Built 2026-10-19 (19 October 2026)

Lemhi Ridge Weather Records (USS0013E23S)

Record envelope, standing records and threshold days for Lemhi Ridge (USS0013E23S), Montana, United States, with 48 years of record.

Key Facts for Lemhi Ridge

  • Lemhi Ridge (USS0013E23S) is a weather station in Montana, United States at 44.99 latitude and -113.44 longitude, 2,469 m (8,100 ft) above sea level.
  • The station reports from 1979 to 2026, 48 years of record.
  • 1,464 records set at Lemhi Ridge still stand.
  • Records are tracked for tmax, tmin, prcp: an element needs 30 years of data to be eligible.
  • Lemhi Ridge set a daily record high minimum temperature of 6.8 C (44.2 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: Montana, United States, 44.99 latitude, -113.44 longitude.
  • Elevation: 2,469 m (8,100 ft).
  • Period of record: 1979 to 2026, 48 years.
  • Eligible elements: tmax, tmin, prcp.

Daily Record Envelope and 2026

19 days at or beyond a record
Daily record high and record low at Lemhi Ridge, with 2026 drawn through them The band shows the record high and record low for each calendar day at Lemhi Ridge. The lines show the 2026 daily maximum and minimum. 19 days in 2026 matched or passed a record. Temperatures are in degrees Celsius. -60-40-2002040 JanFebMarAprMayJunJulAugSepOctNovDec
The band shows the record high and record low for each calendar day at Lemhi Ridge. The lines show the 2026 daily maximum and minimum. 19 days in 2026 matched or passed a record. Temperatures are in degrees Celsius.
Daily record high and record low at Lemhi Ridge, with 2026 drawn through them
MonthHighest record highLowest record low2026 highest maximum2026 lowest minimum
Jan14.8 C (58.6 F)-31.4 C (-24.5 F)8.4 C (47.1 F)-19.0 C (-2.2 F)
Feb13.4 C (56.1 F)-33.3 C (-27.9 F)13.4 C (56.1 F)-16.2 C (2.8 F)
Mar15.8 C (60.4 F)-24.0 C (-11.2 F)15.8 C (60.4 F)-14.0 C (6.8 F)
Apr21.0 C (69.8 F)-18.0 C (-0.4 F)18.0 C (64.4 F)-9.1 C (15.6 F)
May24.9 C (76.8 F)-10.8 C (12.6 F)23.7 C (74.7 F)-7.1 C (19.2 F)
Jun29.9 C (85.8 F)-6.4 C (20.5 F)22.9 C (73.2 F)-1.8 C (28.8 F)
Jul30.9 C (87.6 F)-2.3 C (27.9 F)30.6 C (87.1 F)2.9 C (37.2 F)
Aug32.0 C (89.6 F)-6.1 C (21.0 F)29.7 C (85.5 F)1.2 C (34.2 F)
Sep30.4 C (86.7 F)-9.3 C (15.3 F)20.6 C (69.1 F)-2.5 C (27.5 F)
Oct23.6 C (74.5 F)-24.1 C (-11.4 F)21.0 C (69.8 F)-6.9 C (19.6 F)
Nov16.2 C (61.2 F)-26.6 C (-15.9 F)n/an/a
Dec10.8 C (51.4 F)-41.0 C (-41.8 F)n/an/a

Which Years Hold Standing Records

1,464 standing records
Standing records at Lemhi Ridge by the year they were set 1,464 records at Lemhi Ridge still stand. 1996 holds the most, with 66. 0204060801990: 571991: 591992: 481993: 631994: 581995: 491996: 661997: 341998: 161999: 402000: 262001: 232002: 352003: 442004: 272005: 342006: 382007: 262008: 532009: 532010: 252011: 202012: 302013: 372014: 322015: 502016: 412017: 362018: 252019: 332020: 372021: 562022: 402023: 332024: 422025: 402026: 381990199419982002200620102014201820222026
1,464 records at Lemhi Ridge still stand. 1996 holds the most, with 66.
Standing records at Lemhi Ridge by the year they were set
Year setStanding records
199057
199159
199248
199363
199458
199549
199666
199734
199816
199940
200026
200123
200235
200344
200427
200534
200638
200726
200853
200953
201025
201120
201230
201337
201432
201550
201641
201736
201825
201933
202037
202156
202240
202333
202442
202540
202638

