Alamo Dam Weather Records (USC00020100)
Record envelope, standing records and threshold days for Alamo Dam (USC00020100), Arizona, United States, with 52 years of record.
Key Facts for Alamo Dam
- Alamo Dam (USC00020100) is a weather station in Arizona, United States at 34.23 latitude and -113.58 longitude, 393 m (1,290 ft) above sea level.
- The station reports from 1975 to 2026, 52 years of record.
- 1,464 records set at Alamo Dam still stand.
- Records are tracked for tmax, tmin, prcp, snow, snwd: an element needs 30 years of data to be eligible.
- Alamo Dam set a daily record high minimum temperature of 28.9 C (84.0 F) on 30 August 2026 (provisional).
Provisional Records
Records set in the last 60 days are provisional until they clear the revision window.
About the Station
- Location: Arizona, United States, 34.23 latitude, -113.58 longitude.
- Elevation: 393 m (1,290 ft).
- Period of record: 1975 to 2026, 52 years.
- Eligible elements: tmax, tmin, prcp, snow, snwd.
Daily Record Envelope and 2026
6 days at or beyond a record| Month | Highest record high | Lowest record low | 2026 highest maximum | 2026 lowest minimum |
|---|---|---|---|---|
| Jan | 28.9 C (84.0 F) | -7.2 C (19.0 F) | 25.6 C (78.1 F) | -1.1 C (30.0 F) |
| Feb | 32.2 C (90.0 F) | -6.1 C (21.0 F) | 32.2 C (90.0 F) | 1.7 C (35.1 F) |
| Mar | 38.9 C (102.0 F) | -3.3 C (26.1 F) | 32.8 C (91.0 F) | 10.6 C (51.1 F) |
| Apr | 41.7 C (107.1 F) | -1.1 C (30.0 F) | 35.6 C (96.1 F) | 8.9 C (48.0 F) |
| May | 45.6 C (114.1 F) | 0.6 C (33.1 F) | 42.8 C (109.0 F) | 11.7 C (53.1 F) |
| Jun | 50.6 C (123.1 F) | 6.1 C (43.0 F) | 44.4 C (111.9 F) | 16.7 C (62.1 F) |
| Jul | 51.1 C (124.0 F) | 14.4 C (57.9 F) | 47.2 C (117.0 F) | 18.9 C (66.0 F) |
| Aug | 49.4 C (120.9 F) | 15.0 C (59.0 F) | 47.2 C (117.0 F) | 22.2 C (72.0 F) |
| Sep | 47.8 C (118.0 F) | 2.8 C (37.0 F) | n/a | n/a |
| Oct | 43.9 C (111.0 F) | -1.7 C (28.9 F) | n/a | n/a |
| Nov | 36.7 C (98.1 F) | -3.9 C (25.0 F) | n/a | n/a |
| Dec | 28.9 C (84.0 F) | -7.2 C (19.0 F) | n/a | n/a |
Which Years Hold Standing Records
1,464 standing records| Year set | Standing records |
|---|---|
| 1975 | 10 |
| 1976 | 26 |
| 1977 | 34 |
| 1978 | 34 |
| 1979 | 37 |
| 1980 | 38 |
| 1981 | 31 |
| 1982 | 35 |
| 1983 | 23 |
| 1984 | 25 |
| 1985 | 37 |
| 1986 | 34 |
| 1987 | 30 |
| 1988 | 26 |
| 1989 | 33 |
| 1990 | 37 |
| 1991 | 34 |
| 1992 | 17 |
| 1993 | 14 |
| 1994 | 27 |
| 1995 | 37 |
| 1996 | 34 |
| 1997 | 24 |
| 1998 | 27 |
| 1999 | 34 |
| 2000 | 43 |
| 2001 | 23 |
| 2002 | 23 |
| 2003 | 27 |
| 2004 | 22 |
| 2005 | 18 |
| 2006 | 24 |
| 2007 | 36 |
| 2008 | 12 |
| 2009 | 24 |
| 2010 | 28 |
| 2011 | 36 |
| 2012 | 21 |
| 2013 | 26 |
| 2014 | 16 |
| 2015 | 35 |
| 2016 | 24 |
| 2017 | 24 |
| 2018 | 20 |
| 2019 | 66 |
| 2020 | 43 |
| 2021 | 27 |
| 2022 | 23 |
| 2023 | 20 |
| 2024 | 31 |
| 2025 | 21 |
| 2026 | 13 |
All-Time Record Progression
3 new records| Date | Kind | Detail |
|---|---|---|
| 2006-07-23 | Record high minimum temperature | Record high minimum temperature 33.9 C (93.0 F) |
| 2015-01-01 | Record low maximum temperature | Record low maximum temperature 1.7 C (35.1 F) |
