Koosharem Weather Records (USC00424764)

Record envelope, standing records and threshold days for Koosharem (USC00424764), Utah, United States, with 117 years of record.

Key Facts for Koosharem

Koosharem (USC00424764) is a weather station in Utah, United States at 38.51 latitude and -111.88 longitude, 2,112 m (6,930 ft) above sea level.
The station reports from 1893 to 2009, 117 years of record.
1,464 records set at Koosharem still stand.
Records are tracked for tmax, tmin, prcp, snow, snwd: an element needs 30 years of data to be eligible.
Koosharem tied a daily record low maximum temperature of 6.1 C (43.0 F) on 15 April 2009.

About the Station

Location: Utah, United States, 38.51 latitude, -111.88 longitude.
Elevation: 2,112 m (6,930 ft).
Period of record: 1893 to 2009, 117 years.
Eligible elements: tmax, tmin, prcp, snow, snwd.

Daily Record Envelope and 2026

0 days at or beyond a record

The band shows the record high and record low for each calendar day at Koosharem. 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 Koosharem, 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)	-33.3 C (-27.9 F)	n/a	n/a
Feb	20.6 C (69.1 F)	-31.1 C (-24.0 F)	n/a	n/a
Mar	25.0 C (77.0 F)	-25.0 C (-13.0 F)	n/a	n/a
Apr	26.1 C (79.0 F)	-17.8 C (0.0 F)	n/a	n/a
May	32.8 C (91.0 F)	-11.1 C (12.0 F)	n/a	n/a
Jun	35.6 C (96.1 F)	-7.8 C (18.0 F)	n/a	n/a
Jul	36.7 C (98.1 F)	-2.8 C (27.0 F)	n/a	n/a
Aug	36.7 C (98.1 F)	-3.3 C (26.1 F)	n/a	n/a
Sep	33.3 C (91.9 F)	-11.7 C (10.9 F)	n/a	n/a
Oct	32.2 C (90.0 F)	-21.1 C (-6.0 F)	n/a	n/a
Nov	25.6 C (78.1 F)	-27.2 C (-17.0 F)	n/a	n/a
Dec	17.2 C (63.0 F)	-35.6 C (-32.1 F)	n/a	n/a

Which Years Hold Standing Records

1,464 standing records

1,464 records at Koosharem still stand. 1955 holds the most, with 45.

Standing records at Koosharem by the year they were set
Year set	Standing records
1893	16
1894	25
1895	33
1896	16
1897	17
1919	9
1920	6
1921	24
1922	33
1923	15
1924	3
1925	11
1926	14
1927	28
1928	14
1929	4
1952	10
1953	13
1954	24
1955	45
1956	36
1957	20
1958	16
1959	24
1960	24
1961	17
1962	44
1963	35
1964	24
1965	25
1966	22
1967	18
1968	16
1969	23
1970	14
1971	34
1972	28
1973	13
1974	23
1975	31
1976	17
1977	23
1978	16
1979	21
1980	26
1981	27
1982	18
1983	5
1984	13
1985	18
1986	26
1987	18
1988	14
1989	27
1990	25
1991	10
1992	16
1993	7
1994	13
1995	18
1996	22
1997	21
1998	12
1999	13
2000	35
2001	16
2002	19
2003	26
2004	22
2005	13
2006	21
2007	19
2008	15
2009	5

All-Time Record Progression

8 new records

8 all-time records were set at Koosharem between 25 July 1987 and 2 June 2005. Each dot is a new record.

When Koosharem set new all-time records
Date	Kind	Detail
1987-07-25	Record high minimum temperature	Record high minimum temperature 17.2 C (63.0 F)
1990-12-22	Record low minimum temperature	Record low minimum temperature -35.0 C (-31.0 F)
1990-12-23	Record low minimum temperature	Record low minimum temperature -35.6 C (-32.1 F)
1993-02-20	Record snow depth	Record snow depth 53.3 cm (21.0 in)
2002-07-02	Record high minimum temperature	Record high minimum temperature 18.3 C (64.9 F)
2002-07-03	Record high minimum temperature	Record high minimum temperature 19.4 C (66.9 F)
2002-07-15	Record high minimum temperature	Record high minimum temperature 20.6 C (69.1 F)
2005-06-02	Record daily precipitation	Record daily precipitation 40.6 mm (1.6 in)

Wettest Day of Each Month

Jun: 40.6 mm (1.6 in)

The wettest day on record for each calendar month at Koosharem. The most was 40.6 mm (1.6 in) on 2 June 2005.