Wettest Day of Each Month

May: 63.5 mm (2.5 in)
Record daily precipitation for each month at Lemhi Ridge The wettest day on record for each calendar month at Lemhi Ridge. The most was 63.5 mm (2.5 in) on 25 May 1980. 020406080 Jan: 22.9 mm (0.9 in), 31 January 1997 Jan Feb: 38.1 mm (1.5 in), 6 February 2020 Feb Mar: 27.9 mm (1.1 in), 26 March 1981 Mar Apr: 33.0 mm (1.3 in), 18 April 2007 Apr May: 63.5 mm (2.5 in), 25 May 1980 May Jun: 48.3 mm (1.9 in), 3 June 2001 Jun Jul: 25.4 mm (1.0 in), 17 July 1987 Jul Aug: 33.0 mm (1.3 in), 27 August 2025 Aug Sep: 30.5 mm (1.2 in), 5 September 2007 Sep Oct: 40.6 mm (1.6 in), 3 October 2013 Oct Nov: 30.5 mm (1.2 in), 26 November 1994 Nov Dec: 17.8 mm (0.7 in), 20 December 1996 Dec
The wettest day on record for each calendar month at Lemhi Ridge. The most was 63.5 mm (2.5 in) on 25 May 1980.
Record daily precipitation for each month at Lemhi Ridge
MonthRecord daily precipitation (mm)Date
Jan22.9 mm (0.9 in)31 January 1997
Feb38.1 mm (1.5 in)6 February 2020
Mar27.9 mm (1.1 in)26 March 1981
Apr33.0 mm (1.3 in)18 April 2007
May63.5 mm (2.5 in)25 May 1980
Jun48.3 mm (1.9 in)3 June 2001
Jul25.4 mm (1.0 in)17 July 1987
Aug33.0 mm (1.3 in)27 August 2025
Sep30.5 mm (1.2 in)5 September 2007
Oct40.6 mm (1.6 in)3 October 2013
Nov30.5 mm (1.2 in)26 November 1994
Dec17.8 mm (0.7 in)20 December 1996

Period of Record Coverage

1990 to 2026
Days with data per year at Lemhi Ridge 37 years of record at Lemhi Ridge, 1990 to 2026. 2 years have data for under 90 percent of days and are left out of rankings: 1990, 2026. 1990: 195 of 365 days1991: 365 of 365 days1992: 366 of 366 days1993: 360 of 365 days1994: 353 of 365 days1995: 364 of 365 days1996: 366 of 366 days1997: 365 of 365 days1998: 365 of 365 days1999: 365 of 365 days2000: 366 of 366 days2001: 365 of 365 days2002: 365 of 365 days2003: 365 of 365 days2004: 365 of 366 days2005: 365 of 365 days2006: 365 of 365 days2007: 365 of 365 days2008: 366 of 366 days2009: 365 of 365 days2010: 365 of 365 days2011: 365 of 365 days2012: 366 of 366 days2013: 365 of 365 days2014: 365 of 365 days2015: 365 of 365 days2016: 366 of 366 days2017: 365 of 365 days2018: 364 of 365 days2019: 365 of 365 days2020: 366 of 366 days2021: 364 of 365 days2022: 365 of 365 days2023: 365 of 365 days2024: 366 of 366 days2025: 365 of 365 days2026: 287 of 365 days19901995200020052010201520202025
37 years of record at Lemhi Ridge, 1990 to 2026. 2 years have data for under 90 percent of days and are left out of rankings: 1990, 2026.
Days with data per year at Lemhi Ridge
YearDays with dataShare of yearComplete
199019553%No
1991365100%Yes
1992366100%Yes
199336099%Yes
199435397%Yes
1995364100%Yes
1996366100%Yes
1997365100%Yes
1998365100%Yes
1999365100%Yes
2000366100%Yes
2001365100%Yes
2002365100%Yes
2003365100%Yes
2004365100%Yes
2005365100%Yes
2006365100%Yes
2007365100%Yes
2008366100%Yes
2009365100%Yes
2010365100%Yes
2011365100%Yes
2012366100%Yes
2013365100%Yes
2014365100%Yes
2015365100%Yes
2016366100%Yes
2017365100%Yes
2018364100%Yes
2019365100%Yes
2020366100%Yes
2021364100%Yes
2022365100%Yes
2023365100%Yes
2024366100%Yes
2025365100%Yes
202628779%No

