Record envelope, standing records and threshold days for Richardson Gr Sp (USC00047404), California, United States, with 52 years of record.
Key Facts for Richardson Gr Sp
Richardson Gr Sp (USC00047404) is a weather station in California, United States at 40.03 latitude and -123.79 longitude, 153 m (503 ft) above sea level.
The station reports from 1961 to 2012, 52 years of record.
1,464 records set at Richardson Gr Sp still stand.
Records are tracked for tmax, tmin, prcp, snow, snwd: an element needs 30 years of data to be eligible.
Richardson Gr Sp tied a daily record low minimum temperature of 6.1 C (43.0 F) on 18 August 2012.
About the Station
Location: California, United States, 40.03 latitude, -123.79 longitude.
Elevation: 153 m (503 ft).
Period of record: 1961 to 2012, 52 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 Richardson Gr 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 Richardson Gr Sp, with 2026 drawn through them
Month
Highest record high
Lowest record low
2026 highest maximum
2026 lowest minimum
Jan
18.9 C (66.0 F)
-6.1 C (21.0 F)
n/a
n/a
Feb
25.0 C (77.0 F)
-6.7 C (19.9 F)
n/a
n/a
Mar
27.8 C (82.0 F)
-2.8 C (27.0 F)
n/a
n/a
Apr
32.8 C (91.0 F)
-5.0 C (23.0 F)
n/a
n/a
May
38.3 C (100.9 F)
-5.0 C (23.0 F)
n/a
n/a
Jun
42.2 C (108.0 F)
1.1 C (34.0 F)
n/a
n/a
Jul
44.4 C (111.9 F)
-0.6 C (30.9 F)
n/a
n/a
Aug
44.4 C (111.9 F)
5.6 C (42.1 F)
n/a
n/a
Sep
41.1 C (106.0 F)
3.3 C (37.9 F)
n/a
n/a
Oct
37.8 C (100.0 F)
-2.2 C (28.0 F)
n/a
n/a
Nov
26.1 C (79.0 F)
-3.3 C (26.1 F)
n/a
n/a
Dec
20.6 C (69.1 F)
-9.4 C (15.1 F)
n/a
n/a
Which Years Hold Standing Records
1,464 standing records
Year with most
1,464 records at Richardson Gr Sp still stand. 1972 holds the most, with 58.
Standing records at Richardson Gr Sp by the year they were set
Year set
Standing records
1961
4
1962
36
1963
33
1964
46
1965
49
1966
36
1967
44
1968
31
1969
33
1970
38
1971
39
1972
58
1973
27
1974
35
1975
35
1976
30
1977
34
1978
37
1979
27
1980
23
1981
29
1982
25
1983
20
1984
28
1985
36
1986
18
1987
35
1988
17
1989
36
1990
53
1991
32
1992
17
1993
30
1994
21
1995
38
1996
33
1997
23
1998
23
1999
21
2000
12
2001
19
2002
31
2003
43
2004
32
2005
12
2006
8
2007
15
2008
19
2009
17
2010
20
2011
5
2012
1
All-Time Record Progression
1 new records
1 all-time records were set at Richardson Gr Sp between 20 December 1998 and 20 December 1998. Each dot is a new record.
When Richardson Gr Sp set new all-time records
Date
Kind
Detail
1998-12-20
Record daily snowfall
Record daily snowfall 8.9 cm (3.5 in)
Wettest Day of Each Month
Dec: 287.0 mm (11.3 in)
The wettest day on record for each calendar month at Richardson Gr Sp. The most was 287.0 mm (11.3 in) on 22 December 1964.
Record daily precipitation for each month at Richardson Gr Sp
Month
Record daily precipitation (mm)
Date
Jan
200.7 mm (7.9 in)
16 January 1974
Feb
144.8 mm (5.7 in)
17 February 1986
Mar
174.5 mm (6.9 in)
9 March 1995
Apr
82.0 mm (3.2 in)
1 April 1974
May
92.7 mm (3.6 in)
27 May 1990
Jun
61.0 mm (2.4 in)
18 June 2005
Jul
19.8 mm (0.8 in)
8 July 1974
Aug
61.0 mm (2.4 in)
31 August 1983
Sep
65.0 mm (2.6 in)
17 September 1986
Oct
117.6 mm (4.6 in)
12 October 1962
Nov
147.8 mm (5.8 in)
26 November 1962
Dec
287.0 mm (11.3 in)
22 December 1964
Period of Record Coverage
1961 to 2012
Complete yearUnder 90 percent of days
52 years of record at Richardson Gr Sp, 1961 to 2012. 9 years have data for under 90 percent of days and are left out of rankings: 1961, 2004, 2005, 2006, 2007, 2008, 2010, 2011 and others.
