Idaho Falls 46 W Weather Records (USW00094143)

Record envelope, standing records and threshold days for Idaho Falls 46 W (USW00094143), Idaho, United States, with 73 years of record.

Key Facts for Idaho Falls 46 W

Idaho Falls 46 W (USW00094143) is a weather station in Idaho, United States at 43.53 latitude and -112.94 longitude, 1,505 m (4,938 ft) above sea level.
The station reports from 1954 to 2026, 73 years of record.
1,464 records set at Idaho Falls 46 W still stand.
Records are tracked for tmax, tmin, prcp, snow, snwd: an element needs 30 years of data to be eligible.
Idaho Falls 46 W tied a daily record high maximum temperature of 27.2 C (81.0 F) on 8 October 2026 (provisional).

Provisional Records

Records set in the last 60 days are provisional until they clear the revision window.

About the Station

Location: Idaho, United States, 43.53 latitude, -112.94 longitude.
Elevation: 1,505 m (4,938 ft).
Period of record: 1954 to 2026, 73 years.
Eligible elements: tmax, tmin, prcp, snow, snwd.

Daily Record Envelope and 2026

29 days at or beyond a record

The band shows the record high and record low for each calendar day at Idaho Falls 46 W. The lines show the 2026 daily maximum and minimum. 29 days in 2026 matched or passed a record. Temperatures are in degrees Celsius.

Daily record high and record low at Idaho Falls 46 W, with 2026 drawn through them
Month	Highest record high	Lowest record low	2026 highest maximum	2026 lowest minimum
Jan	12.8 C (55.0 F)	-40.0 C (-40.0 F)	7.2 C (45.0 F)	-20.0 C (-4.0 F)
Feb	15.6 C (60.1 F)	-37.8 C (-36.0 F)	13.9 C (57.0 F)	-23.9 C (-11.0 F)
Mar	26.1 C (79.0 F)	-33.3 C (-27.9 F)	26.1 C (79.0 F)	-8.9 C (16.0 F)
Apr	30.0 C (86.0 F)	-14.4 C (6.1 F)	24.4 C (75.9 F)	-11.1 C (12.0 F)
May	35.6 C (96.1 F)	-10.6 C (12.9 F)	31.1 C (88.0 F)	-7.2 C (19.0 F)
Jun	38.3 C (100.9 F)	-5.6 C (21.9 F)	34.4 C (93.9 F)	-2.8 C (27.0 F)
Jul	40.6 C (105.1 F)	-2.2 C (28.0 F)	40.6 C (105.1 F)	3.3 C (37.9 F)
Aug	38.9 C (102.0 F)	-4.4 C (24.1 F)	38.9 C (102.0 F)	-0.6 C (30.9 F)
Sep	37.2 C (99.0 F)	-11.1 C (12.0 F)	28.9 C (84.0 F)	-2.8 C (27.0 F)
Oct	31.7 C (89.1 F)	-22.2 C (-8.0 F)	28.3 C (82.9 F)	0.0 C (32.0 F)
Nov	21.1 C (70.0 F)	-31.1 C (-24.0 F)	n/a	n/a
Dec	13.9 C (57.0 F)	-43.9 C (-47.0 F)	n/a	n/a

Which Years Hold Standing Records

1,464 standing records

1,464 records at Idaho Falls 46 W still stand. 2015 holds the most, with 38.

Standing records at Idaho Falls 46 W by the year they were set
Year set	Standing records
1954	21
1955	32
1956	9
1957	11
1958	16
1959	14
1960	22
1961	17
1962	25
1963	19
1964	34
1965	22
1966	14
1967	7
1968	16
1969	21
1970	27
1971	17
1972	29
1973	14
1974	23
1975	28
1976	16
1977	22
1978	22
1979	20
1980	17
1981	19
1982	25
1983	28
1984	24
1985	36
1986	18
1987	35
1988	28
1989	20
1990	34
1991	16
1992	33
1993	25
1994	14
1995	27
1996	21
1997	17
1998	10
1999	16
2000	14
2001	11
2002	30
2003	33
2004	11
2005	7
2006	12
2007	12
2008	11
2009	12
2010	18
2011	11
2012	25
2013	21
2014	15
2015	38
2016	11
2017	10
2018	10
2019	12
2020	23
2021	19
2022	21
2023	28
2024	9
2025	24
2026	35

All-Time Record Progression

14 new records

14 all-time records were set at Idaho Falls 46 W between 16 February 1984 and 2 January 2006. Each dot is a new record.

