Challis Weather Records (USC00101663)

Record envelope, standing records and threshold days for Challis (USC00101663), Idaho, United States, with 102 years of record.

Key Facts for Challis

Challis (USC00101663) is a weather station in Idaho, United States at 44.50 latitude and -114.24 longitude, 1,577 m (5,175 ft) above sea level.
The station reports from 1895 to 1996, 102 years of record.
1,464 records set at Challis still stand.
Records are tracked for tmax, tmin, prcp, snow, snwd: an element needs 30 years of data to be eligible.
Challis set a daily record precipitation of 11.9 mm (0.5 in) on 25 June 1996.

About the Station

Location: Idaho, United States, 44.50 latitude, -114.24 longitude.
Elevation: 1,577 m (5,175 ft).
Period of record: 1895 to 1996, 102 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 Challis. 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 Challis, with 2026 drawn through them
Month	Highest record high	Lowest record low	2026 highest maximum	2026 lowest minimum
Jan	15.6 C (60.1 F)	-36.1 C (-33.0 F)	n/a	n/a
Feb	18.3 C (64.9 F)	-35.0 C (-31.0 F)	n/a	n/a
Mar	23.3 C (73.9 F)	-26.7 C (-16.1 F)	n/a	n/a
Apr	30.6 C (87.1 F)	-16.1 C (3.0 F)	n/a	n/a
May	33.9 C (93.0 F)	-9.4 C (15.1 F)	n/a	n/a
Jun	37.8 C (100.0 F)	-4.4 C (24.1 F)	n/a	n/a
Jul	39.4 C (102.9 F)	-0.6 C (30.9 F)	n/a	n/a
Aug	39.4 C (102.9 F)	-6.7 C (19.9 F)	n/a	n/a
Sep	34.4 C (93.9 F)	-8.3 C (17.1 F)	n/a	n/a
Oct	31.7 C (89.1 F)	-17.2 C (1.0 F)	n/a	n/a
Nov	23.9 C (75.0 F)	-27.2 C (-17.0 F)	n/a	n/a
Dec	15.6 C (60.1 F)	-36.7 C (-34.1 F)	n/a	n/a

Which Years Hold Standing Records

1,464 standing records

1,464 records at Challis still stand. 1914 holds the most, with 54.

Standing records at Challis by the year they were set
Year set	Standing records
1895	15
1896	7
1897	7
1898	14
1899	12
1900	18
1901	2
1914	54
1915	18
1916	42
1917	24
1918	11
1919	24
1920	11
1921	20
1922	23
1923	5
1924	31
1925	7
1926	20
1927	38
1928	21
1929	24
1930	14
1931	18
1932	13
1933	34
1934	19
1935	13
1936	19
1937	27
1938	7
1939	18
1940	20
1941	6
1942	23
1943	8
1944	8
1945	13
1946	8
1947	7
1948	15
1949	25
1950	20
1951	18
1952	10
1953	13
1954	17
1955	19
1956	11
1957	5
1958	8
1959	16
1960	24
1961	16
1962	11
1963	19
1964	7
1965	16
1966	26
1967	19
1968	17
1969	30
1970	14
1971	13
1972	23
1973	7
1974	16
1975	13
1976	6
1977	16
1978	12
1979	14
1980	10
1981	9
1982	9
1983	20
1984	16
1985	28
1986	16
1987	15
1988	17
1989	14
1990	23
1991	8
1992	17
1993	5
1994	19
1995	12
1996	7

All-Time Record Progression

10 new records

10 all-time records were set at Challis between 25 January 1949 and 8 November 1985. Each dot is a new record.

When Challis set new all-time records
Date	Kind	Detail
1949-01-25	Record low minimum temperature	Record low minimum temperature -36.1 C (-33.0 F)
1950-09-09	Record daily precipitation	Record daily precipitation 40.6 mm (1.6 in)
1960-07-20	Record high maximum temperature	Record high maximum temperature 38.9 C (102.0 F)
1961-08-04	Record high maximum temperature	Record high maximum temperature 39.4 C (102.9 F)
1963-04-01	Record daily snowfall	Record daily snowfall 21.6 cm (8.5 in)
1964-12-22	Record daily precipitation	Record daily precipitation 41.1 mm (1.6 in)
1983-07-10	Record daily precipitation	Record daily precipitation 47.0 mm (1.9 in)
1983-12-22	Record low maximum temperature	Record low maximum temperature -25.6 C (-14.1 F)
1983-12-23	Record low minimum temperature	Record low minimum temperature -36.7 C (-34.1 F)
1985-11-08	Record daily snowfall	Record daily snowfall 27.9 cm (11.0 in)

Wettest Day of Each Month

Jul: 47.0 mm (1.9 in)

The wettest day on record for each calendar month at Challis. The most was 47.0 mm (1.9 in) on 10 July 1983.