Cooler than the station meanWarmer than the station mean
One stripe for each of 38 complete years at Richardson Gr Sp, 1963 to 2009. Blue stripes are years cooler than the station's own mean of 13.2 C (55.8 F); red stripes are warmer. The coolest year was 1975, at 12.4 C (54.3 F), and the warmest was 1981, at 13.9 C (57.1 F). The strongest colour marks a difference of 0.9 C (1.6 F).
Annual mean temperature at Richardson Gr Sp as warming stripes, 1963 to 2009
Year
Annual mean temperature
Difference from the station mean
1963
13.4 C
+0.17 C
1964
13.1 C
-0.10 C
1965
13.4 C
+0.22 C
1966
13.7 C
+0.48 C
1967
13.7 C
+0.51 C
1968
13.8 C
+0.58 C
1969
13.4 C
+0.14 C
1970
13.9 C
+0.68 C
1971
12.7 C
-0.55 C
1972
13.4 C
+0.13 C
1973
13.5 C
+0.29 C
1974
13.2 C
-0.07 C
1975
12.4 C
-0.82 C
1976
12.4 C
-0.80 C
1977
13.2 C
-0.03 C
1978
13.7 C
+0.50 C
1979
13.6 C
+0.36 C
1980
13.5 C
+0.23 C
1981
13.9 C
+0.71 C
1982
12.7 C
-0.55 C
1983
13.4 C
+0.20 C
1984
13.0 C
-0.19 C
1985
12.7 C
-0.49 C
1987
13.6 C
+0.36 C
1988
13.2 C
+0.01 C
1989
12.4 C
-0.80 C
1990
12.9 C
-0.32 C
1991
13.0 C
-0.27 C
1993
12.6 C
-0.61 C
1994
12.8 C
-0.41 C
1995
13.7 C
+0.52 C
1996
13.9 C
+0.69 C
1997
13.4 C
+0.16 C
1998
13.1 C
-0.09 C
2001
12.9 C
-0.33 C
2002
13.2 C
+0.01 C
2003
13.2 C
0.00 C
2009
12.8 C
-0.40 C
The fitted trend in annual mean temperature here over 1963 to 2009 is -0.09 C (-0.20 to 0.03) per decade. The interval includes zero, so the trend is not clearly different from zero. In Fahrenheit: -0.16 F (-0.37 to 0.05) per decade. The slope is a straight line fitted to 38 complete years; the brackets give its 95 percent interval.
Fitted temperature trends per decade at Richardson Gr Sp
Measure
Per decade (C)
Per decade (F)
Period
Complete years
Reading
Annual mean temperature
-0.09 C (-0.20 to 0.03) per decade
-0.16 F (-0.37 to 0.05) per decade
1963 to 2009
38
Not clearly different from zero
Mean daily maximum
-0.2 C (-0.4 to -0.1) per decade
-0.4 F (-0.7 to -0.2) per decade
1963 to 2009
38
Fall
Mean daily minimum
0.1 C (-0.1 to 0.2) per decade
0.1 F (-0.2 to 0.4) per decade
1963 to 2009
38
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
1961 to 2012
Yearly extremes at Richardson Gr Sp: the record and the median year
Measure
Record
Year of the record
Median year
Years with a value
Hottest day (TXx)
44.4 C (111.9 F)
1972
39.4 C (102.9 F)
52
Coldest night (TNn)
-9.4 C (15.1 F)
1990
-3.0 C (26.5 F)
52
Wettest day (Rx1day)
287.0 mm (11.3 in)
1964
115.4 mm (4.5 in)
52
Wettest five days (Rx5day)
696.5 mm (27.4 in)
1964
260.9 mm (10.3 in)
52
Longest dry spell (CDD)
162 days
2002
81 days
52
Hottest day (TXx)
The hottest day of the year at Richardson Gr Sp, 1961 to 2012. The record is 44.4 C (111.9 F) in 1972, marked on the chart; the median year is 39.4 C (102.9 F).