When Idaho Falls 46 W set new all-time records
Date	Kind	Detail
1984-02-16	Record snow depth	Record snow depth 43.2 cm (17.0 in)
1985-02-01	Record low maximum temperature	Record low maximum temperature -22.8 C (-9.0 F)
1985-02-08	Record snow depth	Record snow depth 45.7 cm (18.0 in)
1985-02-09	Record snow depth	Record snow depth 50.8 cm (20.0 in)
1985-02-20	Record snow depth	Record snow depth 53.3 cm (21.0 in)
1985-03-03	Record snow depth	Record snow depth 61.0 cm (24.0 in)
1985-03-06	Record snow depth	Record snow depth 63.5 cm (25.0 in)
1993-02-15	Record snow depth	Record snow depth 68.6 cm (27.0 in)
1993-02-19	Record snow depth	Record snow depth 71.1 cm (28.0 in)
1993-02-23	Record snow depth	Record snow depth 76.2 cm (30.0 in)
2000-07-31	Record high maximum temperature	Record high maximum temperature 38.9 C (102.0 F)
2002-07-12	Record high maximum temperature	Record high maximum temperature 39.4 C (102.9 F)
2002-07-13	Record high maximum temperature	Record high maximum temperature 40.6 C (105.1 F)
2006-01-02	Record daily snowfall	Record daily snowfall 22.9 cm (9.0 in)

Wettest Day of Each Month

Jun: 41.7 mm (1.6 in)

The wettest day on record for each calendar month at Idaho Falls 46 W. The most was 41.7 mm (1.6 in) on 10 June 1969.

Record daily precipitation for each month at Idaho Falls 46 W
Month	Record daily precipitation (mm)	Date
Jan	24.4 mm (1.0 in)	2 January 2006
Feb	20.1 mm (0.8 in)	18 February 1986
Mar	24.1 mm (0.9 in)	22 March 2018
Apr	38.4 mm (1.5 in)	20 April 1981
May	35.8 mm (1.4 in)	12 May 2018
Jun	41.7 mm (1.6 in)	10 June 1969
Jul	31.8 mm (1.3 in)	23 July 1979
Aug	24.1 mm (0.9 in)	13 August 2022
Sep	39.4 mm (1.6 in)	18 September 1961
Oct	29.2 mm (1.1 in)	6 October 2011
Nov	18.0 mm (0.7 in)	29 November 1970
Dec	27.2 mm (1.1 in)	22 December 1964

Period of Record Coverage

1954 to 2026

73 years of record at Idaho Falls 46 W, 1954 to 2026. 2 years have data for under 90 percent of days and are left out of rankings: 1954, 2026.

Days with data per year at Idaho Falls 46 W
Year	Days with data	Share of year	Complete
1954	275	75%	No
1955	365	100%	Yes
1956	366	100%	Yes
1957	365	100%	Yes
1958	365	100%	Yes
1959	365	100%	Yes
1960	366	100%	Yes
1961	365	100%	Yes
1962	365	100%	Yes
1963	365	100%	Yes
1964	366	100%	Yes
1965	365	100%	Yes
1966	365	100%	Yes
1967	365	100%	Yes
1968	366	100%	Yes
1969	365	100%	Yes
1970	365	100%	Yes
1971	365	100%	Yes
1972	366	100%	Yes
1973	364	100%	Yes
1974	365	100%	Yes
1975	365	100%	Yes
1976	366	100%	Yes
1977	365	100%	Yes
1978	363	99%	Yes
1979	364	100%	Yes
1980	365	100%	Yes
1981	364	100%	Yes
1982	365	100%	Yes
1983	362	99%	Yes
1984	363	99%	Yes
1985	365	100%	Yes
1986	365	100%	Yes
1987	365	100%	Yes
1988	366	100%	Yes
1989	365	100%	Yes
1990	365	100%	Yes
1991	365	100%	Yes
1992	366	100%	Yes
1993	365	100%	Yes
1994	365	100%	Yes
1995	365	100%	Yes
1996	366	100%	Yes
1997	365	100%	Yes
1998	365	100%	Yes
1999	365	100%	Yes
2000	366	100%	Yes
2001	365	100%	Yes
2002	365	100%	Yes
2003	365	100%	Yes
2004	366	100%	Yes
2005	365	100%	Yes
2006	335	92%	Yes
2007	334	92%	Yes
2008	366	100%	Yes
2009	365	100%	Yes
2010	365	100%	Yes
2011	365	100%	Yes
2012	366	100%	Yes
2013	365	100%	Yes
2014	365	100%	Yes
2015	365	100%	Yes
2016	366	100%	Yes
2017	365	100%	Yes
2018	365	100%	Yes
2019	346	95%	Yes
2020	366	100%	Yes
2021	365	100%	Yes
2022	359	98%	Yes
2023	361	99%	Yes
2024	366	100%	Yes
2025	365	100%	Yes
2026	275	75%	No