Record daily precipitation for each month at Challis
Month	Record daily precipitation (mm)	Date
Jan	35.6 mm (1.4 in)	14 January 1915
Feb	27.7 mm (1.1 in)	25 February 1917
Mar	15.7 mm (0.6 in)	18 March 1921
Apr	22.9 mm (0.9 in)	14 April 1973
May	31.8 mm (1.3 in)	9 May 1918
Jun	32.5 mm (1.3 in)	21 June 1948
Jul	47.0 mm (1.9 in)	10 July 1983
Aug	19.1 mm (0.8 in)	20 August 1974
Sep	40.6 mm (1.6 in)	9 September 1950
Oct	27.9 mm (1.1 in)	10 October 1915
Nov	21.6 mm (0.9 in)	21 November 1946
Dec	41.1 mm (1.6 in)	22 December 1964

Period of Record Coverage

1895 to 1996

91 years of record at Challis, 1895 to 1996. 16 years have data for under 90 percent of days and are left out of rankings: 1895, 1896, 1897, 1898, 1899, 1900, 1901, 1902 and others.

Days with data per year at Challis
Year	Days with data	Share of year	Complete
1895	178	49%	No
1896	152	42%	No
1897	92	25%	No
1898	151	41%	No
1899	242	66%	No
1900	243	67%	No
1901	57	16%	No
1902	59	16%	No
1914	360	99%	Yes
1915	354	97%	Yes
1916	365	100%	Yes
1917	364	100%	Yes
1918	363	99%	Yes
1919	364	100%	Yes
1920	366	100%	Yes
1921	364	100%	Yes
1922	363	99%	Yes
1923	364	100%	Yes
1924	357	98%	Yes
1925	331	91%	Yes
1926	338	93%	Yes
1927	328	90%	No
1928	348	95%	Yes
1929	329	90%	Yes
1930	359	98%	Yes
1931	318	87%	No
1932	295	81%	No
1933	344	94%	Yes
1934	348	95%	Yes
1935	365	100%	Yes
1936	364	99%	Yes
1937	360	99%	Yes
1938	362	99%	Yes
1939	363	99%	Yes
1940	355	97%	Yes
1941	365	100%	Yes
1942	365	100%	Yes
1943	354	97%	Yes
1944	358	98%	Yes
1945	348	95%	Yes
1946	360	99%	Yes
1947	360	99%	Yes
1948	357	98%	Yes
1949	353	97%	Yes
1950	365	100%	Yes
1951	361	99%	Yes
1952	361	99%	Yes
1953	351	96%	Yes
1954	344	94%	Yes
1955	357	98%	Yes
1956	352	96%	Yes
1957	358	98%	Yes
1958	331	91%	Yes
1959	346	95%	Yes
1960	354	97%	Yes
1961	360	99%	Yes
1962	362	99%	Yes
1963	352	96%	Yes
1964	270	74%	No
1965	363	99%	Yes
1966	363	99%	Yes
1967	365	100%	Yes
1968	365	100%	Yes
1969	364	100%	Yes
1970	365	100%	Yes
1971	365	100%	Yes
1972	356	97%	Yes
1973	361	99%	Yes
1974	363	99%	Yes
1975	351	96%	Yes
1976	362	99%	Yes
1977	363	99%	Yes
1978	365	100%	Yes
1979	332	91%	Yes
1980	360	98%	Yes
1981	365	100%	Yes
1982	353	97%	Yes
1983	360	99%	Yes
1984	360	98%	Yes
1985	365	100%	Yes
1986	365	100%	Yes
1987	356	98%	Yes
1988	358	98%	Yes
1989	361	99%	Yes
1990	358	98%	Yes
1991	342	94%	Yes
1992	335	92%	Yes
1993	305	84%	No
1994	299	82%	No
1995	281	77%	No
1996	146	40%	No