| 2022-09-12 | Record daily precipitation | Record daily precipitation 64.0 mm (2.5 in) |
Wettest Day of Each Month
Sep: 64.0 mm (2.5 in)| Month | Record daily precipitation (mm) | Date |
|---|---|---|
| Jan | 49.5 mm (1.9 in) | 15 January 2019 |
| Feb | 42.2 mm (1.7 in) | 9 February 1993 |
| Mar | 32.8 mm (1.3 in) | 4 March 1983 |
| Apr | 22.4 mm (0.9 in) | 19 April 1995 |
| May | 15.0 mm (0.6 in) | 7 May 2025 |
| Jun | 16.5 mm (0.6 in) | 22 June 2000 |
| Jul | 36.3 mm (1.4 in) | 14 July 2012 |
| Aug | 63.5 mm (2.5 in) | 14 August 1984 |
| Sep | 64.0 mm (2.5 in) | 12 September 2022 |
| Oct | 58.4 mm (2.3 in) | 21 October 2004 |
| Nov | 45.7 mm (1.8 in) | 27 November 2008 |
| Dec | 31.8 mm (1.3 in) | 17 December 1978 |
Period of Record Coverage
1975 to 2026| Year | Days with data | Share of year | Complete |
|---|---|---|---|
| 1975 | 173 | 47% | No |
| 1976 | 366 | 100% | Yes |
| 1977 | 360 | 99% | Yes |
| 1978 | 365 | 100% | Yes |
| 1979 | 365 | 100% | Yes |
| 1980 | 366 | 100% | Yes |
| 1981 | 364 | 100% | Yes |
| 1982 | 364 | 100% | Yes |
| 1983 | 364 | 100% | Yes |
| 1984 | 356 | 97% | Yes |
| 1985 | 364 | 100% | Yes |
| 1986 | 365 | 100% | Yes |
| 1987 | 365 | 100% | Yes |
| 1988 | 366 | 100% | Yes |
| 1989 | 365 | 100% | Yes |
| 1990 | 364 | 100% | Yes |
| 1991 | 364 | 100% | Yes |
| 1992 | 365 | 100% | Yes |
| 1993 | 364 | 100% | Yes |
| 1994 | 365 | 100% | Yes |
| 1995 | 365 | 100% | Yes |
| 1996 | 366 | 100% | Yes |
| 1997 | 364 | 100% | Yes |
| 1998 | 365 | 100% | Yes |
| 1999 | 365 | 100% | Yes |
| 2000 | 366 | 100% | Yes |
| 2001 | 364 | 100% | Yes |
| 2002 | 365 | 100% | Yes |
| 2003 | 363 | 99% | Yes |
| 2004 | 364 | 99% | Yes |
| 2005 | 365 | 100% | Yes |
| 2006 | 362 | 99% | Yes |
| 2007 | 359 | 98% | Yes |
| 2008 | 354 | 97% | Yes |
| 2009 | 337 | 92% | Yes |
| 2010 | 348 | 95% | Yes |
| 2011 | 342 | 94% | Yes |
| 2012 | 339 | 93% | Yes |
| 2013 | 351 | 96% | Yes |
| 2014 | 349 | 96% | Yes |
| 2015 | 340 | 93% | Yes |
| 2016 | 338 | 92% | Yes |
| 2017 | 319 | 87% | No |
| 2018 | 343 | 94% | Yes |
| 2019 | 328 | 90% | No |
| 2020 | 357 | 98% | Yes |
| 2021 | 336 | 92% | Yes |
| 2022 | 344 | 94% | Yes |
| 2023 | 348 | 95% | Yes |
| 2024 | 360 | 98% | Yes |
| 2025 | 349 | 96% | Yes |
| 2026 | 200 | 55% | No |
Latest Records
20| Date | Station | Record | Value | Beat old record by | Old record stood | Significance |
|---|---|---|---|---|---|---|
| 30 August 2026 | Alamo Dam, US | daily high min (Provisional) | 28.9 C (84.0 F) | 0.6 C (1.1 F) | 3 years | 6 of 100 (Routine) |
| 28 August 2026 | Alamo Dam, US | daily high max (Provisional) | 46.7 C (116.1 F) | 0.6 C (1.1 F) | 44 years | 19 of 100 (Routine) |
| 27 August 2026 | Alamo Dam, US | daily high min (Tie, Provisional) | 28.3 C (82.9 F) | tie | 44 years | 4 of 100 (Routine) |
| 5 August 2026 | Alamo Dam, US | daily high min | 30.6 C (87.1 F) | 0.6 C (1.1 F) | 21 years | 12 of 100 (Routine) |
| 3 August 2026 | Alamo Dam, US | daily high min | 30.6 C (87.1 F) | 0.6 C (1.1 F) | 1 year | 6 of 100 (Routine) |
| 3 August 2026 | Alamo Dam, US | daily high max (Tie) | 46.7 C (116.1 F) | tie | 31 years | 3 of 100 (Routine) |
