33.3 C (91.9 F)
1991
32.8 C (91.0 F)
1992
33.3 C (91.9 F)
1993
33.3 C (91.9 F)
1994
32.2 C (90.0 F)
1995
30.6 C (87.1 F)
1996
32.2 C (90.0 F)
1997
32.8 C (91.0 F)
1998
33.3 C (91.9 F)
1999
33.3 C (91.9 F)
2000
33.9 C (93.0 F)
2001
33.3 C (91.9 F)
2002
37.2 C (99.0 F)
2003
35.6 C (96.1 F)
2004
32.8 C (91.0 F)
2005
33.9 C (93.0 F)
2006
34.4 C (93.9 F)
2007
36.7 C (98.1 F)
2008
33.3 C (91.9 F)
2009
32.8 C (91.0 F)
2010
33.3 C (91.9 F)
2011
31.7 C (89.1 F)
2012
33.3 C (91.9 F)
2013
35.0 C (95.0 F)
2014
34.4 C (93.9 F)
2015
26.1 C (79.0 F)
Coldest night (TNn)
The coldest night of the year at Donner Mem Sp, 1953 to 2015. The record is -33.3 C (-27.9 F) in 1962, marked on the chart; the median year is -21.1 C (-6.0 F).
Coldest night (TNn) at Donner Mem Sp by year
Year
Coldest night (TNn)
1953
-15.0 C (5.0 F)
1954
-22.8 C (-9.0 F)
1955
-28.3 C (-18.9 F)
1956
-26.7 C (-16.1 F)
1957
-27.8 C (-18.0 F)
1958
-18.3 C (-0.9 F)
1959
-22.2 C (-8.0 F)
1960
-24.4 C (-11.9 F)
1961
-20.6 C (-5.1 F)
1962
-33.3 C (-27.9 F)
1963
-23.3 C (-9.9 F)
1964
-17.8 C (0.0 F)
1965
-30.6 C (-23.1 F)
1966
-23.3 C (-9.9 F)
1967
-22.8 C (-9.0 F)
1968
-23.3 C (-9.9 F)
1969
-25.0 C (-13.0 F)
1970
-18.3 C (-0.9 F)
1971
-26.7 C (-16.1 F)
1972
-28.9 C (-20.0 F)
1973
-25.6 C (-14.1 F)
1974
-24.4 C (-11.9 F)
1975
-21.1 C (-6.0 F)
1976
-19.4 C (-2.9 F)
1977
-18.9 C (-2.0 F)
1978
-23.3 C (-9.9 F)
1979
-24.4 C (-11.9 F)
1980
-16.7 C (1.9 F)
1981
-18.9 C (-2.0 F)
1982
-23.3 C (-9.9 F)
1983
-17.2 C (1.0 F)
1984
-19.4 C (-2.9 F)
1985
-20.6 C (-5.1 F)
1986
-17.2 C (1.0 F)
1987
-20.0 C (-4.0 F)
1988
-22.8 C (-9.0 F)
1989
-32.8 C (-27.0 F)
1990
-26.7 C (-16.1 F)
1991
-15.0 C (5.0 F)
1992
-22.8 C (-9.0 F)
1993
-23.3 C (-9.9 F)
1994
-18.9 C (-2.0 F)
1995
-17.2 C (1.0 F)
1996
-18.3 C (-0.9 F)
1997
-21.7 C (-7.1 F)
1998
-22.8 C (-9.0 F)
1999
-19.4 C (-2.9 F)
2000
-16.7 C (1.9 F)
2001
-20.0 C (-4.0 F)
2002
-25.0 C (-13.0 F)
2003
-16.7 C (1.9 F)
2004
-20.0 C (-4.0 F)
2005
-16.7 C (1.9 F)
2006
-17.2 C (1.0 F)
2007
-21.1 C (-6.0 F)
2008
-21.1 C (-6.0 F)
2009
-22.8 C (-9.0 F)
2010
-14.4 C (6.1 F)
2011
-19.4 C (-2.9 F)
2012
-17.8 C (0.0 F)
2013
-25.6 C (-14.1 F)
2014
-15.6 C (3.9 F)
2015
-13.9 C (7.0 F)
Wettest day (Rx1day)
The wettest day of the year at Donner Mem Sp, 1953 to 2015. The record is 173.0 mm (6.8 in) in 1963, marked on the chart; the median year is 75.9 mm (3.0 in).