Latest Records

Latest records at Challis
Date	Station	Record	Value	Beat old record by	Old record stood	Significance
25 June 1996	Challis, US	daily rain	11.9 mm (0.5 in)	5.8 mm (0.23 in)	5 years	20 of 100 (Routine)
17 June 1996	Challis, US	daily high min	15.6 C (60.1 F)	1.7 C (3.1 F)	8 years	16 of 100 (Routine)
9 June 1996	Challis, US	daily high max (Tie)	31.1 C (88.0 F)	tie	44 years	5 of 100 (Routine)
8 June 1996	Challis, US	daily high max (Tie)	31.7 C (89.1 F)	tie	20 years	4 of 100 (Routine)
7 June 1996	Challis, US	daily high max	32.2 C (90.0 F)	0.5 C (0.9 F)	66 years	29 of 100 (Routine)
20 April 1996	Challis, US	daily snowfall	7.6 cm (3.0 in)	7.6 cm (3.0 in)	99 years	54 of 100 (Notable)
9 April 1996	Challis, US	daily high max	25.6 C (78.1 F)	1.7 C (3.1 F)	97 years	42 of 100 (Notable)
29 March 1996	Challis, US	daily snowfall	2.5 cm (1.0 in)	2.5 cm (1.0 in)	100 years	20 of 100 (Routine)
28 March 1996	Challis, US	daily snowfall	5.1 cm (2.0 in)	2.6 cm (1.0 in)	65 years	37 of 100 (Notable)
25 March 1996	Challis, US	daily low min (Tie)	-12.2 C (10.0 F)	tie	60 years	7 of 100 (Routine)
13 March 1996	Challis, US	daily rain	10.7 mm (0.4 in)	6.1 mm (0.24 in)	53 years	20 of 100 (Routine)
4 March 1996	Challis, US	daily snowfall (Tie)	2.5 cm (1.0 in)	tie	96 years	9 of 100 (Routine)
18 February 1996	Challis, US	daily high min (Tie)	1.7 C (35.1 F)	tie	46 years	6 of 100 (Routine)
9 February 1996	Challis, US	daily high min	3.9 C (39.0 F)	5.0 C (9.0 F)	73 years	40 of 100 (Notable)
9 February 1996	Challis, US	daily high max	11.7 C (53.1 F)	2.3 C (4.1 F)	32 years	23 of 100 (Routine)
8 February 1996	Challis, US	daily high min	3.3 C (37.9 F)	2.7 C (4.9 F)	72 years	35 of 100 (Notable)
7 February 1996	Challis, US	monthly high min	5.0 C (41.0 F)	1.1 C (2.0 F)	45 years	34 of 100 (Routine)
7 February 1996	Challis, US	daily high max (Tie)	11.7 C (53.1 F)	tie	32 years	4 of 100 (Routine)
3 February 1996	Challis, US	daily low min (Tie)	-26.7 C (-16.1 F)	tie	45 years	5 of 100 (Routine)
28 January 1996	Challis, US	daily snowfall (Tie)	5.1 cm (2.0 in)	tie	45 years	5 of 100 (Routine)

Climate Trend

68 complete years, 1914 to 1995

One stripe for each of 68 complete years at Challis, 1914 to 1995. Blue stripes are years cooler than the station's own mean of 6.7 C (44.1 F); red stripes are warmer. The coolest year was 1922, at 4.3 C (39.7 F), and the warmest was 1934, at 9.3 C (48.8 F). The strongest colour marks a difference of 2.6 C (4.7 F).

Annual mean temperature at Challis as warming stripes, 1914 to 1995
Year	Annual mean temperature	Difference from the station mean
1914	4.6 C	-2.14 C
1916	4.9 C	-1.84 C
1917	6.2 C	-0.53 C
1918	5.9 C	-0.86 C
1919	5.6 C	-1.15 C
1920	5.2 C	-1.53 C
1921	6.3 C	-0.44 C
1922	4.3 C	-2.47 C
1923	5.5 C	-1.25 C
1924	4.8 C	-1.96 C
1928	6.8 C	+0.10 C
1929	6.2 C	-0.48 C
1930	6.0 C	-0.68 C
1933	7.5 C	+0.75 C
1934	9.3 C	+2.59 C
1935	6.3 C	-0.45 C
1936	6.8 C	+0.09 C
1937	6.6 C	-0.14 C
1938	7.2 C	+0.45 C
1939	8.1 C	+1.35 C
1940	8.0 C	+1.31 C
1941	6.9 C	+0.13 C
1942	5.3 C	-1.47 C
1943	6.2 C	-0.54 C
1944	5.7 C	-1.07 C
1945	6.7 C	-0.06 C
1946	7.0 C	+0.26 C
1947	7.0 C	+0.26 C
1948	6.2 C	-0.55 C
1949	6.4 C	-0.28 C
1950	7.0 C	+0.30 C
1951	6.0 C	-0.77 C
1952	6.0 C	-0.70 C
1953	7.8 C	+1.09 C
1956	6.2 C	-0.54 C
1957	6.4 C	-0.33 C
1959	7.1 C	+0.33 C
1960	6.8 C	+0.10 C
1961	7.9 C	+1.13 C
1962	7.2 C	+0.43 C
1965	6.9 C	+0.18 C
1966	8.3 C	+1.59 C
1967	8.0 C	+1.32 C
1968	7.2 C	+0.46 C
1969	7.8 C	+1.12 C
1970	7.6 C	+0.84 C
1971	6.8 C	+0.08 C
1972	7.3 C	+0.59 C
1973	6.8 C	+0.12 C
1974	6.8 C	+0.03 C
1976	6.1 C	-0.60 C
1977	7.0 C	+0.29 C
1978	6.4 C	-0.36 C
1980	6.9 C	+0.21 C
1981	7.5 C	+0.81 C
1983	6.4 C	-0.34 C
1984	5.1 C	-1.67 C
1985	4.7 C	-2.01 C
1986	7.0 C	+0.26 C
1987	7.6 C	+0.90 C
1988	7.6 C	+0.90 C
1989	7.5 C	+0.79 C
1990	7.9 C	+1.19 C
1991	7.5 C	+0.79 C
1992	8.5 C	+1.79 C
1993	5.9 C	-0.82 C
1994	8.5 C	+1.74 C
1995	7.9 C	+1.20 C

