Record envelope, standing records and threshold days for Sweetgrass (USC00248093), Montana, United States, with 84 years of record.
Key Facts for Sweetgrass
Sweetgrass (USC00248093) is a weather station in Montana, United States at 49.00 latitude and -111.96 longitude, 1,070 m (3,510 ft) above sea level.
The station reports from 1925 to 2008, 84 years of record.
1,464 records set at Sweetgrass still stand.
Records are tracked for tmax, tmin, prcp, snow, snwd: an element needs 30 years of data to be eligible.
Sweetgrass set a daily record low minimum temperature of -33.9 C (-29.0 F) on 29 January 2008.
About the Station
Location: Montana, United States, 49.00 latitude, -111.96 longitude.
Elevation: 1,070 m (3,510 ft).
Period of record: 1925 to 2008, 84 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 Sweetgrass. 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 Sweetgrass, with 2026 drawn through them
Month
Highest record high
Lowest record low
2026 highest maximum
2026 lowest minimum
Jan
17.8 C (64.0 F)
-39.4 C (-38.9 F)
n/a
n/a
Feb
21.1 C (70.0 F)
-37.2 C (-35.0 F)
n/a
n/a
Mar
22.2 C (72.0 F)
-33.9 C (-29.0 F)
n/a
n/a
Apr
28.9 C (84.0 F)
-21.7 C (-7.1 F)
n/a
n/a
May
32.8 C (91.0 F)
-10.6 C (12.9 F)
n/a
n/a
Jun
35.6 C (96.1 F)
-2.2 C (28.0 F)
n/a
n/a
Jul
40.6 C (105.1 F)
-1.1 C (30.0 F)
n/a
n/a
Aug
40.6 C (105.1 F)
-1.1 C (30.0 F)
n/a
n/a
Sep
35.0 C (95.0 F)
-11.1 C (12.0 F)
n/a
n/a
Oct
31.1 C (88.0 F)
-24.4 C (-11.9 F)
n/a
n/a
Nov
23.3 C (73.9 F)
-32.2 C (-26.0 F)
n/a
n/a
Dec
19.4 C (66.9 F)
-42.2 C (-44.0 F)
n/a
n/a
Which Years Hold Standing Records
1,464 standing records
Year with most
1,464 records at Sweetgrass still stand. 1962 holds the most, with 52.
Standing records at Sweetgrass by the year they were set
Year set
Standing records
1956
19
1957
40
1958
32
1959
27
1960
33
1961
16
1962
52
1963
30
1964
23
1965
52
1966
29
1967
47
1968
28
1969
50
1970
20
1971
25
1972
39
1973
30
1974
22
1975
29
1976
22
1977
22
1978
15
1979
23
1980
30
1981
34
1982
29
1983
23
1984
32
1985
46
1986
23
1987
33
1988
30
1989
19
1990
32
1991
32
1992
43
1993
23
1994
23
1995
14
1996
30
1997
20
1998
21
1999
29
2000
24
2001
15
2002
40
2003
19
2005
22
2006
24
2007
28
2008
1
All-Time Record Progression
1 new records
1 all-time records were set at Sweetgrass between 2 February 1989 and 2 February 1989. Each dot is a new record.
When Sweetgrass set new all-time records
Date
Kind
Detail
1989-02-02
Record low maximum temperature
Record low maximum temperature -30.6 C (-23.1 F)
Wettest Day of Each Month
Aug: 89.2 mm (3.5 in)
The wettest day on record for each calendar month at Sweetgrass. The most was 89.2 mm (3.5 in) on 23 August 1978.
Record daily precipitation for each month at Sweetgrass
Month
Record daily precipitation (mm)
Date
Jan
10.2 mm (0.4 in)
24 January 1959
Feb
11.4 mm (0.4 in)
26 February 1958
Mar
30.5 mm (1.2 in)
13 March 1990
Apr
82.6 mm (3.3 in)
20 April 1967
May
52.1 mm (2.1 in)
3 May 1964
Jun
81.3 mm (3.2 in)
9 June 2002
Jul
58.4 mm (2.3 in)
25 July 1993
Aug
89.2 mm (3.5 in)
23 August 1978
Sep
48.3 mm (1.9 in)
11 September 1988
Oct
32.0 mm (1.3 in)
12 October 1994
Nov
63.5 mm (2.5 in)
23 November 1990
Dec
19.1 mm (0.8 in)
14 December 1988
Period of Record Coverage
1956 to 2008
Complete yearUnder 90 percent of days
52 years of record at Sweetgrass, 1956 to 2008. 20 years have data for under 90 percent of days and are left out of rankings: 1956, 1959, 1984, 1986, 1987, 1989, 1990, 1991 and others.