Latest Records

20
Latest records at Lemhi Ridge
DateStationRecordValueBeat old record byOld record stoodSignificance
8 October 2026Lemhi Ridge, USdaily high min (Provisional)6.8 C (44.2 F)0.8 C (1.4 F)5 years5 of 100 (Routine)
6 October 2026Lemhi Ridge, USdaily high min (Provisional)7.3 C (45.1 F)0.2 C (0.4 F)23 years9 of 100 (Routine)
5 October 2026Lemhi Ridge, USdaily high min (Provisional)9.6 C (49.3 F)1.8 C (3.2 F)4 years7 of 100 (Routine)
4 October 2026Lemhi Ridge, USdaily high min (Provisional)7.9 C (46.2 F)1.3 C (2.3 F)4 years6 of 100 (Routine)
18 September 2026Lemhi Ridge, USdaily rain (Provisional)22.9 mm (0.9 in)10.2 mm (0.4 in)45 years20 of 100 (Routine)
21 August 2026Lemhi Ridge, USdaily high min (Provisional)15.3 C (59.5 F)2.2 C (4.0 F)16 years14 of 100 (Routine)
21 August 2026Lemhi Ridge, USdaily high max (Provisional)27.6 C (81.7 F)0.4 C (0.7 F)16 years8 of 100 (Routine)
20 August 2026Lemhi Ridge, USdaily high max (Provisional)27.2 C (81.0 F)0.5 C (0.9 F)7 years6 of 100 (Routine)
1 August 2026Lemhi Ridge, USdaily high max29.7 C (85.5 F)1.3 C (2.3 F)5 years7 of 100 (Routine)
26 July 2026Lemhi Ridge, USdaily high min15.0 C (59.0 F)1.1 C (2.0 F)4 years7 of 100 (Routine)
25 July 2026Lemhi Ridge, USdaily high max29.4 C (84.9 F)3.5 C (6.3 F)9 years13 of 100 (Routine)
25 July 2026Lemhi Ridge, USdaily high min16.3 C (61.3 F)3.2 C (5.8 F)4 years13 of 100 (Routine)
24 July 2026Lemhi Ridge, USdaily high min (Tie)13.4 C (56.1 F)tie8 years1 of 100 (Routine)
12 July 2026Lemhi Ridge, USdaily high min15.7 C (60.3 F)1.7 C (3.1 F)24 years14 of 100 (Routine)
12 July 2026Lemhi Ridge, USdaily high max30.6 C (87.1 F)0.1 C (0.2 F)24 years10 of 100 (Routine)
11 July 2026Lemhi Ridge, USdaily high max29.1 C (84.4 F)0.5 C (0.9 F)24 years11 of 100 (Routine)
29 June 2026Lemhi Ridge, USdaily rain33.0 mm (1.3 in)12.7 mm (0.5 in)33 years32 of 100 (Routine)
29 June 2026Lemhi Ridge, USdaily low max2.5 C (36.5 F)5.0 C (9.0 F)33 years21 of 100 (Routine)
28 June 2026Lemhi Ridge, USdaily rain45.7 mm (1.8 in)30.5 mm (1.2 in)33 years54 of 100 (Notable)
28 June 2026Lemhi Ridge, USdaily low max0.2 C (32.4 F)8.9 C (16.0 F)5 years19 of 100 (Routine)