Hottest day (TXx) at Richardson Gr Sp by year
Year
Hottest day (TXx)
1961
18.9 C (66.0 F)
1962
40.0 C (104.0 F)
1963
39.4 C (102.9 F)
1964
42.2 C (108.0 F)
1965
39.4 C (102.9 F)
1966
42.2 C (108.0 F)
1967
42.2 C (108.0 F)
1968
40.0 C (104.0 F)
1969
40.0 C (104.0 F)
1970
40.6 C (105.1 F)
1971
41.1 C (106.0 F)
1972
44.4 C (111.9 F)
1973
41.1 C (106.0 F)
1974
41.1 C (106.0 F)
1975
39.4 C (102.9 F)
1976
38.3 C (100.9 F)
1977
40.0 C (104.0 F)
1978
44.4 C (111.9 F)
1979
39.4 C (102.9 F)
1980
42.2 C (108.0 F)
1981
43.3 C (109.9 F)
1982
40.6 C (105.1 F)
1983
37.2 C (99.0 F)
1984
38.3 C (100.9 F)
1985
40.0 C (104.0 F)
1986
37.2 C (99.0 F)
1987
40.0 C (104.0 F)
1988
40.0 C (104.0 F)
1989
35.0 C (95.0 F)
1990
38.9 C (102.0 F)
1991
38.9 C (102.0 F)
1992
40.6 C (105.1 F)
1993
39.4 C (102.9 F)
1994
38.9 C (102.0 F)
1995
37.2 C (99.0 F)
1996
39.4 C (102.9 F)
1997
36.7 C (98.1 F)
1998
40.6 C (105.1 F)
1999
38.9 C (102.0 F)
2000
37.2 C (99.0 F)
2001
37.2 C (99.0 F)
2002
39.4 C (102.9 F)
2003
40.6 C (105.1 F)
2004
37.8 C (100.0 F)
2005
38.3 C (100.9 F)
2006
34.4 C (93.9 F)
2007
36.1 C (97.0 F)
2008
37.8 C (100.0 F)
2009
37.8 C (100.0 F)
2010
37.2 C (99.0 F)
2011
34.4 C (93.9 F)
2012
38.3 C (100.9 F)
Coldest night (TNn)
The coldest night of the year at Richardson Gr Sp, 1961 to 2012. The record is -9.4 C (15.1 F) in 1990, marked on the chart; the median year is -3.0 C (26.5 F).
Coldest night (TNn) at Richardson Gr Sp by year
Year
Coldest night (TNn)
1961
-3.3 C (26.1 F)
1962
-6.1 C (21.0 F)
1963
-6.1 C (21.0 F)
1964
-2.2 C (28.0 F)
1965
-5.6 C (21.9 F)
1966
-2.2 C (28.0 F)
1967
-4.4 C (24.1 F)
1968
-3.3 C (26.1 F)
1969
-2.2 C (28.0 F)
1970
-2.2 C (28.0 F)
1971
-3.3 C (26.1 F)
1972
-8.3 C (17.1 F)
1973
-2.8 C (27.0 F)
1974
-3.3 C (26.1 F)
1975
-3.9 C (25.0 F)
1976
-5.6 C (21.9 F)
1977
-3.9 C (25.0 F)
1978
-5.6 C (21.9 F)
1979
-5.6 C (21.9 F)
1980
-3.9 C (25.0 F)
1981
1.1 C (34.0 F)
1982
-2.8 C (27.0 F)
1983
-2.2 C (28.0 F)
1984
-1.7 C (28.9 F)
1985
-2.8 C (27.0 F)
1986
-1.1 C (30.0 F)
1987
-4.4 C (24.1 F)
1988
-2.2 C (28.0 F)
1989
-6.7 C (19.9 F)
1990
-9.4 C (15.1 F)
1991
-5.6 C (21.9 F)
1992
-1.7 C (28.9 F)
1993
-3.3 C (26.1 F)
1994
-1.7 C (28.9 F)
1995
-1.7 C (28.9 F)
1996
-1.7 C (28.9 F)
1997
-4.4 C (24.1 F)
1998
-5.6 C (21.9 F)
1999
-1.1 C (30.0 F)
2000
0.0 C (32.0 F)
2001
-2.2 C (28.0 F)
2002
-2.8 C (27.0 F)
2003
-4.4 C (24.1 F)
2004
-5.0 C (23.0 F)
2005
0.6 C (33.1 F)
2006
-2.2 C (28.0 F)
2007
-5.6 C (21.9 F)
2008
-1.1 C (30.0 F)
2009
-5.0 C (23.0 F)
2010
-1.7 C (28.9 F)
2011
-1.1 C (30.0 F)
2012
6.1 C (43.0 F)
Wettest day (Rx1day)
The wettest day of the year at Richardson Gr Sp, 1961 to 2012. The record is 287.0 mm (11.3 in) in 1964, marked on the chart; the median year is 115.4 mm (4.5 in).