Cooler than the station meanWarmer than the station mean
One stripe for each of 35 complete years at Sweetgrass, 1957 to 2007. Blue stripes are years cooler than the station's own mean of 6.3 C (43.3 F); red stripes are warmer. The coolest year was 1982, at 4.4 C (40.0 F), and the warmest was 1981, at 8.0 C (46.4 F). The strongest colour marks a difference of 1.9 C (3.4 F).
Annual mean temperature at Sweetgrass as warming stripes, 1957 to 2007
Year
Annual mean temperature
Difference from the station mean
1957
5.7 C
-0.63 C
1958
6.5 C
+0.20 C
1960
5.8 C
-0.48 C
1961
6.6 C
+0.28 C
1962
6.0 C
-0.30 C
1963
7.0 C
+0.68 C
1964
5.3 C
-1.03 C
1965
4.5 C
-1.80 C
1966
5.5 C
-0.79 C
1967
6.3 C
+0.02 C
1968
5.8 C
-0.50 C
1969
5.2 C
-1.15 C
1971
5.6 C
-0.71 C
1973
6.7 C
+0.37 C
1974
7.1 C
+0.83 C
1975
4.9 C
-1.41 C
1976
7.7 C
+1.38 C
1977
6.5 C
+0.22 C
1978
4.6 C
-1.75 C
1979
5.8 C
-0.47 C
1980
6.2 C
-0.11 C
1981
8.0 C
+1.68 C
1982
4.4 C
-1.86 C
1983
6.6 C
+0.30 C
1985
5.2 C
-1.12 C
1988
7.9 C
+1.55 C
1989
6.1 C
-0.23 C
1990
6.7 C
+0.40 C
1991
7.1 C
+0.80 C
1992
7.5 C
+1.21 C
1997
6.6 C
+0.33 C
1998
7.5 C
+1.23 C
1999
8.0 C
+1.66 C
2006
7.2 C
+0.88 C
2007
6.7 C
+0.41 C
The annual mean temperature here has risen by 0.3 C (0.1 to 0.6) per decade over 1957 to 2007. In Fahrenheit: 0.6 F (0.2 to 1.0) per decade. The slope is a straight line fitted to 35 complete years; the brackets give its 95 percent interval.
Fitted temperature trends per decade at Sweetgrass
Measure
Per decade (C)
Per decade (F)
Period
Complete years
Reading
Annual mean temperature
0.3 C (0.1 to 0.6) per decade
0.6 F (0.2 to 1.0) per decade
1957 to 2007
35
Rise
Mean daily maximum
0.28 C (-0.03 to 0.58) per decade
0.5 F (-0.1 to 1.0) per decade
1957 to 2007
35
Not clearly different from zero
Mean daily minimum
0.4 C (0.2 to 0.6) per decade
0.7 F (0.3 to 1.0) per decade
1957 to 2007
35
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
1925 to 2008
Yearly extremes at Sweetgrass: the record and the median year
Measure
Record
Year of the record
Median year
Years with a value
Hottest day (TXx)
40.6 C (105.1 F)
1961
35.6 C (96.1 F)
52
Coldest night (TNn)
-42.2 C (-44.0 F)
1984
-32.7 C (-26.9 F)
52
Wettest day (Rx1day)
89.2 mm (3.5 in)
1978
36.8 mm (1.4 in)
61
Wettest five days (Rx5day)
232.9 mm (9.2 in)
2002
54.8 mm (2.2 in)
61
Longest dry spell (CDD)
104 days
1999
37 days
61
Hottest day (TXx)
The hottest day of the year at Sweetgrass, 1925 to 2008. The record is 40.6 C (105.1 F) in 1961, marked on the chart; the median year is 35.6 C (96.1 F).