Record daily precipitation for each month at Koosharem
Month	Record daily precipitation (mm)	Date
Jan	24.1 mm (0.9 in)	19 January 1929
Feb	22.9 mm (0.9 in)	26 February 1928
Mar	20.3 mm (0.8 in)	20 March 1897
Apr	25.4 mm (1.0 in)	12 April 2002
May	38.1 mm (1.5 in)	10 May 1922
Jun	40.6 mm (1.6 in)	2 June 2005
Jul	39.6 mm (1.6 in)	25 July 2007
Aug	37.1 mm (1.5 in)	15 August 1984
Sep	33.8 mm (1.3 in)	22 September 1967
Oct	35.6 mm (1.4 in)	21 October 2004
Nov	31.0 mm (1.2 in)	2 November 1978
Dec	18.8 mm (0.7 in)	6 December 1955

Period of Record Coverage

1893 to 2009

74 years of record at Koosharem, 1893 to 2009. 33 years have data for under 90 percent of days and are left out of rankings: 1893, 1896, 1897, 1919, 1920, 1923, 1924, 1925 and others.

Days with data per year at Koosharem
Year	Days with data	Share of year	Complete
1893	226	62%	No
1894	357	98%	Yes
1895	358	98%	Yes
1896	275	75%	No
1897	151	41%	No
1919	75	21%	No
1920	156	43%	No
1921	335	92%	Yes
1922	343	94%	Yes
1923	157	43%	No
1924	89	24%	No
1925	189	52%	No
1926	346	95%	Yes
1927	345	95%	Yes
1928	362	99%	Yes
1929	23	6%	No
1952	170	46%	No
1953	361	99%	Yes
1954	348	95%	Yes
1955	349	96%	Yes
1956	335	92%	Yes
1957	360	99%	Yes
1958	362	99%	Yes
1959	359	98%	Yes
1960	365	100%	Yes
1961	334	92%	Yes
1962	361	99%	Yes
1963	334	92%	Yes
1964	331	90%	Yes
1965	361	99%	Yes
1966	364	100%	Yes
1967	363	99%	Yes
1968	306	84%	No
1969	363	99%	Yes
1970	364	100%	Yes
1971	365	100%	Yes
1972	354	97%	Yes
1973	335	92%	Yes
1974	363	99%	Yes
1975	354	97%	Yes
1976	360	98%	Yes
1977	363	99%	Yes
1978	363	99%	Yes
1979	363	99%	Yes
1980	366	100%	Yes
1981	341	93%	Yes
1982	336	92%	Yes
1983	350	96%	Yes
1984	338	92%	Yes
1985	340	93%	Yes
1986	294	81%	No
1987	272	75%	No
1988	293	80%	No
1989	299	82%	No
1990	321	88%	No
1991	311	85%	No
1992	318	87%	No
1993	315	86%	No
1994	281	77%	No
1995	309	85%	No
1996	297	81%	No
1997	303	83%	No
1998	259	71%	No
1999	235	64%	No
2000	290	79%	No
2001	297	81%	No
2002	281	77%	No
2003	310	85%	No
2004	261	71%	No
2005	212	58%	No
2006	361	99%	Yes
2007	350	96%	Yes
2008	253	69%	No
2009	90	25%	No