Latest Records

Latest records at Idaho Falls 46 W
Date	Station	Record	Value	Beat old record by	Old record stood	Significance
8 October 2026	Idaho Falls 46 W, US	daily high max (Tie, Provisional)	27.2 C (81.0 F)	tie	47 years	5 of 100 (Routine)
7 October 2026	Idaho Falls 46 W, US	daily high max (Provisional)	28.3 C (82.9 F)	1.6 C (2.9 F)	47 years	23 of 100 (Routine)
17 September 2026	Idaho Falls 46 W, US	daily rain (Provisional)	37.3 mm (1.5 in)	24.3 mm (1.0 in)	1 year	47 of 100 (Notable)
28 August 2026	Idaho Falls 46 W, US	daily high min (Tie, Provisional)	15.0 C (59.0 F)	tie	68 years	6 of 100 (Routine)
22 August 2026	Idaho Falls 46 W, US	daily high min (Provisional)	17.2 C (63.0 F)	2.8 C (5.0 F)	23 years	20 of 100 (Routine)
21 August 2026	Idaho Falls 46 W, US	daily high max (Provisional)	37.2 C (99.0 F)	0.5 C (0.9 F)	16 years	13 of 100 (Routine)
20 August 2026	Idaho Falls 46 W, US	daily high max (Provisional)	37.8 C (100.0 F)	2.8 C (5.0 F)	23 years	19 of 100 (Routine)
15 August 2026	Idaho Falls 46 W, US	daily rain	8.4 mm (0.33 in)	5.1 mm (0.20 in)	47 years	20 of 100 (Routine)
7 August 2026	Idaho Falls 46 W, US	daily high max (Tie)	37.8 C (100.0 F)	tie	36 years	4 of 100 (Routine)
1 August 2026	Idaho Falls 46 W, US	monthly high max (Tie)	38.9 C (102.0 F)	tie	25 years	6 of 100 (Routine)
26 July 2026	Idaho Falls 46 W, US	daily high max	37.2 C (99.0 F)	0.5 C (0.9 F)	4 years	9 of 100 (Routine)
26 July 2026	Idaho Falls 46 W, US	daily high min (Tie)	16.1 C (61.0 F)	tie	72 years	7 of 100 (Routine)
25 July 2026	Idaho Falls 46 W, US	daily high max	37.8 C (100.0 F)	0.6 C (1.1 F)	48 years	22 of 100 (Routine)
24 July 2026	Idaho Falls 46 W, US	daily high max	38.9 C (102.0 F)	1.7 C (3.1 F)	48 years	25 of 100 (Routine)
21 July 2026	Idaho Falls 46 W, US	daily high min	18.9 C (66.0 F)	0.6 C (1.1 F)	12 years	11 of 100 (Routine)
18 July 2026	Idaho Falls 46 W, US	daily high min	17.8 C (64.0 F)	1.1 C (2.0 F)	48 years	24 of 100 (Routine)
15 July 2026	Idaho Falls 46 W, US	daily high min (Tie)	18.3 C (64.9 F)	tie	24 years	3 of 100 (Routine)
12 July 2026	Idaho Falls 46 W, US	all-time high max (Tie)	40.6 C (105.1 F)	tie	23 years	8 of 100 (Routine)
11 June 2026	Idaho Falls 46 W, US	daily low min	-2.8 C (27.0 F)	1.1 C (2.0 F)	24 years	16 of 100 (Routine)
10 June 2026	Idaho Falls 46 W, US	daily low min	-1.7 C (28.9 F)	0.6 C (1.1 F)	27 years	16 of 100 (Routine)

Climate Trend

68 complete years, 1955 to 2025

One stripe for each of 68 complete years at Idaho Falls 46 W, 1955 to 2025. Blue stripes are years cooler than the station's own mean of 5.7 C (42.3 F); red stripes are warmer. The coolest year was 1985, at 3.1 C (37.5 F), and the warmest was 2025, at 7.6 C (45.7 F). The strongest colour marks a difference of 2.7 C (4.9 F).