Hottest day (TXx) at Sweetgrass by year
Year
Hottest day (TXx)
1925
n/a
1926
n/a
1927
n/a
1928
n/a
1929
n/a
1930
n/a
1931
n/a
1951
n/a
1952
n/a
1956
32.2 C (90.0 F)
1957
35.6 C (96.1 F)
1958
33.9 C (93.0 F)
1959
35.6 C (96.1 F)
1960
38.9 C (102.0 F)
1961
40.6 C (105.1 F)
1962
33.9 C (93.0 F)
1963
35.6 C (96.1 F)
1964
35.0 C (95.0 F)
1965
33.3 C (91.9 F)
1966
32.8 C (91.0 F)
1967
35.0 C (95.0 F)
1968
33.9 C (93.0 F)
1969
37.8 C (100.0 F)
1970
33.9 C (93.0 F)
1971
37.2 C (99.0 F)
1972
33.9 C (93.0 F)
1973
37.8 C (100.0 F)
1974
35.0 C (95.0 F)
1975
37.2 C (99.0 F)
1976
33.9 C (93.0 F)
1977
34.4 C (93.9 F)
1978
33.3 C (91.9 F)
1979
35.0 C (95.0 F)
1980
35.6 C (96.1 F)
1981
35.0 C (95.0 F)
1982
32.8 C (91.0 F)
1983
38.3 C (100.9 F)
1984
36.1 C (97.0 F)
1985
37.2 C (99.0 F)
1986
34.4 C (93.9 F)
1987
35.6 C (96.1 F)
1988
34.4 C (93.9 F)
1989
34.4 C (93.9 F)
1990
36.7 C (98.1 F)
1991
35.6 C (96.1 F)
1992
33.9 C (93.0 F)
1993
31.7 C (89.1 F)
1994
37.2 C (99.0 F)
1995
31.7 C (89.1 F)
1996
36.1 C (97.0 F)
1997
36.1 C (97.0 F)
1998
35.6 C (96.1 F)
1999
35.0 C (95.0 F)
2000
36.1 C (97.0 F)
2001
36.7 C (98.1 F)
2002
36.1 C (97.0 F)
2003
38.3 C (100.9 F)
2005
35.6 C (96.1 F)
2006
37.2 C (99.0 F)
2007
40.6 C (105.1 F)
2008
9.4 C (48.9 F)
Coldest night (TNn)
The coldest night of the year at Sweetgrass, 1925 to 2008. The record is -42.2 C (-44.0 F) in 1984, marked on the chart; the median year is -32.7 C (-26.9 F).
Coldest night (TNn) at Sweetgrass by year
Year
Coldest night (TNn)
1925
n/a
1926
n/a
1927
n/a
1928
n/a
1929
n/a
1930
n/a
1931
n/a
1951
n/a
1952
n/a
1956
-36.1 C (-33.0 F)
1957
-39.4 C (-38.9 F)
1958
-31.1 C (-24.0 F)
1959
-32.2 C (-26.0 F)
1960
-33.9 C (-29.0 F)
1961
-31.7 C (-25.1 F)
1962
-33.9 C (-29.0 F)
1963
-34.4 C (-29.9 F)
1964
-34.4 C (-29.9 F)
1965
-30.6 C (-23.1 F)
1966
-31.1 C (-24.0 F)
1967
-31.1 C (-24.0 F)
1968
-37.8 C (-36.0 F)
1969
-36.7 C (-34.1 F)
1970
-30.0 C (-22.0 F)
1971
-35.6 C (-32.1 F)
1972
-36.7 C (-34.1 F)
1973
-30.0 C (-22.0 F)
1974
-30.6 C (-23.1 F)
1975
-31.1 C (-24.0 F)
1976
-29.4 C (-20.9 F)
1977
-38.3 C (-36.9 F)
1978
-33.3 C (-27.9 F)
1979
-33.3 C (-27.9 F)
1980
-34.4 C (-29.9 F)
1981
-30.0 C (-22.0 F)
1982
-35.0 C (-31.0 F)
1983
-40.0 C (-40.0 F)
1984
-42.2 C (-44.0 F)
1985
-36.1 C (-33.0 F)
1986
-33.9 C (-29.0 F)
1987
-26.1 C (-15.0 F)
1988
-31.7 C (-25.1 F)
1989
-36.1 C (-33.0 F)
1990
-38.9 C (-38.0 F)
1991
-31.7 C (-25.1 F)
1992
-39.4 C (-38.9 F)
1993
-31.1 C (-24.0 F)
1994
-37.2 C (-35.0 F)
1995
-31.7 C (-25.1 F)
1996
-36.7 C (-34.1 F)
1997
-37.2 C (-35.0 F)
1998
-32.2 C (-26.0 F)
1999
-25.6 C (-14.1 F)
2000
-32.2 C (-26.0 F)
2001
-25.0 C (-13.0 F)
2002
-30.6 C (-23.1 F)
2003
-30.0 C (-22.0 F)
2005
-23.9 C (-11.0 F)
2006
-32.2 C (-26.0 F)
2007
-26.1 C (-15.0 F)
2008
-33.9 C (-29.0 F)
Wettest day (Rx1day)
The wettest day of the year at Sweetgrass, 1925 to 2008. The record is 89.2 mm (3.5 in) in 1978, marked on the chart; the median year is 36.8 mm (1.4 in).