Latest Records

Latest records at Koosharem
Date	Station	Record	Value	Beat old record by	Old record stood	Significance
15 April 2009	Koosharem, US	daily low max (Tie)	6.1 C (43.0 F)	tie	40 years	5 of 100 (Routine)
10 April 2009	Koosharem, US	daily rain	10.4 mm (0.4 in)	5.3 mm (0.21 in)	19 years	20 of 100 (Routine)
4 April 2009	Koosharem, US	daily low max	-1.1 C (30.0 F)	2.8 C (5.0 F)	51 years	29 of 100 (Routine)
27 March 2009	Koosharem, US	daily low min	-15.6 C (3.9 F)	2.3 C (4.1 F)	34 years	24 of 100 (Routine)
9 March 2009	Koosharem, US	daily snowfall	2.5 cm (1.0 in)	1.2 cm (0.5 in)	51 years	20 of 100 (Routine)
2 March 2009	Koosharem, US	daily high max	18.9 C (66.0 F)	3.3 C (5.9 F)	83 years	39 of 100 (Notable)
22 February 2009	Koosharem, US	daily high min	1.7 C (35.1 F)	2.8 C (5.0 F)	89 years	40 of 100 (Notable)
24 January 2009	Koosharem, US	daily rain	13.2 mm (0.5 in)	5.6 mm (0.22 in)	59 years	20 of 100 (Routine)
24 January 2009	Koosharem, US	daily high min (Tie)	0.6 C (33.1 F)	tie	10 years	3 of 100 (Routine)
23 January 2009	Koosharem, US	daily high min	0.6 C (33.1 F)	2.8 C (5.0 F)	53 years	29 of 100 (Routine)
2 January 2009	Koosharem, US	daily snow depth	25.4 cm (10.0 in)	2.5 cm (1.0 in)	27 years	20 of 100 (Routine)
1 January 2009	Koosharem, US	daily snow depth	25.4 cm (10.0 in)	5.1 cm (2.0 in)	20 years	21 of 100 (Routine)
27 December 2008	Koosharem, US	daily snow depth	35.6 cm (14.0 in)	15.3 cm (6.0 in)	30 years	42 of 100 (Notable)
26 December 2008	Koosharem, US	daily snow depth	35.6 cm (14.0 in)	12.7 cm (5.0 in)	40 years	41 of 100 (Notable)
25 December 2008	Koosharem, US	daily snow depth	35.6 cm (14.0 in)	12.7 cm (5.0 in)	30 years	38 of 100 (Notable)
24 December 2008	Koosharem, US	daily snow depth	35.6 cm (14.0 in)	12.7 cm (5.0 in)	30 years	38 of 100 (Notable)
23 December 2008	Koosharem, US	daily snow depth	35.6 cm (14.0 in)	10.2 cm (4.0 in)	41 years	37 of 100 (Notable)
19 December 2008	Koosharem, US	daily snow depth (Tie)	30.5 cm (12.0 in)	tie	41 years	5 of 100 (Routine)
18 December 2008	Koosharem, US	daily snow depth	30.5 cm (12.0 in)	5.1 cm (2.0 in)	41 years	29 of 100 (Routine)
17 December 2008	Koosharem, US	daily snow depth (Tie)	20.3 cm (8.0 in)	tie	2 years	2 of 100 (Routine)

Climate Trend

35 complete years, 1894 to 2007

One stripe for each of 35 complete years at Koosharem, 1894 to 2007. Blue stripes are years cooler than the station's own mean of 6.6 C (43.9 F); red stripes are warmer. The coolest year was 1975, at 5.1 C (41.2 F), and the warmest was 2000, at 8.0 C (46.3 F). The strongest colour marks a difference of 1.5 C (2.7 F).