Wettest day (Rx1day) at Richardson Gr Sp by year
Year
Wettest day (Rx1day)
1961
58.4 mm (2.3 in)
1962
147.8 mm (5.8 in)
1963
133.6 mm (5.3 in)
1964
287.0 mm (11.3 in)
1965
103.6 mm (4.1 in)
1966
100.3 mm (3.9 in)
1967
86.6 mm (3.4 in)
1968
129.0 mm (5.1 in)
1969
159.0 mm (6.3 in)
1970
119.4 mm (4.7 in)
1971
134.1 mm (5.3 in)
1972
115.6 mm (4.6 in)
1973
113.0 mm (4.4 in)
1974
200.7 mm (7.9 in)
1975
151.4 mm (6.0 in)
1976
101.6 mm (4.0 in)
1977
127.5 mm (5.0 in)
1978
97.8 mm (3.9 in)
1979
142.0 mm (5.6 in)
1980
98.3 mm (3.9 in)
1981
129.5 mm (5.1 in)
1982
105.7 mm (4.2 in)
1983
115.1 mm (4.5 in)
1984
139.4 mm (5.5 in)
1985
119.4 mm (4.7 in)
1986
144.8 mm (5.7 in)
1987
135.1 mm (5.3 in)
1988
105.2 mm (4.1 in)
1989
111.8 mm (4.4 in)
1990
109.7 mm (4.3 in)
1991
94.0 mm (3.7 in)
1992
96.8 mm (3.8 in)
1993
171.5 mm (6.8 in)
1994
72.9 mm (2.9 in)
1995
174.5 mm (6.9 in)
1996
152.4 mm (6.0 in)
1997
152.9 mm (6.0 in)
1998
119.4 mm (4.7 in)
1999
104.1 mm (4.1 in)
2000
96.5 mm (3.8 in)
2001
109.7 mm (4.3 in)
2002
133.9 mm (5.3 in)
2003
97.5 mm (3.8 in)
2004
104.1 mm (4.1 in)
2005
172.7 mm (6.8 in)
2006
70.1 mm (2.8 in)
2007
96.8 mm (3.8 in)
2008
188.5 mm (7.4 in)
2009
82.0 mm (3.2 in)
2010
88.9 mm (3.5 in)
2011
129.5 mm (5.1 in)
2012
0.0 mm (0.00 in)
Wettest five days (Rx5day)
The wettest five days of the year at Richardson Gr Sp, 1961 to 2012. The record is 696.5 mm (27.4 in) in 1964, marked on the chart; the median year is 260.9 mm (10.3 in).