Wettest day (Rx1day) at Sweetgrass by year
Year
Wettest day (Rx1day)
1925
7.6 mm (0.30 in)
1926
31.8 mm (1.3 in)
1927
12.7 mm (0.5 in)
1928
2.5 mm (0.10 in)
1929
38.1 mm (1.5 in)
1930
32.5 mm (1.3 in)
1931
2.5 mm (0.10 in)
1951
80.5 mm (3.2 in)
1952
49.0 mm (1.9 in)
1956
14.0 mm (0.6 in)
1957
25.4 mm (1.0 in)
1958
30.0 mm (1.2 in)
1959
20.3 mm (0.8 in)
1960
61.7 mm (2.4 in)
1961
27.4 mm (1.1 in)
1962
22.4 mm (0.9 in)
1963
50.8 mm (2.0 in)
1964
63.8 mm (2.5 in)
1965
41.1 mm (1.6 in)
1966
58.4 mm (2.3 in)
1967
82.6 mm (3.3 in)
1968
38.1 mm (1.5 in)
1969
27.4 mm (1.1 in)
1970
62.0 mm (2.4 in)
1971
61.7 mm (2.4 in)
1972
23.1 mm (0.9 in)
1973
35.8 mm (1.4 in)
1974
30.5 mm (1.2 in)
1975
42.9 mm (1.7 in)
1976
28.7 mm (1.1 in)
1977
22.9 mm (0.9 in)
1978
89.2 mm (3.5 in)
1979
27.9 mm (1.1 in)
1980
36.8 mm (1.4 in)
1981
48.3 mm (1.9 in)
1982
29.7 mm (1.2 in)
1983
22.9 mm (0.9 in)
1984
25.4 mm (1.0 in)
1985
41.7 mm (1.6 in)
1986
30.0 mm (1.2 in)
1987
27.9 mm (1.1 in)
1988
48.3 mm (1.9 in)
1989
48.5 mm (1.9 in)
1990
63.5 mm (2.5 in)
1991
58.4 mm (2.3 in)
1992
31.5 mm (1.2 in)
1993
58.4 mm (2.3 in)
1994
37.6 mm (1.5 in)
1995
57.9 mm (2.3 in)
1996
36.8 mm (1.4 in)
1997
41.7 mm (1.6 in)
1998
38.1 mm (1.5 in)
1999
53.3 mm (2.1 in)
2000
27.9 mm (1.1 in)
2001
38.9 mm (1.5 in)
2002
81.3 mm (3.2 in)
2003
20.1 mm (0.8 in)
2005
40.6 mm (1.6 in)
2006
31.8 mm (1.3 in)
2007
22.1 mm (0.9 in)
2008
5.1 mm (0.20 in)
Wettest five days (Rx5day)
The wettest five days of the year at Sweetgrass, 1925 to 2008. The record is 232.9 mm (9.2 in) in 2002, marked on the chart; the median year is 54.8 mm (2.2 in).