Climate Trend

35 complete years, 1991 to 2025
Annual mean temperature at Lemhi Ridge as warming stripes, 1991 to 2025 One stripe for each of 35 complete years at Lemhi Ridge, 1991 to 2025. Blue stripes are years cooler than the station's own mean of 3.1 C (37.5 F); red stripes are warmer. The coolest year was 1993, at 1.1 C (34.0 F), and the warmest was 2015, at 4.7 C (40.4 F). The strongest colour marks a difference of 2.0 C (3.6 F). 1991: 2.0 C, -1.1 C from the station mean1992: 3.1 C, 0.0 C from the station mean1993: 1.1 C, -2.0 C from the station mean1994: 2.5 C, -0.5 C from the station mean1995: 1.6 C, -1.5 C from the station mean1996: 1.8 C, -1.3 C from the station mean1997: 2.3 C, -0.8 C from the station mean1998: 2.8 C, -0.3 C from the station mean1999: 3.0 C, -0.1 C from the station mean2000: 2.9 C, -0.2 C from the station mean2001: 3.4 C, +0.3 C from the station mean2002: 2.4 C, -0.7 C from the station mean2003: 3.5 C, +0.4 C from the station mean2004: 2.8 C, -0.3 C from the station mean2005: 3.0 C, -0.1 C from the station mean2006: 3.4 C, +0.3 C from the station mean2007: 3.7 C, +0.6 C from the station mean2008: 2.3 C, -0.8 C from the station mean2009: 2.6 C, -0.5 C from the station mean2010: 2.9 C, -0.2 C from the station mean2011: 2.5 C, -0.6 C from the station mean2012: 4.0 C, +1.0 C from the station mean2013: 3.4 C, +0.4 C from the station mean2014: 3.6 C, +0.5 C from the station mean2015: 4.7 C, +1.6 C from the station mean2016: 4.2 C, +1.1 C from the station mean2017: 3.9 C, +0.8 C from the station mean2018: 3.4 C, +0.3 C from the station mean2019: 2.6 C, -0.5 C from the station mean2020: 3.4 C, +0.4 C from the station mean2021: 3.8 C, +0.8 C from the station mean2022: 3.3 C, +0.2 C from the station mean2023: 3.4 C, +0.3 C from the station mean2024: 4.3 C, +1.2 C from the station mean2025: 4.6 C, +1.5 C from the station mean19911995200020052010201520202025
One stripe for each of 35 complete years at Lemhi Ridge, 1991 to 2025. Blue stripes are years cooler than the station's own mean of 3.1 C (37.5 F); red stripes are warmer. The coolest year was 1993, at 1.1 C (34.0 F), and the warmest was 2015, at 4.7 C (40.4 F). The strongest colour marks a difference of 2.0 C (3.6 F).
Annual mean temperature at Lemhi Ridge as warming stripes, 1991 to 2025
YearAnnual mean temperatureDifference from the station mean
19912.0 C-1.10 C
19923.1 C+0.04 C
19931.1 C-1.99 C
19942.5 C-0.54 C
19951.6 C-1.52 C
19961.8 C-1.27 C
19972.3 C-0.78 C
19982.8 C-0.28 C
19993.0 C-0.12 C
20002.9 C-0.17 C
20013.4 C+0.29 C
20022.4 C-0.70 C
20033.5 C+0.37 C
20042.8 C-0.33 C
20053.0 C-0.12 C
20063.4 C+0.31 C
20073.7 C+0.58 C
20082.3 C-0.76 C
20092.6 C-0.51 C
20102.9 C-0.22 C
20112.5 C-0.61 C
20124.0 C+0.96 C
20133.4 C+0.36 C
20143.6 C+0.52 C
20154.7 C+1.59 C
20164.2 C+1.11 C
20173.9 C+0.77 C
20183.4 C+0.27 C
20192.6 C-0.48 C
20203.4 C+0.36 C
20213.8 C+0.76 C
20223.3 C+0.18 C
20233.4 C+0.34 C
20244.3 C+1.22 C
20254.6 C+1.49 C

The annual mean temperature here has risen by 0.6 C (0.4 to 0.8) per decade over 1991 to 2025. In Fahrenheit: 1.0 F (0.7 to 1.4) 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 Lemhi Ridge
MeasurePer decade (C)Per decade (F)PeriodComplete yearsReading
Annual mean temperature0.6 C (0.4 to 0.8) per decade1.0 F (0.7 to 1.4) per decade1991 to 202535Rise
Mean daily maximum0.5 C (0.3 to 0.7) per decade0.9 F (0.5 to 1.3) per decade1991 to 202535Rise
Mean daily minimum0.6 C (0.4 to 0.9) per decade1.1 F (0.7 to 1.6) per decade1991 to 202535Rise