Annual mean temperature at Koosharem as warming stripes, 1894 to 2007
Year	Annual mean temperature	Difference from the station mean
1894	5.3 C	-1.33 C
1895	5.4 C	-1.22 C
1926	6.7 C	+0.05 C
1927	6.2 C	-0.42 C
1928	5.7 C	-0.92 C
1953	6.6 C	+0.04 C
1954	7.8 C	+1.16 C
1957	6.5 C	-0.13 C
1958	7.3 C	+0.66 C
1959	7.2 C	+0.55 C
1960	6.9 C	+0.26 C
1962	7.0 C	+0.40 C
1965	6.3 C	-0.32 C
1966	6.7 C	+0.06 C
1967	6.4 C	-0.24 C
1969	6.4 C	-0.17 C
1970	6.3 C	-0.33 C
1971	5.9 C	-0.75 C
1972	6.6 C	-0.01 C
1974	6.2 C	-0.41 C
1975	5.1 C	-1.49 C
1976	6.6 C	+0.04 C
1977	7.1 C	+0.52 C
1978	6.5 C	-0.13 C
1979	5.9 C	-0.73 C
1980	7.0 C	+0.40 C
1981	7.9 C	+1.25 C
1983	6.7 C	+0.05 C
1985	5.9 C	-0.66 C
1990	6.9 C	+0.33 C
1992	7.1 C	+0.53 C
2000	8.0 C	+1.35 C
2001	7.2 C	+0.64 C
2006	7.0 C	+0.36 C
2007	7.3 C	+0.73 C

The annual mean temperature here has risen by 0.1 C (0.1 to 0.2) per decade over 1894 to 2007. In Fahrenheit: 0.2 F (0.1 to 0.4) 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 Koosharem
Measure	Per decade (C)	Per decade (F)	Period	Complete years	Reading
Annual mean temperature	0.1 C (0.1 to 0.2) per decade	0.2 F (0.1 to 0.4) per decade	1894 to 2007	35	Rise
Mean daily maximum	0.2 C (0.1 to 0.3) per decade	0.3 F (0.1 to 0.5) per decade	1894 to 2007	35	Rise
Mean daily minimum	0.11 C (0.02 to 0.19) per decade	0.20 F (0.04 to 0.35) per decade	1894 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

1893 to 2009

Yearly extremes at Koosharem: the record and the median year
Measure	Record	Year of the record	Median year	Years with a value
Hottest day (TXx)	36.7 C (98.1 F)	1895	33.9 C (93.0 F)	74
Coldest night (TNn)	-35.6 C (-32.1 F)	1990	-26.1 C (-15.0 F)	74
Wettest day (Rx1day)	40.6 mm (1.6 in)	2005	20.3 mm (0.8 in)	78
Wettest five days (Rx5day)	81.1 mm (3.2 in)	1980	28.9 mm (1.1 in)	76
Longest dry spell (CDD)	103 days	1972	34 days	76

Hottest day (TXx)

The hottest day of the year at Koosharem, 1893 to 2009. The record is 36.7 C (98.1 F) in 1895, marked on the chart; the median year is 33.9 C (93.0 F).

