Record envelope, standing records and threshold days for Boswell 1 S (USC00340980), Oklahoma, United States, with 59 years of record.
Key Facts for Boswell 1 S
Boswell 1 S (USC00340980) is a weather station in Oklahoma, United States at 34.02 latitude and -95.87 longitude, 168 m (550 ft) above sea level.
The station reports from 1941 to 1999, 59 years of record.
1,464 records set at Boswell 1 S still stand.
Records are tracked for tmax, tmin, prcp, snow, snwd: an element needs 30 years of data to be eligible.
Boswell 1 S set a daily record high maximum temperature of 40.0 C (104.0 F) on 9 August 1999.
About the Station
Location: Oklahoma, United States, 34.02 latitude, -95.87 longitude.
Elevation: 168 m (550 ft).
Period of record: 1941 to 1999, 59 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 Boswell 1 S. 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 Boswell 1 S, 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)
-17.2 C (1.0 F)
n/a
n/a
Feb
33.3 C (91.9 F)
-16.7 C (1.9 F)
n/a
n/a
Mar
33.3 C (91.9 F)
-12.2 C (10.0 F)
n/a
n/a
Apr
33.9 C (93.0 F)
-3.9 C (25.0 F)
n/a
n/a
May
35.0 C (95.0 F)
3.3 C (37.9 F)
n/a
n/a
Jun
37.8 C (100.0 F)
8.3 C (46.9 F)
n/a
n/a
Jul
42.2 C (108.0 F)
10.0 C (50.0 F)
n/a
n/a
Aug
42.2 C (108.0 F)
10.0 C (50.0 F)
n/a
n/a
Sep
42.8 C (109.0 F)
3.3 C (37.9 F)
n/a
n/a
Oct
36.1 C (97.0 F)
-6.7 C (19.9 F)
n/a
n/a
Nov
31.7 C (89.1 F)
-11.1 C (12.0 F)
n/a
n/a
Dec
26.7 C (80.1 F)
-19.4 C (-2.9 F)
n/a
n/a
Which Years Hold Standing Records
1,464 standing records
Year with most
1,464 records at Boswell 1 S still stand. 1989 holds the most, with 62.
Standing records at Boswell 1 S by the year they were set
Year set
Standing records
1959
33
1960
37
1961
45
1962
37
1963
53
1964
32
1965
38
1966
43
1967
49
1968
25
1969
25
1970
47
1971
34
1972
44
1973
22
1974
46
1975
38
1976
47
1977
41
1978
58
1979
19
1980
3
1981
23
1982
30
1983
44
1984
32
1985
30
1986
31
1987
17
1988
40
1989
62
1990
41
1991
39
1992
30
1993
27
1994
34
1995
41
1996
29
1997
39
1998
47
1999
12
All-Time Record Progression
4 new records
4 all-time records were set at Boswell 1 S between 3 June 1994 and 5 September 1998. Each dot is a new record.
When Boswell 1 S set new all-time records
Date
Kind
Detail
1994-06-03
Record high minimum temperature
Record high minimum temperature 28.9 C (84.0 F)
1994-06-14
Record high minimum temperature
Record high minimum temperature 29.4 C (84.9 F)
1994-07-01
Record high minimum temperature
Record high minimum temperature 32.2 C (90.0 F)
1998-09-05
Record high maximum temperature
Record high maximum temperature 42.8 C (109.0 F)
Wettest Day of Each Month
Sep: 243.3 mm (9.6 in)
The wettest day on record for each calendar month at Boswell 1 S. The most was 243.3 mm (9.6 in) on 22 September 1957.