The annual mean temperature here has risen by 0.2 C (0.1 to 0.3) per decade over 1914 to 1995. In Fahrenheit: 0.4 F (0.2 to 0.5) per decade. The slope is a straight line fitted to 68 complete years; the brackets give its 95 percent interval.

Fitted temperature trends per decade at Challis
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 0.5) per decade	1914 to 1995	68	Rise
Mean daily maximum	0.08 C (-0.03 to 0.20) per decade	0.1 F (-0.1 to 0.4) per decade	1914 to 1995	68	Not clearly different from zero
Mean daily minimum	0.3 C (0.2 to 0.4) per decade	0.6 F (0.4 to 0.7) per decade	1914 to 1995	68	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

1895 to 1996

Yearly extremes at Challis: the record and the median year
Measure	Record	Year of the record	Median year	Years with a value
Hottest day (TXx)	39.4 C (102.9 F)	1961	35.6 C (96.1 F)	91
Coldest night (TNn)	-36.7 C (-34.1 F)	1983	-27.2 C (-17.0 F)	91
Wettest day (Rx1day)	47.0 mm (1.9 in)	1983	17.3 mm (0.7 in)	91
Wettest five days (Rx5day)	72.1 mm (2.8 in)	1964	27.9 mm (1.1 in)	91
Longest dry spell (CDD)	98 days	1976	43 days	91

Hottest day (TXx)

The hottest day of the year at Challis, 1895 to 1996. The record is 39.4 C (102.9 F) in 1961, marked on the chart; the median year is 35.6 C (96.1 F).