Wettest five days (Rx5day) at Sweetgrass by year
Year
Wettest five days (Rx5day)
1925
3.6 mm (0.14 in)
1926
43.7 mm (1.7 in)
1927
17.7 mm (0.7 in)
1928
2.5 mm (0.10 in)
1929
65.5 mm (2.6 in)
1930
54.9 mm (2.2 in)
1931
2.5 mm (0.10 in)
1951
113.1 mm (4.5 in)
1952
55.9 mm (2.2 in)
1956
18.8 mm (0.7 in)
1957
34.6 mm (1.4 in)
1958
36.9 mm (1.5 in)
1959
35.6 mm (1.4 in)
1960
72.6 mm (2.9 in)
1961
42.9 mm (1.7 in)
1962
25.2 mm (1.0 in)
1963
54.6 mm (2.1 in)
1964
150.4 mm (5.9 in)
1965
89.6 mm (3.5 in)
1966
78.4 mm (3.1 in)
1967
105.3 mm (4.1 in)
1968
48.3 mm (1.9 in)
1969
67.7 mm (2.7 in)
1970
72.9 mm (2.9 in)
1971
87.1 mm (3.4 in)
1972
49.6 mm (2.0 in)
1973
48.5 mm (1.9 in)
1974
59.5 mm (2.3 in)
1975
108.3 mm (4.3 in)
1976
47.5 mm (1.9 in)
1977
51.9 mm (2.0 in)
1978
100.4 mm (4.0 in)
1979
44.9 mm (1.8 in)
1980
77.7 mm (3.1 in)
1981
104.2 mm (4.1 in)
1982
104.4 mm (4.1 in)
1983
25.1 mm (1.0 in)
1984
33.0 mm (1.3 in)
1985
63.3 mm (2.5 in)
1986
36.1 mm (1.4 in)
1987
53.6 mm (2.1 in)
1988
48.3 mm (1.9 in)
1989
70.7 mm (2.8 in)
1990
76.2 mm (3.0 in)
1991
119.4 mm (4.7 in)
1992
62.3 mm (2.5 in)
1993
85.6 mm (3.4 in)
1994
51.4 mm (2.0 in)
1995
140.5 mm (5.5 in)
1996
69.8 mm (2.7 in)
1997
93.4 mm (3.7 in)
1998
54.8 mm (2.2 in)
1999
72.1 mm (2.8 in)
2000
42.4 mm (1.7 in)
2001
41.4 mm (1.6 in)
2002
232.9 mm (9.2 in)
2003
20.1 mm (0.8 in)
2005
92.1 mm (3.6 in)
2006
47.1 mm (1.9 in)
2007
33.3 mm (1.3 in)
2008
8.9 mm (0.35 in)
Longest dry spell (CDD)
The longest dry spell of the year at Sweetgrass, 1925 to 2008. The record is 104 days in 1999, marked on the chart; the median year is 37 days.
Longest dry spell (CDD) at Sweetgrass by year
Year
Longest dry spell (CDD)
1925
30 days
1926
28 days
1927
23 days
1928
32 days
1929
28 days
1930
33 days
1931
36 days
1951
19 days
1952
52 days
1956
43 days
1957
45 days
1958
30 days
1959
49 days
1960
29 days
1961
36 days
1962
33 days
1963
80 days
1964
30 days
1965
55 days
1966
50 days
1967
38 days
1968
79 days
1969
78 days
1970
35 days
1971
48 days
1972
33 days
1973
59 days
1974
78 days
1975
30 days
1976
78 days
1977
42 days
1978
48 days
1979
51 days
1980
33 days
1981
42 days
1982
42 days
1983
39 days
1984
46 days
1985
36 days
1986
29 days
1987
37 days
1988
36 days
1989
37 days
1990
37 days
1991
31 days
1992
52 days
1993
25 days
1994
32 days
1995
33 days
1996
30 days
1997
70 days
1998
36 days
1999
104 days
2000
45 days
2001
43 days
2002
63 days
2003
64 days
2005
29 days
2006
37 days
2007
40 days
2008
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
35 years with a frost
Across 35 years with a frost, the median last spring frost at Sweetgrass falls on 21 May and the median first autumn frost on 18 September, which leaves a median of 117 days between them.
Fitted over all years, the growing season changes by +0.1 days per decade at this station.
Frost dates and growing season at Sweetgrass
Measure
Median, all years
Earliest period
Recent period (1963 to 2007)
Recent against earliest
Fitted trend
Last spring frost
21 May
n/a
21 May
n/a
+0.1 days per decade
First autumn frost
18 September
n/a
18 September
n/a
+0.2 days per decade
Growing days
117 days
n/a
117 days
n/a
+0.1 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, 1930 to 2007
A day with at least 38.1 mm (1.5 in) of rain is expected about once in 2 years. A day with at least 105.9 mm (4.2 in) of rain is expected about once in 100 years.
Rainfall return levels at Sweetgrass: the daily rain expected about once in a given number of years
Expected about once in
A day with at least
Note
2 years
38.1 mm (1.5 in)
5 years
53.9 mm (2.1 in)
10 years
65.2 mm (2.6 in)
25 years
80.6 mm (3.2 in)
50 years
92.9 mm (3.7 in)
Longer than the 44 years of record
100 years
105.9 mm (4.2 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 1930 to 2007.
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: 89.2 mm (3.5 in) in 1978; 82.6 mm (3.3 in) in 1967; 81.3 mm (3.2 in) in 2002.
Download the Data
Data for Sweetgrass standing records by year: CSV or JSON. Field meanings are on the data page.
Data for Sweetgrass 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 2026-10-15 (15 October 2026). Records are computed by this site and are not official.