Annual mean temperature at Idaho Falls 46 W as warming stripes, 1955 to 2025
Year	Annual mean temperature	Difference from the station mean
1955	4.3 C	-1.44 C
1956	5.5 C	-0.20 C
1957	5.6 C	-0.19 C
1958	6.8 C	+1.09 C
1959	6.0 C	+0.28 C
1960	5.2 C	-0.51 C
1961	6.7 C	+0.96 C
1962	5.8 C	+0.04 C
1963	6.2 C	+0.50 C
1964	3.9 C	-1.83 C
1965	5.8 C	+0.05 C
1966	5.9 C	+0.19 C
1967	5.8 C	+0.09 C
1968	4.8 C	-0.96 C
1969	5.4 C	-0.30 C
1970	5.3 C	-0.42 C
1971	4.5 C	-1.25 C
1972	5.1 C	-0.64 C
1973	4.8 C	-0.96 C
1974	6.3 C	+0.56 C
1975	4.8 C	-0.94 C
1976	5.8 C	+0.03 C
1977	5.8 C	+0.09 C
1978	4.9 C	-0.86 C
1979	5.3 C	-0.46 C
1980	6.4 C	+0.66 C
1981	6.8 C	+1.01 C
1982	4.5 C	-1.21 C
1983	5.7 C	-0.02 C
1984	3.8 C	-1.97 C
1985	3.1 C	-2.66 C
1986	6.5 C	+0.71 C
1987	7.0 C	+1.26 C
1988	6.5 C	+0.72 C
1989	5.3 C	-0.48 C
1990	6.5 C	+0.72 C
1991	6.4 C	+0.61 C
1992	7.3 C	+1.54 C
1993	3.6 C	-2.12 C
1994	6.7 C	+0.99 C
1995	6.4 C	+0.61 C
1996	6.1 C	+0.37 C
1997	6.1 C	+0.34 C
1998	6.2 C	+0.45 C
1999	5.8 C	+0.05 C
2000	6.2 C	+0.49 C
2001	5.7 C	-0.03 C
2002	4.7 C	-1.01 C
2003	7.4 C	+1.68 C
2004	6.1 C	+0.40 C
2005	5.4 C	-0.36 C
2008	4.3 C	-1.40 C
2009	4.8 C	-0.91 C
2010	5.2 C	-0.59 C
2011	4.8 C	-0.99 C
2012	7.1 C	+1.37 C
2013	5.5 C	-0.23 C
2014	7.0 C	+1.27 C
2015	7.4 C	+1.65 C
2016	6.2 C	+0.47 C
2017	5.7 C	-0.04 C
2018	6.6 C	+0.89 C
2020	5.5 C	-0.21 C
2021	7.1 C	+1.37 C
2022	5.0 C	-0.78 C
2023	5.0 C	-0.70 C
2024	7.3 C	+1.54 C
2025	7.6 C	+1.89 C

The annual mean temperature here has risen by 0.12 C (0.01 to 0.24) per decade over 1955 to 2025. In Fahrenheit: 0.22 F (0.01 to 0.42) 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 Idaho Falls 46 W
Measure	Per decade (C)	Per decade (F)	Period	Complete years	Reading
Annual mean temperature	0.12 C (0.01 to 0.24) per decade	0.22 F (0.01 to 0.42) per decade	1955 to 2025	68	Rise
Mean daily maximum	0.13 C (0.00 to 0.27) per decade	0.24 F (0.00 to 0.48) per decade	1955 to 2025	68	Not clearly different from zero
Mean daily minimum	0.11 C (0.00 to 0.22) per decade	0.20 F (0.00 to 0.40) per decade	1955 to 2025	68	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

1954 to 2026

Yearly extremes at Idaho Falls 46 W: 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)	2002	36.7 C (98.1 F)	73
Coldest night (TNn)	-43.9 C (-47.0 F)	1983	-31.7 C (-25.1 F)	73
Wettest day (Rx1day)	41.7 mm (1.6 in)	1969	18.8 mm (0.7 in)	73
Wettest five days (Rx5day)	73.7 mm (2.9 in)	1995	33.5 mm (1.3 in)	73
Longest dry spell (CDD)	101 days	2003	40 days	73

Hottest day (TXx)

The hottest day of the year at Idaho Falls 46 W, 1954 to 2026. The record is 40.6 C (105.1 F) in 2002, marked on the chart; the median year is 36.7 C (98.1 F).