Record daily precipitation for each month at Boswell 1 S
Month
Record daily precipitation (mm)
Date
Jan
109.2 mm (4.3 in)
25 January 1949
Feb
105.4 mm (4.1 in)
12 February 1950
Mar
178.6 mm (7.0 in)
27 March 1977
Apr
100.1 mm (3.9 in)
6 April 1953
May
170.2 mm (6.7 in)
13 May 1982
Jun
116.1 mm (4.6 in)
17 June 1964
Jul
95.3 mm (3.8 in)
16 July 1959
Aug
88.9 mm (3.5 in)
17 August 1950
Sep
243.3 mm (9.6 in)
22 September 1957
Oct
200.7 mm (7.9 in)
25 October 1991
Nov
111.8 mm (4.4 in)
2 November 1982
Dec
80.5 mm (3.2 in)
21 December 1997
Period of Record Coverage
1959 to 1999
Complete yearUnder 90 percent of days
41 years of record at Boswell 1 S, 1959 to 1999. 13 years have data for under 90 percent of days and are left out of rankings: 1959, 1966, 1968, 1978, 1979, 1980, 1982, 1983 and others.
Cooler than the station meanWarmer than the station mean
One stripe for each of 24 complete years at Boswell 1 S, 1960 to 1997. Blue stripes are years cooler than the station's own mean of 17.0 C (62.6 F); red stripes are warmer. The coolest year was 1976, at 16.2 C (61.1 F), and the warmest was 1990, at 18.8 C (65.8 F). The strongest colour marks a difference of 1.8 C (3.2 F).
Annual mean temperature at Boswell 1 S as warming stripes, 1960 to 1997
Year
Annual mean temperature
Difference from the station mean
1960
16.3 C
-0.69 C
1961
16.3 C
-0.71 C
1962
16.8 C
-0.17 C
1963
17.1 C
+0.15 C
1964
16.7 C
-0.25 C
1967
17.1 C
+0.10 C
1969
17.0 C
0.00 C
1971
16.9 C
-0.05 C
1972
16.8 C
-0.23 C
1973
16.6 C
-0.42 C
1974
16.7 C
-0.33 C
1975
16.6 C
-0.40 C
1976
16.2 C
-0.81 C
1977
17.7 C
+0.70 C
1981
17.4 C
+0.40 C
1985
16.8 C
-0.20 C
1986
17.6 C
+0.60 C
1988
17.0 C
+0.05 C
1989
17.0 C
-0.02 C
1990
18.8 C
+1.76 C
1991
18.2 C
+1.16 C
1992
17.3 C
+0.32 C
1993
16.7 C
-0.29 C
1997
16.3 C
-0.67 C
This station does not have enough complete years (30 are needed) to fit a temperature trend.
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
1941 to 1999
Yearly extremes at Boswell 1 S: the record and the median year
Measure
Record
Year of the record
Median year
Years with a value
Hottest day (TXx)
42.8 C (109.0 F)
1998
38.9 C (102.0 F)
41
Coldest night (TNn)
-19.4 C (-2.9 F)
1989
-12.8 C (9.0 F)
41
Wettest day (Rx1day)
243.3 mm (9.6 in)
1957
80.4 mm (3.2 in)
56
Wettest five days (Rx5day)
341.1 mm (13.4 in)
1991
134.6 mm (5.3 in)
56
Longest dry spell (CDD)
46 days
1975
28 days
56
Hottest day (TXx)
The hottest day of the year at Boswell 1 S, 1941 to 1999. The record is 42.8 C (109.0 F) in 1998, marked on the chart; the median year is 38.9 C (102.0 F).