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

1979 to 2026
Yearly extremes at Lemhi Ridge: the record and the median year
MeasureRecordYear of the recordMedian yearYears with a value
Hottest day (TXx)32.0 C (89.6 F)199028.5 C (83.3 F)37
Coldest night (TNn)-41.0 C (-41.8 F)1990-25.4 C (-13.7 F)37
Wettest day (Rx1day)63.5 mm (2.5 in)198027.9 mm (1.1 in)48
Wettest five days (Rx5day)114.2 mm (4.5 in)202653.3 mm (2.1 in)48
Longest dry spell (CDD)77 days201723 days48

Hottest day (TXx)

Hottest day (TXx) at Lemhi Ridge by year The hottest day of the year at Lemhi Ridge, 1979 to 2026. The record is 32.0 C (89.6 F) in 1990, marked on the chart; the median year is 28.5 C (83.3 F). 242628303219801990200020102020Record: 32.0 C (89.6 F) in 1990
The hottest day of the year at Lemhi Ridge, 1979 to 2026. The record is 32.0 C (89.6 F) in 1990, marked on the chart; the median year is 28.5 C (83.3 F).
Hottest day (TXx) at Lemhi Ridge by year
YearHottest day (TXx)
1979n/a
1980n/a
1981n/a
1982n/a
1983n/a
1984n/a
1985n/a
1986n/a
1987n/a
1988n/a
1989n/a
199032.0 C (89.6 F)
199129.1 C (84.4 F)
199228.9 C (84.0 F)
199327.0 C (80.6 F)
199430.9 C (87.6 F)
199526.1 C (79.0 F)
199628.2 C (82.8 F)
199724.9 C (76.8 F)
199827.8 C (82.0 F)
199927.0 C (80.6 F)
200029.4 C (84.9 F)
200128.1 C (82.6 F)
200230.5 C (86.9 F)
200329.0 C (84.2 F)
200427.0 C (80.6 F)
200527.6 C (81.7 F)
200629.6 C (85.3 F)
200730.2 C (86.4 F)
200826.7 C (80.1 F)
200927.2 C (81.0 F)
201026.9 C (80.4 F)
201127.8 C (82.0 F)
201228.1 C (82.6 F)
201328.5 C (83.3 F)
201427.5 C (81.5 F)
201529.6 C (85.3 F)
201628.1 C (82.6 F)
201728.9 C (84.0 F)
201829.8 C (85.6 F)
201927.4 C (81.3 F)
202029.1 C (84.4 F)
202129.3 C (84.7 F)
202230.4 C (86.7 F)
202328.5 C (83.3 F)
202429.8 C (85.6 F)
202529.1 C (84.4 F)
202630.6 C (87.1 F)

Coldest night (TNn)

Coldest night (TNn) at Lemhi Ridge by year The coldest night of the year at Lemhi Ridge, 1979 to 2026. The record is -41.0 C (-41.8 F) in 1990, marked on the chart; the median year is -25.4 C (-13.7 F). -50-40-30-20-1019801990200020102020Record: -41.0 C (-41.8 F) in 1990
The coldest night of the year at Lemhi Ridge, 1979 to 2026. The record is -41.0 C (-41.8 F) in 1990, marked on the chart; the median year is -25.4 C (-13.7 F).
Coldest night (TNn) at Lemhi Ridge by year
YearColdest night (TNn)
1979n/a
1980n/a
1981n/a
1982n/a
1983n/a
1984n/a
1985n/a
1986n/a
1987n/a
1988n/a
1989n/a
1990-41.0 C (-41.8 F)
1991-28.2 C (-18.8 F)
1992-20.6 C (-5.1 F)
1993-30.8 C (-23.4 F)
1994-20.7 C (-5.3 F)
1995-27.9 C (-18.2 F)
1996-28.5 C (-19.3 F)
1997-31.4 C (-24.5 F)
1998-34.4 C (-29.9 F)
1999-18.6 C (-1.5 F)
2000-19.3 C (-2.7 F)
2001-21.2 C (-6.2 F)
2002-21.4 C (-6.5 F)
2003-25.2 C (-13.4 F)
2004-24.5 C (-12.1 F)
2005-24.1 C (-11.4 F)
2006-33.3 C (-27.9 F)
2007-29.7 C (-21.5 F)
2008-31.8 C (-25.2 F)
2009-30.2 C (-22.4 F)
2010-26.0 C (-14.8 F)
2011-24.5 C (-12.1 F)
2012-19.5 C (-3.1 F)
2013-30.0 C (-22.0 F)
2014-32.5 C (-26.5 F)
2015-22.8 C (-9.0 F)
2016-23.8 C (-10.8 F)
2017-24.0 C (-11.2 F)
2018-25.3 C (-13.5 F)
2019-24.1 C (-11.4 F)
2020-20.4 C (-4.7 F)
2021-26.1 C (-15.0 F)
2022-35.4 C (-31.7 F)
2023-29.9 C (-21.8 F)
2024-26.4 C (-15.5 F)
2025-25.4 C (-13.7 F)
2026-19.0 C (-2.2 F)