Hottest day (TXx) at Idaho Falls 46 W by year
Year	Hottest day (TXx)
1954	37.2 C (99.0 F)
1955	37.2 C (99.0 F)
1956	35.6 C (96.1 F)
1957	33.9 C (93.0 F)
1958	36.1 C (97.0 F)
1959	36.7 C (98.1 F)
1960	38.3 C (100.9 F)
1961	36.7 C (98.1 F)
1962	35.6 C (96.1 F)
1963	34.4 C (93.9 F)
1964	35.6 C (96.1 F)
1965	35.0 C (95.0 F)
1966	36.1 C (97.0 F)
1967	35.6 C (96.1 F)
1968	36.1 C (97.0 F)
1969	37.2 C (99.0 F)
1970	35.6 C (96.1 F)
1971	36.7 C (98.1 F)
1972	36.7 C (98.1 F)
1973	36.7 C (98.1 F)
1974	36.1 C (97.0 F)
1975	36.7 C (98.1 F)
1976	36.7 C (98.1 F)
1977	36.1 C (97.0 F)
1978	37.2 C (99.0 F)
1979	36.7 C (98.1 F)
1980	36.1 C (97.0 F)
1981	36.1 C (97.0 F)
1982	35.6 C (96.1 F)
1983	36.7 C (98.1 F)
1984	35.6 C (96.1 F)
1985	37.2 C (99.0 F)
1986	36.7 C (98.1 F)
1987	36.1 C (97.0 F)
1988	37.8 C (100.0 F)
1989	37.2 C (99.0 F)
1990	38.3 C (100.9 F)
1991	36.1 C (97.0 F)
1992	38.3 C (100.9 F)
1993	32.8 C (91.0 F)
1994	36.7 C (98.1 F)
1995	35.0 C (95.0 F)
1996	37.2 C (99.0 F)
1997	35.0 C (95.0 F)
1998	38.3 C (100.9 F)
1999	36.1 C (97.0 F)
2000	38.9 C (102.0 F)
2001	37.8 C (100.0 F)
2002	40.6 C (105.1 F)
2003	38.9 C (102.0 F)
2004	35.0 C (95.0 F)
2005	37.8 C (100.0 F)
2006	38.3 C (100.9 F)
2007	38.9 C (102.0 F)
2008	36.7 C (98.1 F)
2009	36.7 C (98.1 F)
2010	36.7 C (98.1 F)
2011	35.6 C (96.1 F)
2012	37.2 C (99.0 F)
2013	37.8 C (100.0 F)
2014	36.1 C (97.0 F)
2015	38.3 C (100.9 F)
2016	36.7 C (98.1 F)
2017	37.8 C (100.0 F)
2018	37.8 C (100.0 F)
2019	37.8 C (100.0 F)
2020	38.3 C (100.9 F)
2021	38.9 C (102.0 F)
2022	37.2 C (99.0 F)
2023	38.9 C (102.0 F)
2024	38.3 C (100.9 F)
2025	37.8 C (100.0 F)
2026	40.6 C (105.1 F)

Coldest night (TNn)

The coldest night of the year at Idaho Falls 46 W, 1954 to 2026. The record is -43.9 C (-47.0 F) in 1983, marked on the chart; the median year is -31.7 C (-25.1 F).