Hottest day (TXx) at Boswell 1 S by year
Year
Hottest day (TXx)
1941
n/a
1942
n/a
1943
n/a
1947
n/a
1948
n/a
1949
n/a
1950
n/a
1951
n/a
1952
n/a
1953
n/a
1954
n/a
1955
n/a
1956
n/a
1957
n/a
1958
n/a
1959
35.0 C (95.0 F)
1960
38.3 C (100.9 F)
1961
36.7 C (98.1 F)
1962
38.9 C (102.0 F)
1963
39.4 C (102.9 F)
1964
42.2 C (108.0 F)
1965
38.3 C (100.9 F)
1966
41.1 C (106.0 F)
1967
37.8 C (100.0 F)
1968
34.4 C (93.9 F)
1969
38.9 C (102.0 F)
1970
40.6 C (105.1 F)
1971
40.0 C (104.0 F)
1972
39.4 C (102.9 F)
1973
37.2 C (99.0 F)
1974
41.1 C (106.0 F)
1975
37.8 C (100.0 F)
1976
39.4 C (102.9 F)
1977
39.4 C (102.9 F)
1978
40.0 C (104.0 F)
1979
36.7 C (98.1 F)
1980
27.2 C (81.0 F)
1981
38.3 C (100.9 F)
1982
37.2 C (99.0 F)
1983
37.8 C (100.0 F)
1984
40.6 C (105.1 F)
1985
41.1 C (106.0 F)
1986
42.2 C (108.0 F)
1987
38.3 C (100.9 F)
1988
38.9 C (102.0 F)
1989
38.3 C (100.9 F)
1990
41.1 C (106.0 F)
1991
36.7 C (98.1 F)
1992
35.6 C (96.1 F)
1993
40.6 C (105.1 F)
1994
36.7 C (98.1 F)
1995
40.0 C (104.0 F)
1996
33.3 C (91.9 F)
1997
38.3 C (100.9 F)
1998
42.8 C (109.0 F)
1999
40.0 C (104.0 F)
Coldest night (TNn)
The coldest night of the year at Boswell 1 S, 1941 to 1999. The record is -19.4 C (-2.9 F) in 1989, marked on the chart; the median year is -12.8 C (9.0 F).
Coldest night (TNn) at Boswell 1 S by year
Year
Coldest night (TNn)
1941
n/a
1942
n/a
1943
n/a
1947
n/a
1948
n/a
1949
n/a
1950
n/a
1951
n/a
1952
n/a
1953
n/a
1954
n/a
1955
n/a
1956
n/a
1957
n/a
1958
n/a
1959
-9.4 C (15.1 F)
1960
-10.0 C (14.0 F)
1961
-11.1 C (12.0 F)
1962
-16.7 C (1.9 F)
1963
-16.7 C (1.9 F)
1964
-17.2 C (1.0 F)
1965
-12.2 C (10.0 F)
1966
-16.1 C (3.0 F)
1967
-11.1 C (12.0 F)
1968
-11.7 C (10.9 F)
1969
-11.1 C (12.0 F)
1970
-13.3 C (8.1 F)
1971
-12.8 C (9.0 F)
1972
-12.8 C (9.0 F)
1973
-10.0 C (14.0 F)
1974
-11.7 C (10.9 F)
1975
-11.7 C (10.9 F)
1976
-15.6 C (3.9 F)
1977
-15.6 C (3.9 F)
1978
-15.6 C (3.9 F)
1979
-14.4 C (6.1 F)
1980
-10.0 C (14.0 F)
1981
-15.0 C (5.0 F)
1982
-16.7 C (1.9 F)
1983
-17.2 C (1.0 F)
1984
-14.4 C (6.1 F)
1985
-16.7 C (1.9 F)
1986
-10.6 C (12.9 F)
1987
-6.7 C (19.9 F)
1988
-16.7 C (1.9 F)
1989
-19.4 C (-2.9 F)
1990
-12.8 C (9.0 F)
1991
-6.7 C (19.9 F)
1992
-11.7 C (10.9 F)
1993
-10.0 C (14.0 F)
1994
-10.6 C (12.9 F)
1995
-12.8 C (9.0 F)
1996
-16.7 C (1.9 F)
1997
-11.7 C (10.9 F)
1998
-8.9 C (16.0 F)
1999
-10.6 C (12.9 F)
Wettest day (Rx1day)
The wettest day of the year at Boswell 1 S, 1941 to 1999. The record is 243.3 mm (9.6 in) in 1957, marked on the chart; the median year is 80.4 mm (3.2 in).