Hottest day (TXx) at Challis by year
Year	Hottest day (TXx)
1895	26.1 C (79.0 F)
1896	28.9 C (84.0 F)
1897	37.8 C (100.0 F)
1898	28.3 C (82.9 F)
1899	38.3 C (100.9 F)
1900	36.1 C (97.0 F)
1901	11.1 C (52.0 F)
1902	7.8 C (46.0 F)
1914	35.0 C (95.0 F)
1915	34.4 C (93.9 F)
1916	33.9 C (93.0 F)
1917	35.0 C (95.0 F)
1918	33.3 C (91.9 F)
1919	35.0 C (95.0 F)
1920	33.9 C (93.0 F)
1921	34.4 C (93.9 F)
1922	32.8 C (91.0 F)
1923	33.3 C (91.9 F)
1924	33.3 C (91.9 F)
1925	35.6 C (96.1 F)
1926	33.3 C (91.9 F)
1927	35.6 C (96.1 F)
1928	38.3 C (100.9 F)
1929	37.8 C (100.0 F)
1930	37.2 C (99.0 F)
1931	36.1 C (97.0 F)
1932	36.1 C (97.0 F)
1933	37.8 C (100.0 F)
1934	36.7 C (98.1 F)
1935	36.1 C (97.0 F)
1936	36.7 C (98.1 F)
1937	36.7 C (98.1 F)
1938	32.8 C (91.0 F)
1939	35.6 C (96.1 F)
1940	36.7 C (98.1 F)
1941	33.3 C (91.9 F)
1942	35.0 C (95.0 F)
1943	34.4 C (93.9 F)
1944	32.2 C (90.0 F)
1945	35.6 C (96.1 F)
1946	35.6 C (96.1 F)
1947	32.8 C (91.0 F)
1948	34.4 C (93.9 F)
1949	36.1 C (97.0 F)
1950	34.4 C (93.9 F)
1951	35.6 C (96.1 F)
1952	33.9 C (93.0 F)
1953	35.0 C (95.0 F)
1954	35.6 C (96.1 F)
1955	35.6 C (96.1 F)
1956	34.4 C (93.9 F)
1957	34.4 C (93.9 F)
1958	35.6 C (96.1 F)
1959	38.3 C (100.9 F)
1960	38.9 C (102.0 F)
1961	39.4 C (102.9 F)
1962	35.6 C (96.1 F)
1963	35.6 C (96.1 F)
1964	39.4 C (102.9 F)
1965	34.4 C (93.9 F)
1966	36.7 C (98.1 F)
1967	36.1 C (97.0 F)
1968	35.6 C (96.1 F)
1969	37.2 C (99.0 F)
1970	36.1 C (97.0 F)
1971	35.0 C (95.0 F)
1972	37.2 C (99.0 F)
1973	37.2 C (99.0 F)
1974	36.7 C (98.1 F)
1975	36.1 C (97.0 F)
1976	35.6 C (96.1 F)
1977	34.4 C (93.9 F)
1978	34.4 C (93.9 F)
1979	36.1 C (97.0 F)
1980	35.6 C (96.1 F)
1981	36.7 C (98.1 F)
1982	34.4 C (93.9 F)
1983	36.1 C (97.0 F)
1984	34.4 C (93.9 F)
1985	36.1 C (97.0 F)
1986	35.0 C (95.0 F)
1987	33.9 C (93.0 F)
1988	36.7 C (98.1 F)
1989	35.6 C (96.1 F)
1990	36.7 C (98.1 F)
1991	35.0 C (95.0 F)
1992	37.8 C (100.0 F)
1993	33.9 C (93.0 F)
1994	36.7 C (98.1 F)
1995	35.0 C (95.0 F)
1996	32.2 C (90.0 F)

Coldest night (TNn)

The coldest night of the year at Challis, 1895 to 1996. The record is -36.7 C (-34.1 F) in 1983, marked on the chart; the median year is -27.2 C (-17.0 F).

Coldest night (TNn) at Challis by year
Year	Coldest night (TNn)
1895	-28.9 C (-20.0 F)
1896	-25.6 C (-14.1 F)
1897	1.1 C (34.0 F)
1898	-23.9 C (-11.0 F)
1899	-30.0 C (-22.0 F)
1900	-20.6 C (-5.1 F)
1901	-24.4 C (-11.9 F)
1902	-28.9 C (-20.0 F)
1914	-30.0 C (-22.0 F)
1915	-32.2 C (-26.0 F)
1916	-31.7 C (-25.1 F)
1917	-27.2 C (-17.0 F)
1918	-25.0 C (-13.0 F)
1919	-33.9 C (-29.0 F)
1920	-26.1 C (-15.0 F)
1921	-21.7 C (-7.1 F)
1922	-33.3 C (-27.9 F)
1923	-23.9 C (-11.0 F)
1924	-33.9 C (-29.0 F)
1925	-18.3 C (-0.9 F)
1926	-23.9 C (-11.0 F)
1927	-28.3 C (-18.9 F)
1928	-24.4 C (-11.9 F)
1929	-30.6 C (-23.1 F)
1930	-34.4 C (-29.9 F)
1931	-27.2 C (-17.0 F)
1932	-33.3 C (-27.9 F)
1933	-35.0 C (-31.0 F)
1934	-16.1 C (3.0 F)
1935	-28.3 C (-18.9 F)
1936	-29.4 C (-20.9 F)
1937	-35.6 C (-32.1 F)
1938	-21.1 C (-6.0 F)
1939	-24.4 C (-11.9 F)
1940	-22.8 C (-9.0 F)
1941	-23.3 C (-9.9 F)
1942	-31.7 C (-25.1 F)
1943	-30.0 C (-22.0 F)
1944	-26.1 C (-15.0 F)
1945	-22.8 C (-9.0 F)
1946	-19.4 C (-2.9 F)
1947	-27.2 C (-17.0 F)
1948	-29.4 C (-20.9 F)
1949	-36.1 C (-33.0 F)
1950	-26.7 C (-16.1 F)
1951	-32.8 C (-27.0 F)
1952	-25.6 C (-14.1 F)
1953	-18.3 C (-0.9 F)
1954	-21.7 C (-7.1 F)
1955	-23.3 C (-9.9 F)
1956	-33.3 C (-27.9 F)
1957	-32.2 C (-26.0 F)
1958	-23.9 C (-11.0 F)
1959	-26.7 C (-16.1 F)
1960	-28.3 C (-18.9 F)
1961	-25.0 C (-13.0 F)
1962	-35.6 C (-32.1 F)
1963	-31.1 C (-24.0 F)
1964	-28.9 C (-20.0 F)
1965	-17.8 C (0.0 F)
1966	-19.4 C (-2.9 F)
1967	-22.8 C (-9.0 F)
1968	-21.7 C (-7.1 F)
1969	-18.9 C (-2.0 F)
1970	-25.0 C (-13.0 F)
1971	-28.3 C (-18.9 F)
1972	-31.7 C (-25.1 F)
1973	-25.0 C (-13.0 F)
1974	-29.4 C (-20.9 F)
1975	-23.9 C (-11.0 F)
1976	-23.9 C (-11.0 F)
1977	-24.4 C (-11.9 F)
1978	-31.1 C (-24.0 F)
1979	-32.8 C (-27.0 F)
1980	-28.3 C (-18.9 F)
1981	-20.6 C (-5.1 F)
1982	-29.4 C (-20.9 F)
1983	-36.7 C (-34.1 F)
1984	-30.6 C (-23.1 F)
1985	-28.3 C (-18.9 F)
1986	-22.2 C (-8.0 F)
1987	-23.3 C (-9.9 F)
1988	-25.6 C (-14.1 F)
1989	-31.1 C (-24.0 F)
1990	-36.7 C (-34.1 F)
1991	-22.8 C (-9.0 F)
1992	-27.2 C (-17.0 F)
1993	-27.2 C (-17.0 F)
1994	-25.0 C (-13.0 F)
1995	-27.2 C (-17.0 F)
1996	-26.7 C (-16.1 F)