| 30 July 2026 | Alamo Dam, US | daily high min | 31.7 C (89.1 F) | 1.1 C (2.0 F) | 3 years | 8 of 100 (Routine) |
| 29 July 2026 | Alamo Dam, US | daily high min | 32.2 C (90.0 F) | 1.1 C (2.0 F) | 45 years | 21 of 100 (Routine) |
| 25 July 2026 | Alamo Dam, US | daily high min (Tie) | 31.1 C (88.0 F) | tie | 1 year | 1 of 100 (Routine) |
| 18 July 2026 | Alamo Dam, US | daily low max | 35.6 C (96.1 F) | 0.5 C (0.9 F) | 36 years | 16 of 100 (Routine) |
| 16 June 2026 | Alamo Dam, US | daily high min | 26.7 C (80.1 F) | 0.6 C (1.1 F) | 32 years | 15 of 100 (Routine) |
| 15 June 2026 | Alamo Dam, US | daily high min | 26.1 C (79.0 F) | 1.7 C (3.1 F) | 25 years | 16 of 100 (Routine) |
| 13 June 2026 | Alamo Dam, US | daily high min (Tie) | 25.6 C (78.1 F) | tie | 8 years | 1 of 100 (Routine) |
| 11 April 2026 | Alamo Dam, US | daily high min | 17.8 C (64.0 F) | 1.1 C (2.0 F) | 36 years | 19 of 100 (Routine) |
| 10 April 2026 | Alamo Dam, US | daily high min | 17.2 C (63.0 F) | 1.1 C (2.0 F) | 25 years | 15 of 100 (Routine) |
| 4 April 2026 | Alamo Dam, US | daily high min (Tie) | 15.6 C (60.1 F) | tie | 20 years | 2 of 100 (Routine) |
| 1 March 2026 | Alamo Dam, US | daily high max | 32.8 C (91.0 F) | 1.1 C (2.0 F) | 40 years | 19 of 100 (Routine) |
| 28 February 2026 | Alamo Dam, US | daily high min | 12.2 C (54.0 F) | 0.5 C (0.9 F) | 48 years | 20 of 100 (Routine) |
| 28 February 2026 | Alamo Dam, US | monthly high max (Tie) | 32.2 C (90.0 F) | tie | 10 years | 4 of 100 (Routine) |
| 27 February 2026 | Alamo Dam, US | daily high max (Tie) | 31.1 C (88.0 F) | tie | 40 years | 4 of 100 (Routine) |
Climate Trend
42 complete years, 1976 to 2025| Year | Annual mean temperature | Difference from the station mean |
|---|---|---|
| 1976 | 21.2 C | -0.46 C |
| 1977 | 21.4 C | -0.19 C |
| 1978 | 21.4 C | -0.20 C |
| 1979 | 20.4 C | -1.19 C |
| 1980 | 21.7 C | +0.08 C |
| 1981 | 22.7 C | +1.03 C |
| 1982 | 20.7 C | -0.89 C |
| 1983 | 21.1 C | -0.54 C |
| 1984 | 21.6 C | -0.08 C |
| 1985 | 21.1 C | -0.55 C |
| 1986 | 21.4 C | -0.26 C |
| 1987 | 21.2 C | -0.48 C |
| 1988 | 21.5 C | -0.16 C |
| 1989 | 22.0 C | +0.41 C |
| 1990 | 20.9 C | -0.69 C |
| 1991 | 21.1 C | -0.54 C |
| 1992 | 21.3 C | -0.32 C |
| 1993 | 21.2 C | -0.42 C |
| 1994 | 21.7 C | +0.03 C |
| 1995 | 21.7 C | +0.11 C |
| 1996 | 22.6 C | +0.96 C |
| 1997 | 22.1 C | +0.45 C |
| 1998 | 20.9 C | -0.71 C |
| 1999 | 21.9 C | +0.27 C |
| 2000 | 22.4 C | +0.73 C |
| 2001 | 22.0 C | +0.34 C |
| 2002 | 21.7 C | +0.06 C |
| 2003 | 22.1 C | +0.45 C |
| 2004 | 21.7 C | +0.10 C |
| 2005 | 21.4 C | -0.21 C |
| 2007 | 22.1 C | +0.50 C |
| 2008 | 22.0 C | +0.37 C |
| 2010 | 21.3 C | -0.38 C |
| 2011 | 20.9 C | -0.76 C |
| 2013 | 21.7 C | +0.11 C |
| 2014 | 22.5 C | +0.88 C |
| 2015 | 22.0 C | +0.32 C |
| 2020 | 21.6 C | +0.01 C |
| 2022 | 21.7 C | +0.05 C |
| 2023 | 21.7 C | +0.10 C |
| 2024 | 22.7 C | +1.04 C |
| 2025 | 22.4 C | +0.77 C |
The annual mean temperature here has risen by 0.2 C (0.1 to 0.3) per decade over 1976 to 2025. In Fahrenheit: 0.3 F (0.1 to 0.5) per decade. The slope is a straight line fitted to 42 complete years; the brackets give its 95 percent interval.