Wettest day (Rx1day) at Boswell 1 S by year
Year
Wettest day (Rx1day)
1941
43.2 mm (1.7 in)
1942
79.5 mm (3.1 in)
1943
79.5 mm (3.1 in)
1947
59.7 mm (2.4 in)
1948
89.4 mm (3.5 in)
1949
109.2 mm (4.3 in)
1950
105.4 mm (4.1 in)
1951
84.3 mm (3.3 in)
1952
77.2 mm (3.0 in)
1953
100.1 mm (3.9 in)
1954
154.9 mm (6.1 in)
1955
79.8 mm (3.1 in)
1956
40.6 mm (1.6 in)
1957
243.3 mm (9.6 in)
1958
79.8 mm (3.1 in)
1959
95.3 mm (3.8 in)
1960
67.3 mm (2.6 in)
1961
100.8 mm (4.0 in)
1962
88.4 mm (3.5 in)
1963
74.2 mm (2.9 in)
1964
116.1 mm (4.6 in)
1965
147.3 mm (5.8 in)
1966
80.3 mm (3.2 in)
1967
108.0 mm (4.3 in)
1968
94.7 mm (3.7 in)
1969
71.1 mm (2.8 in)
1970
56.6 mm (2.2 in)
1971
43.2 mm (1.7 in)
1972
109.2 mm (4.3 in)
1973
68.6 mm (2.7 in)
1974
133.4 mm (5.3 in)
1975
88.9 mm (3.5 in)
1976
51.6 mm (2.0 in)
1977
178.6 mm (7.0 in)
1978
66.0 mm (2.6 in)
1979
66.0 mm (2.6 in)
1980
78.7 mm (3.1 in)
1981
77.5 mm (3.1 in)
1982
170.2 mm (6.7 in)
1983
51.1 mm (2.0 in)
1984
67.3 mm (2.6 in)
1985
81.3 mm (3.2 in)
1986
87.6 mm (3.4 in)
1987
62.2 mm (2.4 in)
1988
53.6 mm (2.1 in)
1989
59.9 mm (2.4 in)
1990
133.6 mm (5.3 in)
1991
200.7 mm (7.9 in)
1992
67.6 mm (2.7 in)
1993
157.5 mm (6.2 in)
1994
98.6 mm (3.9 in)
1995
66.3 mm (2.6 in)
1996
101.6 mm (4.0 in)
1997
80.5 mm (3.2 in)
1998
95.3 mm (3.8 in)
1999
60.2 mm (2.4 in)
Wettest five days (Rx5day)
The wettest five days of the year at Boswell 1 S, 1941 to 1999. The record is 341.1 mm (13.4 in) in 1991, marked on the chart; the median year is 134.6 mm (5.3 in).
Wettest five days (Rx5day) at Boswell 1 S by year
Year
Wettest five days (Rx5day)
1941
61.0 mm (2.4 in)
1942
167.0 mm (6.6 in)
1943
91.7 mm (3.6 in)
1947
74.5 mm (2.9 in)
1948
99.1 mm (3.9 in)
1949
220.4 mm (8.7 in)
1950
161.5 mm (6.4 in)
1951
148.1 mm (5.8 in)
1952
133.8 mm (5.3 in)
1953
118.6 mm (4.7 in)
1954
241.0 mm (9.5 in)
1955
182.2 mm (7.2 in)
1956
82.6 mm (3.3 in)
1957
245.3 mm (9.7 in)
1958
147.1 mm (5.8 in)
1959
134.5 mm (5.3 in)
1960
112.5 mm (4.4 in)
1961
111.7 mm (4.4 in)
1962
180.3 mm (7.1 in)
1963
114.6 mm (4.5 in)
1964
119.4 mm (4.7 in)
1965
166.1 mm (6.5 in)
1966
134.7 mm (5.3 in)
1967
148.3 mm (5.8 in)
1968
120.6 mm (4.7 in)
1969
99.1 mm (3.9 in)
1970
73.9 mm (2.9 in)
1971
108.3 mm (4.3 in)
1972
227.8 mm (9.0 in)
1973
146.0 mm (5.7 in)
1974
170.2 mm (6.7 in)
1975
153.7 mm (6.1 in)
1976
75.4 mm (3.0 in)
1977
213.1 mm (8.4 in)
1978
166.3 mm (6.5 in)
1979
137.1 mm (5.4 in)
1980
134.9 mm (5.3 in)
1981
169.9 mm (6.7 in)
1982
193.8 mm (7.6 in)
1983
94.0 mm (3.7 in)
1984
109.7 mm (4.3 in)
1985
148.1 mm (5.8 in)
1986
145.8 mm (5.7 in)
1987
116.6 mm (4.6 in)
1988
58.9 mm (2.3 in)
1989
109.7 mm (4.3 in)
1990
188.7 mm (7.4 in)
1991
341.1 mm (13.4 in)
1992
124.5 mm (4.9 in)