Wettest day (Rx1day)

The wettest day of the year at Challis, 1895 to 1996. The record is 47.0 mm (1.9 in) in 1983, marked on the chart; the median year is 17.3 mm (0.7 in).

Wettest day (Rx1day) at Challis by year
Year	Wettest day (Rx1day)
1895	10.2 mm (0.4 in)
1896	7.6 mm (0.30 in)
1897	12.7 mm (0.5 in)
1898	23.4 mm (0.9 in)
1899	20.3 mm (0.8 in)
1900	11.7 mm (0.5 in)
1901	12.7 mm (0.5 in)
1902	7.6 mm (0.30 in)
1914	16.3 mm (0.6 in)
1915	35.6 mm (1.4 in)
1916	9.1 mm (0.36 in)
1917	27.7 mm (1.1 in)
1918	31.8 mm (1.3 in)
1919	10.9 mm (0.4 in)
1920	18.0 mm (0.7 in)
1921	15.7 mm (0.6 in)
1922	29.2 mm (1.1 in)
1923	20.8 mm (0.8 in)
1924	9.7 mm (0.38 in)
1925	16.5 mm (0.6 in)
1926	13.5 mm (0.5 in)
1927	17.5 mm (0.7 in)
1928	9.1 mm (0.36 in)
1929	25.4 mm (1.0 in)
1930	13.0 mm (0.5 in)
1931	20.8 mm (0.8 in)
1932	13.7 mm (0.5 in)
1933	22.6 mm (0.9 in)
1934	15.5 mm (0.6 in)
1935	12.7 mm (0.5 in)
1936	21.1 mm (0.8 in)
1937	22.9 mm (0.9 in)
1938	15.2 mm (0.6 in)
1939	14.5 mm (0.6 in)
1940	17.3 mm (0.7 in)
1941	21.8 mm (0.9 in)
1942	19.3 mm (0.8 in)
1943	31.8 mm (1.3 in)
1944	16.8 mm (0.7 in)
1945	17.0 mm (0.7 in)
1946	21.6 mm (0.9 in)
1947	17.8 mm (0.7 in)
1948	32.5 mm (1.3 in)
1949	10.9 mm (0.4 in)
1950	40.6 mm (1.6 in)
1951	9.9 mm (0.39 in)
1952	10.4 mm (0.4 in)
1953	20.6 mm (0.8 in)
1954	17.8 mm (0.7 in)
1955	22.9 mm (0.9 in)
1956	7.6 mm (0.30 in)
1957	16.0 mm (0.6 in)
1958	21.6 mm (0.9 in)
1959	15.2 mm (0.6 in)
1960	13.2 mm (0.5 in)
1961	25.1 mm (1.0 in)
1962	25.4 mm (1.0 in)
1963	18.8 mm (0.7 in)
1964	41.1 mm (1.6 in)
1965	11.9 mm (0.5 in)
1966	11.2 mm (0.4 in)
1967	15.2 mm (0.6 in)
1968	27.9 mm (1.1 in)
1969	15.5 mm (0.6 in)
1970	12.4 mm (0.5 in)
1971	19.1 mm (0.8 in)
1972	19.1 mm (0.8 in)
1973	22.9 mm (0.9 in)
1974	25.1 mm (1.0 in)
1975	17.0 mm (0.7 in)
1976	31.0 mm (1.2 in)
1977	18.0 mm (0.7 in)
1978	14.5 mm (0.6 in)
1979	12.2 mm (0.5 in)
1980	24.6 mm (1.0 in)
1981	14.5 mm (0.6 in)
1982	22.6 mm (0.9 in)
1983	47.0 mm (1.9 in)
1984	20.3 mm (0.8 in)
1985	13.2 mm (0.5 in)
1986	12.7 mm (0.5 in)
1987	16.8 mm (0.7 in)
1988	20.6 mm (0.8 in)
1989	10.9 mm (0.4 in)
1990	17.0 mm (0.7 in)
1991	26.2 mm (1.0 in)
1992	18.3 mm (0.7 in)
1993	25.4 mm (1.0 in)
1994	10.4 mm (0.4 in)
1995	25.4 mm (1.0 in)
1996	14.2 mm (0.6 in)