Coldest night (TNn) at Idaho Falls 46 W by year
Year	Coldest night (TNn)
1954	-27.2 C (-17.0 F)
1955	-31.1 C (-24.0 F)
1956	-34.4 C (-29.9 F)
1957	-33.9 C (-29.0 F)
1958	-26.1 C (-15.0 F)
1959	-35.0 C (-31.0 F)
1960	-35.6 C (-32.1 F)
1961	-25.0 C (-13.0 F)
1962	-40.0 C (-40.0 F)
1963	-37.2 C (-35.0 F)
1964	-36.1 C (-33.0 F)
1965	-23.3 C (-9.9 F)
1966	-25.6 C (-14.1 F)
1967	-30.6 C (-23.1 F)
1968	-33.9 C (-29.0 F)
1969	-25.6 C (-14.1 F)
1970	-30.6 C (-23.1 F)
1971	-33.3 C (-27.9 F)
1972	-40.0 C (-40.0 F)
1973	-35.6 C (-32.1 F)
1974	-33.9 C (-29.0 F)
1975	-32.2 C (-26.0 F)
1976	-27.8 C (-18.0 F)
1977	-34.4 C (-29.9 F)
1978	-38.3 C (-36.9 F)
1979	-36.1 C (-33.0 F)
1980	-32.8 C (-27.0 F)
1981	-31.7 C (-25.1 F)
1982	-35.6 C (-32.1 F)
1983	-43.9 C (-47.0 F)
1984	-36.7 C (-34.1 F)
1985	-37.8 C (-36.0 F)
1986	-26.7 C (-16.1 F)
1987	-27.2 C (-17.0 F)
1988	-33.3 C (-27.9 F)
1989	-32.8 C (-27.0 F)
1990	-38.9 C (-38.0 F)
1991	-28.9 C (-20.0 F)
1992	-33.3 C (-27.9 F)
1993	-32.8 C (-27.0 F)
1994	-25.0 C (-13.0 F)
1995	-25.6 C (-14.1 F)
1996	-35.0 C (-31.0 F)
1997	-24.4 C (-11.9 F)
1998	-33.3 C (-27.9 F)
1999	-26.1 C (-15.0 F)
2000	-25.0 C (-13.0 F)
2001	-28.9 C (-20.0 F)
2002	-29.4 C (-20.9 F)
2003	-23.3 C (-9.9 F)
2004	-32.8 C (-27.0 F)
2005	-34.4 C (-29.9 F)
2006	-26.1 C (-15.0 F)
2007	-26.7 C (-16.1 F)
2008	-34.4 C (-29.9 F)
2009	-31.7 C (-25.1 F)
2010	-32.2 C (-26.0 F)
2011	-31.1 C (-24.0 F)
2012	-24.4 C (-11.9 F)
2013	-33.9 C (-29.0 F)
2014	-31.1 C (-24.0 F)
2015	-31.1 C (-24.0 F)
2016	-31.1 C (-24.0 F)
2017	-33.3 C (-27.9 F)
2018	-26.7 C (-16.1 F)
2019	-27.8 C (-18.0 F)
2020	-28.9 C (-20.0 F)
2021	-21.7 C (-7.1 F)
2022	-30.6 C (-23.1 F)
2023	-34.4 C (-29.9 F)
2024	-35.6 C (-32.1 F)
2025	-27.2 C (-17.0 F)
2026	-23.9 C (-11.0 F)

Wettest day (Rx1day)

The wettest day of the year at Idaho Falls 46 W, 1954 to 2026. The record is 41.7 mm (1.6 in) in 1969, marked on the chart; the median year is 18.8 mm (0.7 in).

Wettest day (Rx1day) at Idaho Falls 46 W by year
Year	Wettest day (Rx1day)
1954	34.5 mm (1.4 in)
1955	9.9 mm (0.39 in)
1956	18.8 mm (0.7 in)
1957	19.3 mm (0.8 in)
1958	13.2 mm (0.5 in)
1959	20.8 mm (0.8 in)
1960	20.3 mm (0.8 in)
1961	39.4 mm (1.6 in)
1962	17.8 mm (0.7 in)
1963	29.0 mm (1.1 in)
1964	27.2 mm (1.1 in)
1965	20.1 mm (0.8 in)
1966	15.2 mm (0.6 in)
1967	21.3 mm (0.8 in)
1968	17.3 mm (0.7 in)
1969	41.7 mm (1.6 in)
1970	18.0 mm (0.7 in)
1971	21.6 mm (0.9 in)
1972	12.2 mm (0.5 in)
1973	18.5 mm (0.7 in)
1974	11.2 mm (0.4 in)
1975	17.0 mm (0.7 in)
1976	20.8 mm (0.8 in)
1977	17.8 mm (0.7 in)
1978	11.4 mm (0.4 in)
1979	31.8 mm (1.3 in)
1980	16.8 mm (0.7 in)
1981	38.4 mm (1.5 in)
1982	15.0 mm (0.6 in)
1983	18.0 mm (0.7 in)
1984	20.6 mm (0.8 in)
1985	16.5 mm (0.6 in)
1986	20.1 mm (0.8 in)
1987	24.1 mm (0.9 in)
1988	13.7 mm (0.5 in)
1989	23.6 mm (0.9 in)
1990	17.8 mm (0.7 in)
1991	22.6 mm (0.9 in)
1992	13.0 mm (0.5 in)
1993	20.8 mm (0.8 in)
1994	27.9 mm (1.1 in)
1995	39.4 mm (1.6 in)
1996	20.3 mm (0.8 in)
1997	14.0 mm (0.6 in)
1998	17.8 mm (0.7 in)
1999	14.2 mm (0.6 in)
2000	17.3 mm (0.7 in)
2001	14.0 mm (0.6 in)
2002	15.0 mm (0.6 in)
2003	12.2 mm (0.5 in)
2004	19.6 mm (0.8 in)
2005	16.8 mm (0.7 in)
2006	24.4 mm (1.0 in)
2007	19.8 mm (0.8 in)
2008	18.3 mm (0.7 in)
2009	26.4 mm (1.0 in)
2010	27.9 mm (1.1 in)
2011	29.2 mm (1.1 in)
2012	14.0 mm (0.6 in)
2013	6.1 mm (0.24 in)
2014	17.8 mm (0.7 in)
2015	15.7 mm (0.6 in)
2016	17.5 mm (0.7 in)
2017	30.0 mm (1.2 in)
2018	35.8 mm (1.4 in)
2019	16.8 mm (0.7 in)
2020	12.7 mm (0.5 in)
2021	26.4 mm (1.0 in)
2022	24.1 mm (0.9 in)
2023	19.8 mm (0.8 in)
2024	13.0 mm (0.5 in)
2025	20.8 mm (0.8 in)
2026	37.3 mm (1.5 in)