Wettest day (Rx1day)

Wettest day (Rx1day) at Lemhi Ridge by year The wettest day of the year at Lemhi Ridge, 1979 to 2026. The record is 63.5 mm (2.5 in) in 1980, marked on the chart; the median year is 27.9 mm (1.1 in). 02040608019801990200020102020Record: 63.5 mm (2.5 in) in 1980
The wettest day of the year at Lemhi Ridge, 1979 to 2026. The record is 63.5 mm (2.5 in) in 1980, marked on the chart; the median year is 27.9 mm (1.1 in).
Wettest day (Rx1day) at Lemhi Ridge by year
YearWettest day (Rx1day)
197920.3 mm (0.8 in)
198063.5 mm (2.5 in)
198135.6 mm (1.4 in)
198227.9 mm (1.1 in)
198320.3 mm (0.8 in)
198430.5 mm (1.2 in)
198527.9 mm (1.1 in)
198627.9 mm (1.1 in)
198725.4 mm (1.0 in)
198825.4 mm (1.0 in)
198920.3 mm (0.8 in)
199025.4 mm (1.0 in)
199127.9 mm (1.1 in)
199245.7 mm (1.8 in)
199320.3 mm (0.8 in)
199430.5 mm (1.2 in)
199545.7 mm (1.8 in)
199627.9 mm (1.1 in)
199733.0 mm (1.3 in)
199825.4 mm (1.0 in)
199917.8 mm (0.7 in)
200025.4 mm (1.0 in)
200148.3 mm (1.9 in)
200230.5 mm (1.2 in)
200327.9 mm (1.1 in)
200425.4 mm (1.0 in)
200525.4 mm (1.0 in)
200630.5 mm (1.2 in)
200740.6 mm (1.6 in)
200825.4 mm (1.0 in)
200930.5 mm (1.2 in)
201043.2 mm (1.7 in)
201125.4 mm (1.0 in)
201220.3 mm (0.8 in)
201340.6 mm (1.6 in)
201430.5 mm (1.2 in)
201522.9 mm (0.9 in)
201617.8 mm (0.7 in)
201735.6 mm (1.4 in)
201827.9 mm (1.1 in)
201920.3 mm (0.8 in)
202038.1 mm (1.5 in)
202135.6 mm (1.4 in)
202225.4 mm (1.0 in)
202330.5 mm (1.2 in)
202417.8 mm (0.7 in)
202535.6 mm (1.4 in)
202645.7 mm (1.8 in)

Wettest five days (Rx5day)