Wettest day (Rx1day) at Donner Mem Sp by year
Year
Wettest day (Rx1day)
1953
36.8 mm (1.4 in)
1954
69.3 mm (2.7 in)
1955
131.3 mm (5.2 in)
1956
75.4 mm (3.0 in)
1957
65.3 mm (2.6 in)
1958
84.6 mm (3.3 in)
1959
66.3 mm (2.6 in)
1960
92.7 mm (3.6 in)
1961
49.5 mm (1.9 in)
1962
101.6 mm (4.0 in)
1963
173.0 mm (6.8 in)
1964
165.1 mm (6.5 in)
1965
69.1 mm (2.7 in)
1966
58.9 mm (2.3 in)
1967
101.6 mm (4.0 in)
1968
55.9 mm (2.2 in)
1969
88.4 mm (3.5 in)
1970
63.5 mm (2.5 in)
1971
75.4 mm (3.0 in)
1972
48.3 mm (1.9 in)
1973
69.3 mm (2.7 in)
1974
63.2 mm (2.5 in)
1975
67.3 mm (2.6 in)
1976
47.0 mm (1.9 in)
1977
58.4 mm (2.3 in)
1978
69.9 mm (2.8 in)
1979
84.6 mm (3.3 in)
1980
94.0 mm (3.7 in)
1981
92.2 mm (3.6 in)
1982
125.0 mm (4.9 in)
1983
84.1 mm (3.3 in)
1984
64.8 mm (2.6 in)
1985
78.7 mm (3.1 in)
1986
103.9 mm (4.1 in)
1987
101.6 mm (4.0 in)
1988
76.2 mm (3.0 in)
1989
71.4 mm (2.8 in)
1990
43.2 mm (1.7 in)
1991
73.2 mm (2.9 in)
1992
80.5 mm (3.2 in)
1993
59.2 mm (2.3 in)
1994
58.4 mm (2.3 in)
1995
115.8 mm (4.6 in)
1996
66.5 mm (2.6 in)
1997
102.6 mm (4.0 in)
1998
66.5 mm (2.6 in)
1999
110.7 mm (4.4 in)
2000
70.4 mm (2.8 in)
2001
81.3 mm (3.2 in)
2002
75.9 mm (3.0 in)
2003
55.4 mm (2.2 in)
2004
83.3 mm (3.3 in)
2005
152.4 mm (6.0 in)
2006
77.0 mm (3.0 in)
2007
55.9 mm (2.2 in)
2008
84.3 mm (3.3 in)
2009
88.9 mm (3.5 in)
2010
69.3 mm (2.7 in)
2011
86.4 mm (3.4 in)
2012
102.9 mm (4.1 in)
2013
22.9 mm (0.9 in)
2014
100.6 mm (4.0 in)
2015
82.3 mm (3.2 in)
Wettest five days (Rx5day)
The wettest five days of the year at Donner Mem Sp, 1953 to 2015. The record is 453.3 mm (17.8 in) in 1955, marked on the chart; the median year is 155.0 mm (6.1 in).
Wettest five days (Rx5day) at Donner Mem Sp by year
Year
Wettest five days (Rx5day)
1953
54.3 mm (2.1 in)
1954
146.5 mm (5.8 in)
1955
453.3 mm (17.8 in)
1956
164.8 mm (6.5 in)
1957
134.1 mm (5.3 in)
1958
190.9 mm (7.5 in)
1959
119.7 mm (4.7 in)
1960
176.6 mm (7.0 in)
1961
70.1 mm (2.8 in)
1962
307.9 mm (12.1 in)
1963
339.2 mm (13.4 in)
1964
408.6 mm (16.1 in)
1965
143.7 mm (5.7 in)
1966
180.3 mm (7.1 in)
1967
263.4 mm (10.4 in)
1968
119.4 mm (4.7 in)
1969
199.1 mm (7.8 in)
1970
180.4 mm (7.1 in)
1971
226.0 mm (8.9 in)
1972
100.9 mm (4.0 in)
1973
186.9 mm (7.4 in)
1974
152.4 mm (6.0 in)
1975
137.7 mm (5.4 in)
1976
117.7 mm (4.6 in)
1977
126.8 mm (5.0 in)
1978
153.4 mm (6.0 in)
1979
168.9 mm (6.6 in)
1980
338.3 mm (13.3 in)
1981
208.1 mm (8.2 in)
1982
240.7 mm (9.5 in)
1983
138.2 mm (5.4 in)
1984
115.0 mm (4.5 in)
1985
155.0 mm (6.1 in)
1986
220.2 mm (8.7 in)
1987
224.6 mm (8.8 in)
1988
123.0 mm (4.8 in)
1989
103.4 mm (4.1 in)
1990
88.6 mm (3.5 in)
1991
175.5 mm (6.9 in)
1992
152.1 mm (6.0 in)
1993
190.2 mm (7.5 in)
1994
126.4 mm (5.0 in)
1995
241.3 mm (9.5 in)
1996
168.1 mm (6.6 in)
1997
293.6 mm (11.6 in)
1998
112.7 mm (4.4 in)
1999
246.7 mm (9.7 in)
2000
172.8 mm (6.8 in)
2001
141.9 mm (5.6 in)
2002
185.3 mm (7.3 in)
2003
117.3 mm (4.6 in)
2004
111.2 mm (4.4 in)
2005
229.8 mm (9.0 in)
2006
253.2 mm (10.0 in)
2007
140.4 mm (5.5 in)
2008