Hottest day (TXx) at Koosharem by year
Year	Hottest day (TXx)
1893	33.9 C (93.0 F)
1894	32.2 C (90.0 F)
1895	36.7 C (98.1 F)
1896	32.2 C (90.0 F)
1897	28.3 C (82.9 F)
1909	n/a
1910	n/a
1919	20.0 C (68.0 F)
1920	33.3 C (91.9 F)
1921	33.9 C (93.0 F)
1922	33.9 C (93.0 F)
1923	23.9 C (75.0 F)
1924	15.6 C (60.1 F)
1925	32.8 C (91.0 F)
1926	32.2 C (90.0 F)
1927	33.3 C (91.9 F)
1928	31.1 C (88.0 F)
1929	10.0 C (50.0 F)
1948	n/a
1949	n/a
1950	n/a
1951	n/a
1952	32.8 C (91.0 F)
1953	35.6 C (96.1 F)
1954	35.0 C (95.0 F)
1955	35.6 C (96.1 F)
1956	33.3 C (91.9 F)
1957	32.8 C (91.0 F)
1958	35.0 C (95.0 F)
1959	34.4 C (93.9 F)
1960	36.1 C (97.0 F)
1961	34.4 C (93.9 F)
1962	33.9 C (93.0 F)
1963	33.9 C (93.0 F)
1964	33.9 C (93.0 F)
1965	31.1 C (88.0 F)
1966	32.8 C (91.0 F)
1967	33.3 C (91.9 F)
1968	32.8 C (91.0 F)
1969	32.8 C (91.0 F)
1970	33.9 C (93.0 F)
1971	34.4 C (93.9 F)
1972	34.4 C (93.9 F)
1973	35.0 C (95.0 F)
1974	33.9 C (93.0 F)
1975	32.2 C (90.0 F)
1976	36.1 C (97.0 F)
1977	35.0 C (95.0 F)
1978	35.0 C (95.0 F)
1979	35.0 C (95.0 F)
1980	34.4 C (93.9 F)
1981	35.0 C (95.0 F)
1982	32.8 C (91.0 F)
1983	32.8 C (91.0 F)
1984	32.8 C (91.0 F)
1985	35.0 C (95.0 F)
1986	33.3 C (91.9 F)
1987	35.6 C (96.1 F)
1988	34.4 C (93.9 F)
1989	36.7 C (98.1 F)
1990	33.9 C (93.0 F)
1991	33.3 C (91.9 F)
1992	32.8 C (91.0 F)
1993	32.2 C (90.0 F)
1994	35.0 C (95.0 F)
1995	35.6 C (96.1 F)
1996	35.0 C (95.0 F)
1997	33.3 C (91.9 F)
1998	33.9 C (93.0 F)
1999	32.8 C (91.0 F)
2000	35.6 C (96.1 F)
2001	33.3 C (91.9 F)
2002	35.6 C (96.1 F)
2003	35.6 C (96.1 F)
2004	31.7 C (89.1 F)
2005	30.6 C (87.1 F)
2006	35.0 C (95.0 F)
2007	34.4 C (93.9 F)
2008	30.6 C (87.1 F)
2009	20.0 C (68.0 F)

Coldest night (TNn)

The coldest night of the year at Koosharem, 1893 to 2009. The record is -35.6 C (-32.1 F) in 1990, marked on the chart; the median year is -26.1 C (-15.0 F).

Coldest night (TNn) at Koosharem by year
Year	Coldest night (TNn)
1893	-17.2 C (1.0 F)
1894	-27.2 C (-17.0 F)
1895	-27.8 C (-18.0 F)
1896	-19.4 C (-2.9 F)
1897	-26.1 C (-15.0 F)
1909	n/a
1910	n/a
1919	-31.7 C (-25.1 F)
1920	-22.8 C (-9.0 F)
1921	-20.6 C (-5.1 F)
1922	-30.6 C (-23.1 F)
1923	-26.1 C (-15.0 F)
1924	-28.9 C (-20.0 F)
1925	-15.0 C (5.0 F)
1926	-26.7 C (-16.1 F)
1927	-26.1 C (-15.0 F)
1928	-26.1 C (-15.0 F)
1929	-31.1 C (-24.0 F)
1948	n/a
1949	n/a
1950	n/a
1951	n/a
1952	-27.2 C (-17.0 F)
1953	-22.8 C (-9.0 F)
1954	-19.4 C (-2.9 F)
1955	-27.8 C (-18.0 F)
1956	-24.4 C (-11.9 F)
1957	-27.8 C (-18.0 F)
1958	-23.9 C (-11.0 F)
1959	-25.6 C (-14.1 F)
1960	-25.6 C (-14.1 F)
1961	-28.3 C (-18.9 F)
1962	-30.0 C (-22.0 F)
1963	-33.3 C (-27.9 F)
1964	-26.7 C (-16.1 F)
1965	-23.3 C (-9.9 F)
1966	-26.1 C (-15.0 F)
1967	-26.7 C (-16.1 F)
1968	-27.8 C (-18.0 F)
1969	-25.0 C (-13.0 F)
1970	-28.3 C (-18.9 F)
1971	-31.1 C (-24.0 F)
1972	-33.3 C (-27.9 F)
1973	-27.2 C (-17.0 F)
1974	-26.1 C (-15.0 F)
1975	-24.4 C (-11.9 F)
1976	-27.2 C (-17.0 F)
1977	-24.4 C (-11.9 F)
1978	-25.6 C (-14.1 F)
1979	-30.6 C (-23.1 F)
1980	-21.7 C (-7.1 F)
1981	-20.6 C (-5.1 F)
1982	-30.0 C (-22.0 F)
1983	-22.8 C (-9.0 F)
1984	-28.9 C (-20.0 F)
1985	-31.1 C (-24.0 F)
1986	-23.3 C (-9.9 F)
1987	-26.1 C (-15.0 F)
1988	-28.9 C (-20.0 F)
1989	-28.9 C (-20.0 F)
1990	-35.6 C (-32.1 F)
1991	-24.4 C (-11.9 F)
1992	-25.6 C (-14.1 F)
1993	-26.1 C (-15.0 F)
1994	-24.4 C (-11.9 F)
1995	-21.7 C (-7.1 F)
1996	-22.8 C (-9.0 F)
1997	-27.2 C (-17.0 F)
1998	-27.8 C (-18.0 F)
1999	-18.9 C (-2.0 F)
2000	-20.6 C (-5.1 F)
2001	-23.3 C (-9.9 F)
2002	-21.7 C (-7.1 F)
2003	-21.7 C (-7.1 F)
2004	-28.9 C (-20.0 F)
2005	-21.7 C (-7.1 F)
2006	-24.4 C (-11.9 F)
2007	-26.7 C (-16.1 F)
2008	-26.7 C (-16.1 F)
2009	-26.1 C (-15.0 F)