1993
224.3 mm (8.8 in)
1994
103.4 mm (4.1 in)
1995
124.7 mm (4.9 in)
1996
127.0 mm (5.0 in)
1997
124.5 mm (4.9 in)
1998
158.3 mm (6.2 in)
1999
109.7 mm (4.3 in)
Longest dry spell (CDD)
The longest dry spell of the year at Boswell 1 S, 1941 to 1999. The record is 46 days in 1975, marked on the chart; the median year is 28 days.
Longest dry spell (CDD) at Boswell 1 S by year
Year
Longest dry spell (CDD)
1941
14 days
1942
28 days
1943
37 days
1947
18 days
1948
38 days
1949
26 days
1950
34 days
1951
24 days
1952
34 days
1953
23 days
1954
37 days
1955
39 days
1956
31 days
1957
28 days
1958
22 days
1959
29 days
1960
19 days
1961
21 days
1962
24 days
1963
29 days
1964
39 days
1965
26 days
1966
18 days
1967
29 days
1968
19 days
1969
37 days
1970
31 days
1971
29 days
1972
27 days
1973
22 days
1974
22 days
1975
46 days
1976
24 days
1977
39 days
1978
45 days
1979
16 days
1980
22 days
1981
22 days
1982
22 days
1983
33 days
1984
20 days
1985
20 days
1986
36 days
1987
29 days
1988
30 days
1989
22 days
1990
16 days
1991
30 days
1992
26 days
1993
37 days
1994
12 days
1995
26 days
1996
44 days
1997
22 days
1998
31 days
1999
30 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
24 years with a frost
Across 24 years with a frost, the median last spring frost at Boswell 1 S falls on 1 April and the median first autumn frost on 8 November, which leaves a median of 224 days between them.
Frost dates and growing season at Boswell 1 S
Measure
Median, all years
Earliest period
Recent period (1960 to 1997)
Recent against earliest
Fitted trend
Last spring frost
1 April
n/a
1 April
n/a
n/a
First autumn frost
8 November
n/a
8 November
n/a
n/a
Growing days
224 days
n/a
224 days
n/a
n/a
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
47 years, 1942 to 1998
A day with at least 86.2 mm (3.4 in) of rain is expected about once in 2 years. A day with at least 263.6 mm (10.4 in) of rain is expected about once in 100 years.
Rainfall return levels at Boswell 1 S: the daily rain expected about once in a given number of years
Expected about once in
A day with at least
Note
2 years
86.2 mm (3.4 in)
5 years
120.7 mm (4.8 in)
10 years
148.0 mm (5.8 in)
25 years
188.5 mm (7.4 in)
50 years
223.7 mm (8.8 in)
Longer than the 47 years of record
100 years
263.6 mm (10.4 in)
Longer than the 47 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, 47 years of values from 1942 to 1998.
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: 243.3 mm (9.6 in) in 1957; 200.7 mm (7.9 in) in 1991; 178.6 mm (7.0 in) in 1977.
Download the Data
Data for Boswell 1 S standing records by year: CSV or JSON. Field meanings are on the data page.
Data for Boswell 1 S 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.