Wettest five days (Rx5day) at Lemhi Ridge by year The wettest five days of the year at Lemhi Ridge, 1979 to 2026. The record is 114.2 mm (4.5 in) in 2026, marked on the chart; the median year is 53.3 mm (2.1 in). 2040608010012019801990200020102020Record: 114.2 mm (4.5 in) in 2026
The wettest five days of the year at Lemhi Ridge, 1979 to 2026. The record is 114.2 mm (4.5 in) in 2026, marked on the chart; the median year is 53.3 mm (2.1 in).
Wettest five days (Rx5day) at Lemhi Ridge by year
YearWettest five days (Rx5day)
197950.8 mm (2.0 in)
1980106.7 mm (4.2 in)
198145.7 mm (1.8 in)
198253.2 mm (2.1 in)
198345.6 mm (1.8 in)
198453.4 mm (2.1 in)
198558.3 mm (2.3 in)
198673.7 mm (2.9 in)
198760.9 mm (2.4 in)
198840.7 mm (1.6 in)
198938.0 mm (1.5 in)
199050.9 mm (2.0 in)
199150.9 mm (2.0 in)
199263.5 mm (2.5 in)
199353.3 mm (2.1 in)
199450.8 mm (2.0 in)
199576.1 mm (3.0 in)
199640.6 mm (1.6 in)
199768.5 mm (2.7 in)
199858.4 mm (2.3 in)
199943.2 mm (1.7 in)
200055.9 mm (2.2 in)
200183.8 mm (3.3 in)
200255.8 mm (2.2 in)
200348.4 mm (1.9 in)
200445.7 mm (1.8 in)
200548.3 mm (1.9 in)
200650.7 mm (2.0 in)
200768.5 mm (2.7 in)
200845.8 mm (1.8 in)
200953.3 mm (2.1 in)
201061.0 mm (2.4 in)
201161.0 mm (2.4 in)
201253.3 mm (2.1 in)
201361.0 mm (2.4 in)
201450.9 mm (2.0 in)
201543.3 mm (1.7 in)
201638.1 mm (1.5 in)
201776.2 mm (3.0 in)
201863.4 mm (2.5 in)
201938.1 mm (1.5 in)
202083.8 mm (3.3 in)
202166.0 mm (2.6 in)
202258.4 mm (2.3 in)
202358.4 mm (2.3 in)
202438.1 mm (1.5 in)
202548.2 mm (1.9 in)
2026114.2 mm (4.5 in)

Longest dry spell (CDD)

Longest dry spell (CDD) at Lemhi Ridge by year The longest dry spell of the year at Lemhi Ridge, 1979 to 2026. The record is 77 days in 2017, marked on the chart; the median year is 23 days. 02040608019801990200020102020Record: 77 days in 2017
The longest dry spell of the year at Lemhi Ridge, 1979 to 2026. The record is 77 days in 2017, marked on the chart; the median year is 23 days.
Longest dry spell (CDD) at Lemhi Ridge by year
YearLongest dry spell (CDD)
197933 days
198023 days
198151 days
198220 days
198318 days
198417 days
198521 days
198630 days
198743 days
198836 days
198917 days
199031 days
199125 days
199232 days
199333 days
199420 days
199520 days
199637 days
199710 days
199818 days
199939 days
200030 days
200136 days
200222 days
200330 days
200419 days
200532 days
200631 days
200722 days
200816 days
200912 days
201021 days
201119 days
201225 days
201324 days
201416 days
201521 days
201621 days
201777 days
201822 days
201917 days
202033 days
202123 days
202229 days
202315 days
202428 days
202515 days
202629 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 Lemhi Ridge falls on 21 June and the median first autumn frost on 7 September, which leaves a median of 79 days between them.

Fitted over all years, the growing season changes by +21.0 days per decade at this station.

Frost dates and growing season at Lemhi Ridge
MeasureMedian, all yearsEarliest periodRecent period (1996 to 2025)Recent against earliestFitted trend
Last spring frost21 Junen/a19 Junen/a-3.3 days per decade
First autumn frost7 Septembern/a8 Septembern/a+17.6 days per decade
Growing days79 daysn/a83 daysn/a+21.0 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

46 years, 1980 to 2025

A day with at least 28.1 mm (1.1 in) of rain is expected about once in 2 years. A day with at least 62.3 mm (2.5 in) of rain is expected about once in 100 years.

Rainfall return levels at Lemhi Ridge: the daily rain expected about once in a given number of years
Expected about once inA day with at leastNote
2 years28.1 mm (1.1 in)
5 years36.0 mm (1.4 in)
10 years41.6 mm (1.6 in)
25 years49.4 mm (1.9 in)
50 years55.7 mm (2.2 in)Longer than the 46 years of record
100 years62.3 mm (2.5 in)Longer than the 46 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, 46 years of values from 1980 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: 63.5 mm (2.5 in) in 1980; 48.3 mm (1.9 in) in 2001; 45.7 mm (1.8 in) in 1992.

Download the Data

  • Data for Lemhi Ridge standing records by year: CSV or JSON. Field meanings are on the data page.
  • Data for Lemhi Ridge 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 . Last revised (2026-10-17).