Wettest day (Rx1day)

The wettest day of the year at Koosharem, 1893 to 2009. The record is 40.6 mm (1.6 in) in 2005, marked on the chart; the median year is 20.3 mm (0.8 in).

Wettest day (Rx1day) at Koosharem by year
Year	Wettest day (Rx1day)
1893	20.1 mm (0.8 in)
1894	18.5 mm (0.7 in)
1895	17.8 mm (0.7 in)
1896	31.0 mm (1.2 in)
1897	20.3 mm (0.8 in)
1909	n/a
1910	n/a
1919	7.6 mm (0.30 in)
1920	12.2 mm (0.5 in)
1921	15.2 mm (0.6 in)
1922	38.1 mm (1.5 in)
1923	12.2 mm (0.5 in)
1924	12.7 mm (0.5 in)
1925	26.7 mm (1.1 in)
1926	12.7 mm (0.5 in)
1927	30.7 mm (1.2 in)
1928	25.4 mm (1.0 in)
1929	24.1 mm (0.9 in)
1948	25.4 mm (1.0 in)
1949	27.4 mm (1.1 in)
1950	16.0 mm (0.6 in)
1951	17.8 mm (0.7 in)
1952	22.9 mm (0.9 in)
1953	27.9 mm (1.1 in)
1954	20.8 mm (0.8 in)
1955	18.8 mm (0.7 in)
1956	15.2 mm (0.6 in)
1957	17.0 mm (0.7 in)
1958	21.6 mm (0.9 in)
1959	19.1 mm (0.8 in)
1960	19.3 mm (0.8 in)
1961	16.5 mm (0.6 in)
1962	10.9 mm (0.4 in)
1963	14.7 mm (0.6 in)
1964	14.7 mm (0.6 in)
1965	23.9 mm (0.9 in)
1966	17.5 mm (0.7 in)
1967	33.8 mm (1.3 in)
1968	18.0 mm (0.7 in)
1969	20.8 mm (0.8 in)
1970	22.1 mm (0.9 in)
1971	26.9 mm (1.1 in)
1972	27.7 mm (1.1 in)
1973	13.0 mm (0.5 in)
1974	24.6 mm (1.0 in)
1975	11.7 mm (0.5 in)
1976	19.3 mm (0.8 in)
1977	12.7 mm (0.5 in)
1978	31.0 mm (1.2 in)
1979	15.5 mm (0.6 in)
1980	24.9 mm (1.0 in)
1981	28.7 mm (1.1 in)
1982	29.0 mm (1.1 in)
1983	20.3 mm (0.8 in)
1984	37.1 mm (1.5 in)
1985	19.6 mm (0.8 in)
1986	15.5 mm (0.6 in)
1987	22.1 mm (0.9 in)
1988	21.1 mm (0.8 in)
1989	15.5 mm (0.6 in)
1990	13.0 mm (0.5 in)
1991	21.1 mm (0.8 in)
1992	26.7 mm (1.1 in)
1993	19.8 mm (0.8 in)
1994	15.2 mm (0.6 in)
1995	25.4 mm (1.0 in)
1996	16.5 mm (0.6 in)
1997	27.2 mm (1.1 in)
1998	20.3 mm (0.8 in)
1999	20.8 mm (0.8 in)
2000	27.4 mm (1.1 in)
2001	20.3 mm (0.8 in)
2002	25.4 mm (1.0 in)
2003	20.8 mm (0.8 in)
2004	35.6 mm (1.4 in)
2005	40.6 mm (1.6 in)
2006	30.7 mm (1.2 in)
2007	39.6 mm (1.6 in)
2008	14.0 mm (0.6 in)
2009	13.2 mm (0.5 in)