Wettest five days (Rx5day)

The wettest five days of the year at Challis, 1895 to 1996. The record is 72.1 mm (2.8 in) in 1964, marked on the chart; the median year is 27.9 mm (1.1 in).

Wettest five days (Rx5day) at Challis by year
Year	Wettest five days (Rx5day)
1895	10.2 mm (0.4 in)
1896	15.2 mm (0.6 in)
1897	12.7 mm (0.5 in)
1898	23.4 mm (0.9 in)
1899	28.5 mm (1.1 in)
1900	18.3 mm (0.7 in)
1901	25.4 mm (1.0 in)
1902	12.7 mm (0.5 in)
1914	38.2 mm (1.5 in)
1915	38.8 mm (1.5 in)
1916	10.2 mm (0.4 in)
1917	46.3 mm (1.8 in)
1918	19.8 mm (0.8 in)
1919	18.0 mm (0.7 in)
1920	19.0 mm (0.7 in)
1921	47.0 mm (1.9 in)
1922	46.5 mm (1.8 in)
1923	23.9 mm (0.9 in)
1924	18.1 mm (0.7 in)
1925	23.6 mm (0.9 in)
1926	15.3 mm (0.6 in)
1927	16.8 mm (0.7 in)
1928	16.2 mm (0.6 in)
1929	34.6 mm (1.4 in)
1930	26.5 mm (1.0 in)
1931	31.0 mm (1.2 in)
1932	29.2 mm (1.1 in)
1933	52.8 mm (2.1 in)
1934	21.6 mm (0.9 in)
1935	20.3 mm (0.8 in)
1936	46.7 mm (1.8 in)
1937	28.0 mm (1.1 in)
1938	27.9 mm (1.1 in)
1939	15.0 mm (0.6 in)
1940	30.3 mm (1.2 in)
1941	29.4 mm (1.2 in)
1942	35.0 mm (1.4 in)
1943	47.0 mm (1.9 in)
1944	34.3 mm (1.4 in)
1945	30.3 mm (1.2 in)
1946	26.5 mm (1.0 in)
1947	17.8 mm (0.7 in)
1948	54.4 mm (2.1 in)
1949	22.4 mm (0.9 in)
1950	45.2 mm (1.8 in)
1951	17.8 mm (0.7 in)
1952	22.4 mm (0.9 in)
1953	33.8 mm (1.3 in)
1954	31.3 mm (1.2 in)
1955	43.3 mm (1.7 in)
1956	15.3 mm (0.6 in)
1957	43.6 mm (1.7 in)
1958	26.7 mm (1.1 in)
1959	21.8 mm (0.9 in)
1960	23.9 mm (0.9 in)
1961	37.0 mm (1.5 in)
1962	29.7 mm (1.2 in)
1963	35.0 mm (1.4 in)
1964	72.1 mm (2.8 in)
1965	24.8 mm (1.0 in)
1966	21.4 mm (0.8 in)
1967	30.2 mm (1.2 in)
1968	55.6 mm (2.2 in)
1969	25.2 mm (1.0 in)
1970	24.1 mm (0.9 in)
1971	23.8 mm (0.9 in)
1972	24.2 mm (1.0 in)
1973	31.8 mm (1.3 in)
1974	25.1 mm (1.0 in)
1975	33.8 mm (1.3 in)
1976	33.1 mm (1.3 in)
1977	28.8 mm (1.1 in)
1978	22.9 mm (0.9 in)
1979	13.4 mm (0.5 in)
1980	38.1 mm (1.5 in)
1981	19.9 mm (0.8 in)
1982	35.5 mm (1.4 in)
1983	64.5 mm (2.5 in)
1984	28.7 mm (1.1 in)
1985	33.5 mm (1.3 in)
1986	20.3 mm (0.8 in)
1987	38.9 mm (1.5 in)
1988	20.6 mm (0.8 in)
1989	18.3 mm (0.7 in)
1990	35.6 mm (1.4 in)
1991	32.9 mm (1.3 in)
1992	30.3 mm (1.2 in)
1993	46.3 mm (1.8 in)
1994	22.2 mm (0.9 in)
1995	30.7 mm (1.2 in)
1996	17.5 mm (0.7 in)