Wettest five days (Rx5day)

The wettest five days of the year at Idaho Falls 46 W, 1954 to 2026. The record is 73.7 mm (2.9 in) in 1995, marked on the chart; the median year is 33.5 mm (1.3 in).

Wettest five days (Rx5day) at Idaho Falls 46 W by year
Year	Wettest five days (Rx5day)
1954	49.7 mm (2.0 in)
1955	28.0 mm (1.1 in)
1956	34.0 mm (1.3 in)
1957	64.8 mm (2.6 in)
1958	20.9 mm (0.8 in)
1959	36.6 mm (1.4 in)
1960	35.1 mm (1.4 in)
1961	55.9 mm (2.2 in)
1962	48.4 mm (1.9 in)
1963	46.8 mm (1.8 in)
1964	53.3 mm (2.1 in)
1965	38.9 mm (1.5 in)
1966	21.3 mm (0.8 in)
1967	35.5 mm (1.4 in)
1968	68.7 mm (2.7 in)
1969	43.8 mm (1.7 in)
1970	32.7 mm (1.3 in)
1971	36.4 mm (1.4 in)
1972	21.6 mm (0.9 in)
1973	42.1 mm (1.7 in)
1974	20.6 mm (0.8 in)
1975	24.4 mm (1.0 in)
1976	33.4 mm (1.3 in)
1977	17.8 mm (0.7 in)
1978	21.8 mm (0.9 in)
1979	33.9 mm (1.3 in)
1980	25.1 mm (1.0 in)
1981	44.2 mm (1.7 in)
1982	29.2 mm (1.1 in)
1983	41.1 mm (1.6 in)
1984	51.4 mm (2.0 in)
1985	32.6 mm (1.3 in)
1986	46.8 mm (1.8 in)
1987	38.6 mm (1.5 in)
1988	29.7 mm (1.2 in)
1989	33.5 mm (1.3 in)
1990	24.9 mm (1.0 in)
1991	38.9 mm (1.5 in)
1992	17.4 mm (0.7 in)
1993	54.9 mm (2.2 in)
1994	28.5 mm (1.1 in)
1995	73.7 mm (2.9 in)
1996	22.9 mm (0.9 in)
1997	23.6 mm (0.9 in)
1998	34.3 mm (1.4 in)
1999	32.5 mm (1.3 in)
2000	19.6 mm (0.8 in)
2001	16.8 mm (0.7 in)
2002	15.0 mm (0.6 in)
2003	18.0 mm (0.7 in)
2004	24.9 mm (1.0 in)
2005	33.7 mm (1.3 in)
2006	38.6 mm (1.5 in)
2007	27.2 mm (1.1 in)
2008	34.9 mm (1.4 in)
2009	38.3 mm (1.5 in)
2010	39.1 mm (1.5 in)
2011	47.7 mm (1.9 in)
2012	18.9 mm (0.7 in)
2013	7.1 mm (0.28 in)
2014	50.4 mm (2.0 in)
2015	26.7 mm (1.1 in)
2016	33.3 mm (1.3 in)
2017	42.7 mm (1.7 in)
2018	55.4 mm (2.2 in)
2019	21.3 mm (0.8 in)
2020	18.1 mm (0.7 in)
2021	30.5 mm (1.2 in)
2022	24.1 mm (0.9 in)
2023	22.3 mm (0.9 in)
2024	30.0 mm (1.2 in)
2025	42.1 mm (1.7 in)
2026	37.3 mm (1.5 in)

Longest dry spell (CDD)

The longest dry spell of the year at Idaho Falls 46 W, 1954 to 2026. The record is 101 days in 2003, marked on the chart; the median year is 40 days.