Wettest five days (Rx5day) at Richardson Gr Sp by year
Year
Wettest five days (Rx5day)
1961
158.9 mm (6.3 in)
1962
311.1 mm (12.2 in)
1963
283.9 mm (11.2 in)
1964
696.5 mm (27.4 in)
1965
256.8 mm (10.1 in)
1966
264.9 mm (10.4 in)
1967
222.8 mm (8.8 in)
1968
299.1 mm (11.8 in)
1969
295.9 mm (11.6 in)
1970
336.1 mm (13.2 in)
1971
299.7 mm (11.8 in)
1972
224.3 mm (8.8 in)
1973
290.5 mm (11.4 in)
1974
478.4 mm (18.8 in)
1975
279.7 mm (11.0 in)
1976
247.7 mm (9.8 in)
1977
255.5 mm (10.1 in)
1978
249.5 mm (9.8 in)
1979
226.9 mm (8.9 in)
1980
258.3 mm (10.2 in)
1981
302.2 mm (11.9 in)
1982
283.8 mm (11.2 in)
1983
257.6 mm (10.1 in)
1984
305.2 mm (12.0 in)
1985
157.5 mm (6.2 in)
1986
480.1 mm (18.9 in)
1987
316.4 mm (12.5 in)
1988
229.7 mm (9.0 in)
1989
208.6 mm (8.2 in)
1990
236.7 mm (9.3 in)
1991
206.8 mm (8.1 in)
1992
235.2 mm (9.3 in)
1993
263.4 mm (10.4 in)
1994
183.3 mm (7.2 in)
1995
456.4 mm (18.0 in)
1996
320.8 mm (12.6 in)
1997
486.1 mm (19.1 in)
1998
275.1 mm (10.8 in)
1999
223.2 mm (8.8 in)
2000
186.8 mm (7.4 in)
2001
193.6 mm (7.6 in)
2002
457.5 mm (18.0 in)
2003
301.0 mm (11.9 in)
2004
230.3 mm (9.1 in)
2005
368.8 mm (14.5 in)
2006
368.8 mm (14.5 in)
2007
167.5 mm (6.6 in)
2008
268.4 mm (10.6 in)
2009
153.7 mm (6.1 in)
2010
208.7 mm (8.2 in)
2011
91.4 mm (3.6 in)
2012
0.0 mm (0.00 in)
Longest dry spell (CDD)
The longest dry spell of the year at Richardson Gr Sp, 1961 to 2012. The record is 162 days in 2002, marked on the chart; the median year is 81 days.
Longest dry spell (CDD) at Richardson Gr Sp by year
Year
Longest dry spell (CDD)
1961
11 days
1962
75 days
1963
87 days
1964
142 days
1965
56 days
1966
80 days
1967
105 days
1968
74 days
1969
90 days
1970
130 days
1971
65 days
1972
65 days
1973
116 days
1974
82 days
1975
53 days
1976
51 days
1977
89 days
1978
71 days
1979
62 days
1980
86 days
1981
107 days
1982
77 days
1983
48 days
1984
99 days
1985
62 days
1986
89 days
1987
123 days
1988
63 days
1989
53 days
1990
39 days
1991
56 days
1992
31 days
1993
74 days
1994
86 days
1995
67 days
1996
115 days
1997
50 days
1998
125 days
1999
140 days
2000
85 days
2001
55 days
2002
162 days
2003
121 days
2004
123 days
2005
117 days
2006
45 days
2007
98 days
2008
93 days
2009
101 days
2010
102 days
2011
5 days
2012
14 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
33 years with a frost
Across 33 years with a frost, the median last spring frost at Richardson Gr Sp falls on 13 March and the median first autumn frost on 27 November, which leaves a median of 259 days between them.
Fitted over all years, the growing season changes by -14.4 days per decade at this station.
Frost dates and growing season at Richardson Gr Sp
Measure
Median, all years
Earliest period
Recent period (1966 to 2009)
Recent against earliest
Fitted trend
Last spring frost
13 March
n/a
13 March
n/a
+5.8 days per decade
First autumn frost
27 November
n/a
27 November
n/a
-8.6 days per decade
Growing days
259 days
n/a
256 days
n/a
-14.4 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
44 years, 1962 to 2009
A day with at least 117.3 mm (4.6 in) of rain is expected about once in 2 years. A day with at least 256.2 mm (10.1 in) of rain is expected about once in 100 years.
Rainfall return levels at Richardson Gr 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
117.3 mm (4.6 in)
5 years
146.4 mm (5.8 in)
10 years
168.5 mm (6.6 in)
25 years
200.3 mm (7.9 in)
50 years
226.9 mm (8.9 in)
Longer than the 44 years of record
100 years
256.2 mm (10.1 in)
Longer than the 44 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, 44 years of values from 1962 to 2009.
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: 287.0 mm (11.3 in) in 1964; 200.7 mm (7.9 in) in 1974; 174.5 mm (6.9 in) in 1995.
Download the Data
Data for Richardson Gr Sp standing records by year: CSV or JSON. Field meanings are on the data page.
Data for Richardson Gr 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 2026-10-13 (13 October 2026). Records are computed by this site and are not official.