Longest dry spell (CDD)

The longest dry spell of the year at Challis, 1895 to 1996. The record is 98 days in 1976, marked on the chart; the median year is 43 days.

Longest dry spell (CDD) at Challis by year
Year	Longest dry spell (CDD)
1895	25 days
1896	31 days
1897	35 days
1898	27 days
1899	50 days
1900	67 days
1901	31 days
1902	17 days
1914	52 days
1915	26 days
1916	49 days
1917	49 days
1918	53 days
1919	61 days
1920	28 days
1921	61 days
1922	57 days
1923	38 days
1924	43 days
1925	28 days
1926	35 days
1927	39 days
1928	43 days
1929	42 days
1930	40 days
1931	51 days
1932	39 days
1933	50 days
1934	33 days
1935	52 days
1936	59 days
1937	54 days
1938	57 days
1939	67 days
1940	50 days
1941	27 days
1942	71 days
1943	33 days
1944	38 days
1945	47 days
1946	26 days
1947	36 days
1948	48 days
1949	48 days
1950	33 days
1951	47 days
1952	71 days
1953	67 days
1954	42 days
1955	58 days
1956	40 days
1957	30 days
1958	58 days
1959	63 days
1960	61 days
1961	51 days
1962	51 days
1963	41 days
1964	59 days
1965	46 days
1966	40 days
1967	32 days
1968	25 days
1969	53 days
1970	36 days
1971	23 days
1972	30 days
1973	42 days
1974	50 days
1975	24 days
1976	98 days
1977	55 days
1978	69 days
1979	47 days
1980	48 days
1981	44 days
1982	24 days
1983	38 days
1984	35 days
1985	39 days
1986	28 days
1987	91 days
1988	55 days
1989	67 days
1990	36 days
1991	31 days
1992	44 days
1993	37 days
1994	39 days
1995	24 days
1996	27 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

68 years with a frost

Across 68 years with a frost, the median last spring frost at Challis falls on 2 June and the median first autumn frost on 17 September, which leaves a median of 110 days between them.

In 1961 to 1995 the median growing season was 115 days. That is 11 days more than in 1914 to 1949.

Fitted over all years, the growing season changes by +3.7 days per decade at this station.

Frost dates and growing season at Challis
Measure	Median, all years	Earliest period (1914 to 1949)	Recent period (1961 to 1995)	Recent against earliest	Fitted trend
Last spring frost	2 June	4 June	27 May	8 days earlier	-1.6 days per decade
First autumn frost	17 September	16 September	18 September	2 days later	+2.2 days per decade
Growing days	110 days	104 days	115 days	11 days more	+3.7 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

75 years, 1914 to 1995

A day with at least 17.8 mm (0.7 in) of rain is expected about once in 2 years. A day with at least 44.4 mm (1.7 in) of rain is expected about once in 100 years.

Rainfall return levels at Challis: the daily rain expected about once in a given number of years
Expected about once in	A day with at least	Note
2 years	17.8 mm (0.7 in)
5 years	24.5 mm (1.0 in)
10 years	29.1 mm (1.1 in)
25 years	35.1 mm (1.4 in)
50 years	39.7 mm (1.6 in)
100 years	44.4 mm (1.7 in)	Longer than the 75 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, 75 years of values from 1914 to 1995.

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: 47.0 mm (1.9 in) in 1983; 40.6 mm (1.6 in) in 1950; 35.6 mm (1.4 in) in 1915.

Station Changes

No change in the annual mean temperature of this station was found against its neighbours.

Download the Data

Data for Challis standing records by year: CSV or JSON. Field meanings are on the data page.
Data for Challis 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.

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