Longest dry spell (CDD) at Idaho Falls 46 W by year
Year	Longest dry spell (CDD)
1954	32 days
1955	34 days
1956	43 days
1957	39 days
1958	57 days
1959	73 days
1960	51 days
1961	32 days
1962	54 days
1963	40 days
1964	61 days
1965	55 days
1966	38 days
1967	50 days
1968	47 days
1969	82 days
1970	33 days
1971	37 days
1972	50 days
1973	30 days
1974	56 days
1975	44 days
1976	63 days
1977	60 days
1978	35 days
1979	40 days
1980	46 days
1981	40 days
1982	28 days
1983	28 days
1984	45 days
1985	32 days
1986	31 days
1987	60 days
1988	76 days
1989	40 days
1990	46 days
1991	49 days
1992	45 days
1993	26 days
1994	62 days
1995	51 days
1996	35 days
1997	29 days
1998	27 days
1999	58 days
2000	38 days
2001	43 days
2002	51 days
2003	101 days
2004	39 days
2005	50 days
2006	45 days
2007	40 days
2008	81 days
2009	37 days
2010	26 days
2011	47 days
2012	40 days
2013	38 days
2014	31 days
2015	38 days
2016	27 days
2017	36 days
2018	54 days
2019	38 days
2020	28 days
2021	37 days
2022	62 days
2023	38 days
2024	76 days
2025	52 days
2026	36 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 Idaho Falls 46 W falls on 15 June and the median first autumn frost on 6 September, which leaves a median of 86 days between them.

In 1993 to 2025 the median growing season was 81 days. That is 9 days fewer than in 1955 to 1984.

Fitted over all years, the growing season changes by -1.4 days per decade at this station.

Frost dates and growing season at Idaho Falls 46 W
Measure	Median, all years	Earliest period (1955 to 1984)	Recent period (1993 to 2025)	Recent against earliest	Fitted trend
Last spring frost	15 June	10 June	17 June	7 days later	+0.9 days per decade
First autumn frost	6 September	5 September	5 September	no change	-0.5 days per decade
Growing days	86 days	90 days	81 days	9 days fewer	-1.4 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

67 years, 1955 to 2025

A day with at least 18.7 mm (0.7 in) of rain is expected about once in 2 years. A day with at least 43.4 mm (1.7 in) of rain is expected about once in 100 years.

Rainfall return levels at Idaho Falls 46 W: the daily rain expected about once in a given number of years
Expected about once in	A day with at least	Note
2 years	18.7 mm (0.7 in)
5 years	24.7 mm (1.0 in)
10 years	29.0 mm (1.1 in)
25 years	34.6 mm (1.4 in)
50 years	38.9 mm (1.5 in)
100 years	43.4 mm (1.7 in)	Longer than the 67 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, 67 years of values from 1955 to 2025.

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: 41.7 mm (1.6 in) in 1969; 39.4 mm (1.6 in) in 1961; 38.4 mm (1.5 in) in 1981.

Station Changes

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

Climate Twins

2010 to 2025 against 1961 to 1990

Over 2010 to 2025, Idaho Falls 46 W had a mean temperature of 6.2 C (43.2 F) and 206.3 mm (8.1 in) of rain a year. The 3 stations whose 1961 to 1990 climate was closest to that are Rock Springs (United States, 639 km away), Ridgeway 1 S (United States, 708 km away) and Tensleep 16SSE (United States, 450 km away).

Climate twins of Idaho Falls 46 W: stations whose 1961 to 1990 climate is closest to its 2010 to 2025 climate
Twin station	Country	Distance away	Mean temperature, 1961-1990	Rain a year, 1961-1990	Climate difference
Rock Springs	United States	639 km (397 mi)	6.5 C (43.7 F)	290.5 mm (11.4 in)	0.80
Ridgeway 1 S	United States	708 km (440 mi)	6.3 C (43.4 F)	310.7 mm (12.2 in)	0.90
Tensleep 16SSE	United States	450 km (280 mi)	5.8 C (42.4 F)	330.8 mm (13.0 in)	0.95

Twins are stations, not cities. A twin is one of the three stations at least 100 km away whose earlier climate is closest to this station's recent one, so a close match does not mean the two places look alike in other ways. A station move or a gap in a record can change that station's averages. The list describes past climate; it is not a forecast and does not say what caused any change. How twins are found, and a search for any station.

Download the Data

Data for Idaho Falls 46 W standing records by year: CSV or JSON. Field meanings are on the data page.
Data for Idaho Falls 46 W 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 2026-10-17. Last revised 17 October 2026 (2026-10-17).