Wettest five days (Rx5day)

The wettest five days of the year at Koosharem, 1893 to 2009. The record is 81.1 mm (3.2 in) in 1980, marked on the chart; the median year is 28.9 mm (1.1 in).

Wettest five days (Rx5day) at Koosharem by year
Year	Wettest five days (Rx5day)
1893	21.4 mm (0.8 in)
1894	8.4 mm (0.33 in)
1895	23.4 mm (0.9 in)
1896	76.5 mm (3.0 in)
1897	20.3 mm (0.8 in)
1909	n/a
1910	n/a
1919	n/a
1920	n/a
1921	4.1 mm (0.16 in)
1922	27.9 mm (1.1 in)
1923	14.2 mm (0.6 in)
1924	16.7 mm (0.7 in)
1925	12.2 mm (0.5 in)
1926	13.4 mm (0.5 in)
1927	51.5 mm (2.0 in)
1928	24.0 mm (0.9 in)
1929	55.9 mm (2.2 in)
1948	26.7 mm (1.1 in)
1949	34.8 mm (1.4 in)
1950	26.7 mm (1.1 in)
1951	28.8 mm (1.1 in)
1952	23.8 mm (0.9 in)
1953	32.9 mm (1.3 in)
1954	35.8 mm (1.4 in)
1955	24.6 mm (1.0 in)
1956	30.5 mm (1.2 in)
1957	41.6 mm (1.6 in)
1958	23.9 mm (0.9 in)
1959	31.0 mm (1.2 in)
1960	37.6 mm (1.5 in)
1961	30.7 mm (1.2 in)
1962	16.2 mm (0.6 in)
1963	37.0 mm (1.5 in)
1964	29.4 mm (1.2 in)
1965	32.0 mm (1.3 in)
1966	24.4 mm (1.0 in)
1967	73.6 mm (2.9 in)
1968	25.6 mm (1.0 in)
1969	33.4 mm (1.3 in)
1970	31.3 mm (1.2 in)
1971	51.8 mm (2.0 in)
1972	40.4 mm (1.6 in)
1973	20.4 mm (0.8 in)
1974	28.4 mm (1.1 in)
1975	18.5 mm (0.7 in)
1976	20.1 mm (0.8 in)
1977	27.7 mm (1.1 in)
1978	38.1 mm (1.5 in)
1979	34.3 mm (1.4 in)
1980	81.1 mm (3.2 in)
1981	32.8 mm (1.3 in)
1982	61.2 mm (2.4 in)
1983	35.6 mm (1.4 in)
1984	44.9 mm (1.8 in)
1985	36.2 mm (1.4 in)
1986	18.5 mm (0.7 in)
1987	28.1 mm (1.1 in)
1988	28.1 mm (1.1 in)
1989	18.0 mm (0.7 in)
1990	30.1 mm (1.2 in)
1991	26.9 mm (1.1 in)
1992	40.2 mm (1.6 in)
1993	28.7 mm (1.1 in)
1994	34.0 mm (1.3 in)
1995	27.7 mm (1.1 in)
1996	21.3 mm (0.8 in)
1997	43.9 mm (1.7 in)
1998	27.4 mm (1.1 in)
1999	26.6 mm (1.0 in)
2000	42.2 mm (1.7 in)
2001	29.0 mm (1.1 in)
2002	47.9 mm (1.9 in)
2003	24.1 mm (0.9 in)
2004	63.5 mm (2.5 in)
2005	40.6 mm (1.6 in)
2006	52.0 mm (2.0 in)
2007	61.4 mm (2.4 in)
2008	20.1 mm (0.8 in)
2009	13.2 mm (0.5 in)