134.1 mm (5.3 in)
2009
144.0 mm (5.7 in)
2010
148.1 mm (5.8 in)
2011
147.6 mm (5.8 in)
2012
232.7 mm (9.2 in)
2013
44.5 mm (1.8 in)
2014
206.7 mm (8.1 in)
2015
150.6 mm (5.9 in)
Longest dry spell (CDD)
The longest dry spell of the year at Donner Mem Sp, 1953 to 2015. The record is 125 days in 2008, marked on the chart; the median year is 48 days.
Longest dry spell (CDD) at Donner Mem Sp by year
Year
Longest dry spell (CDD)
1953
13 days
1954
101 days
1955
62 days
1956
34 days
1957
48 days
1958
33 days
1959
87 days
1960
44 days
1961
42 days
1962
47 days
1963
37 days
1964
57 days
1965
39 days
1966
81 days
1967
47 days
1968
40 days
1969
93 days
1970
67 days
1971
38 days
1972
82 days
1973
41 days
1974
63 days
1975
53 days
1976
58 days
1977
76 days
1978
47 days
1979
39 days
1980
44 days
1981
75 days
1982
22 days
1983
38 days
1984
37 days
1985
65 days
1986
54 days
1987
85 days
1988
50 days
1989
59 days
1990
36 days
1991
26 days
1992
43 days
1993
69 days
1994
103 days
1995
96 days
1996
33 days
1997
47 days
1998
24 days
1999
62 days
2000
66 days
2001
107 days
2002
111 days
2003
45 days
2004
114 days
2005
101 days
2006
39 days
2007
83 days
2008
125 days
2009
43 days
2010
31 days
2011
26 days
2012
48 days
2013
64 days
2014
56 days
2015
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
47 years with a frost
Across 47 years with a frost, the median last spring frost at Donner Mem Sp falls on 25 June and the median first autumn frost on 13 July, which leaves a median of 23 days between them.
Fitted over all years, the growing season changes by +11.6 days per decade at this station.
Frost dates and growing season at Donner Mem Sp
Measure
Median, all years
Earliest period
Recent period (1974 to 2014)
Recent against earliest
Fitted trend
Last spring frost
25 June
n/a
21 June
n/a
-2.0 days per decade
First autumn frost
13 July
n/a
19 July
n/a
+9.6 days per decade
Growing days
23 days
n/a
28 days
n/a
+11.6 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
54 years, 1954 to 2014
A day with at least 75.9 mm (3.0 in) of rain is expected about once in 2 years. A day with at least 161.4 mm (6.4 in) of rain is expected about once in 100 years.
Rainfall return levels at Donner Mem Sp: the daily rain expected about once in a given number of years
Expected about once in
A day with at least
Note
2 years
75.9 mm (3.0 in)
5 years
98.1 mm (3.9 in)
10 years
113.1 mm (4.5 in)
25 years
132.3 mm (5.2 in)
50 years
146.8 mm (5.8 in)
100 years
161.4 mm (6.4 in)
Longer than the 54 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, 54 years of values from 1954 to 2014.
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: 173.0 mm (6.8 in) in 1963; 152.4 mm (6.0 in) in 2005; 131.3 mm (5.2 in) in 1955.
Station Changes
No change in the annual mean temperature of this station was found against its neighbours.
Download the Data
Data for Donner Mem Sp standing records by year: CSV or JSON. Field meanings are on the data page.
Data for Donner Mem Sp 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.