Longest dry spell (CDD)

The longest dry spell of the year at Koosharem, 1893 to 2009. The record is 103 days in 1972, marked on the chart; the median year is 34 days.

Longest dry spell (CDD) at Koosharem by year
Year	Longest dry spell (CDD)
1893	30 days
1894	34 days
1895	31 days
1896	37 days
1897	19 days
1909	n/a
1910	n/a
1919	n/a
1920	2 days
1921	8 days
1922	10 days
1923	33 days
1924	11 days
1925	13 days
1926	29 days
1927	34 days
1928	1 day
1929	n/a
1948	13 days
1949	64 days
1950	97 days
1951	34 days
1952	54 days
1953	44 days
1954	39 days
1955	44 days
1956	45 days
1957	33 days
1958	42 days
1959	37 days
1960	34 days
1961	32 days
1962	53 days
1963	26 days
1964	46 days
1965	31 days
1966	49 days
1967	33 days
1968	27 days
1969	34 days
1970	36 days
1971	36 days
1972	103 days
1973	43 days
1974	97 days
1975	27 days
1976	47 days
1977	49 days
1978	47 days
1979	48 days
1980	36 days
1981	29 days
1982	29 days
1983	23 days
1984	30 days
1985	42 days
1986	27 days
1987	22 days
1988	29 days
1989	46 days
1990	30 days
1991	32 days
1992	34 days
1993	35 days
1994	30 days
1995	31 days
1996	34 days
1997	38 days
1998	38 days
1999	45 days
2000	52 days
2001	40 days
2002	53 days
2003	32 days
2004	34 days
2005	28 days
2006	61 days
2007	35 days
2008	25 days
2009	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

35 years with a frost

Across 35 years with a frost, the median last spring frost at Koosharem falls on 15 June and the median first autumn frost on 9 September, which leaves a median of 86 days between them.

Fitted over all years, the growing season changes by +0.4 days per decade at this station.

Frost dates and growing season at Koosharem
Measure	Median, all years	Earliest period	Recent period (1953 to 2007)	Recent against earliest	Fitted trend
Last spring frost	15 June	n/a	15 June	n/a	-0.7 days per decade
First autumn frost	9 September	n/a	10 September	n/a	-0.3 days per decade
Growing days	86 days	n/a	90 days	n/a	+0.4 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

56 years, 1949 to 2007

A day with at least 21.0 mm (0.8 in) of rain is expected about once in 2 years. A day with at least 44.2 mm (1.7 in) of rain is expected about once in 100 years.

Rainfall return levels at Koosharem: the daily rain expected about once in a given number of years
Expected about once in	A day with at least	Note
2 years	21.0 mm (0.8 in)
5 years	27.5 mm (1.1 in)
10 years	31.6 mm (1.2 in)
25 years	36.8 mm (1.4 in)
50 years	40.6 mm (1.6 in)
100 years	44.2 mm (1.7 in)	Longer than the 56 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, 56 years of values from 1949 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: 40.6 mm (1.6 in) in 2005; 39.6 mm (1.6 in) in 2007; 37.1 mm (1.5 in) in 1984.

Download the Data

Data for Koosharem standing records by year: CSV or JSON. Field meanings are on the data page.
Data for Koosharem 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 2026-10-17 (17 October 2026). Records are computed by this site and are not official.

Data as of 2025-12-31. Last revised 31 December 2025 (2025-12-31).