| Measure | Per decade (C) | Per decade (F) | Period | Complete years | Reading |
|---|---|---|---|---|---|
| Annual mean temperature | 0.2 C (0.1 to 0.3) per decade | 0.3 F (0.1 to 0.5) per decade | 1976 to 2025 | 42 | Rise |
| Mean daily maximum | 0.3 C (0.2 to 0.5) per decade | 0.6 F (0.3 to 0.9) per decade | 1976 to 2025 | 42 | Rise |
| Mean daily minimum | -0.01 C (-0.15 to 0.13) per decade | -0.01 F (-0.27 to 0.24) per decade | 1976 to 2025 | 42 | 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
1975 to 2026| Measure | Record | Year of the record | Median year | Years with a value |
|---|---|---|---|---|
| Hottest day (TXx) | 51.1 C (124.0 F) | 1995 | 47.2 C (117.0 F) | 52 |
| Coldest night (TNn) | -7.2 C (19.0 F) | 1990 | -3.9 C (25.0 F) | 52 |
| Wettest day (Rx1day) | 64.0 mm (2.5 in) | 2022 | 30.9 mm (1.2 in) | 52 |
| Wettest five days (Rx5day) | 127.9 mm (5.0 in) | 1983 | 46.5 mm (1.8 in) | 52 |
| Longest dry spell (CDD) | 180 days | 1984 | 76 days | 52 |
Hottest day (TXx)
| Year | Hottest day (TXx) |
|---|---|
| 1975 | 47.2 C (117.0 F) |
| 1976 | 47.8 C (118.0 F) |
| 1977 | 45.0 C (113.0 F) |
| 1978 | 46.7 C (116.1 F) |
| 1979 | 46.7 C (116.1 F) |
| 1980 | 47.2 C (117.0 F) |
| 1981 | 46.1 C (115.0 F) |
| 1982 | 45.0 C (113.0 F) |
| 1983 | 46.1 C (115.0 F) |
| 1984 | 46.7 C (116.1 F) |
| 1985 | 47.8 C (118.0 F) |
| 1986 | 46.1 C (115.0 F) |
| 1987 | 46.1 C (115.0 F) |
| 1988 | 47.2 C (117.0 F) |
| 1989 | 47.8 C (118.0 F) |
| 1990 | 47.8 C (118.0 F) |
| 1991 | 46.1 C (115.0 F) |
| 1992 | 46.1 C (115.0 F) |
| 1993 | 48.3 C (118.9 F) |
| 1994 | 50.6 C (123.1 F) |
| 1995 | 51.1 C (124.0 F) |
| 1996 | 47.2 C (117.0 F) |
| 1997 | 46.7 C (116.1 F) |
| 1998 | 50.6 C (123.1 F) |
| 1999 | 46.1 C (115.0 F) |
| 2000 | 47.2 C (117.0 F) |
| 2001 | 48.3 C (118.9 F) |
| 2002 | 46.1 C (115.0 F) |
| 2003 | 48.3 C (118.9 F) |
| 2004 | 46.1 C (115.0 F) |
| 2005 | 48.9 C (120.0 F) |
| 2006 | 48.3 C (118.9 F) |
| 2007 | 48.3 C (118.9 F) |
| 2008 | 47.2 C (117.0 F) |
| 2009 | 47.2 C (117.0 F) |
| 2010 | 47.2 C (117.0 F) |
| 2011 | 48.9 C (120.0 F) |
| 2012 | 47.2 C (117.0 F) |
| 2013 | 48.9 C (120.0 F) |
| 2014 | 46.7 C (116.1 F) |
| 2015 | 47.2 C (117.0 F) |
| 2016 | 50.0 C (122.0 F) |
| 2017 | 50.0 C (122.0 F) |
| 2018 | 47.8 C (118.0 F) |
| 2019 | 46.7 C (116.1 F) |
| 2020 | 49.4 C (120.9 F) |
| 2021 | 48.9 C (120.0 F) |
| 2022 | 46.7 C (116.1 F) |
| 2023 | 48.3 C (118.9 F) |
| 2024 | 50.6 C (123.1 F) |
| 2025 | 46.1 C (115.0 F) |
| 2026 | 47.2 C (117.0 F) |
Coldest night (TNn)
| Year | Coldest night (TNn) |
|---|---|
| 1975 | -2.8 C (27.0 F) |
| 1976 | -5.0 C (23.0 F) |
| 1977 | -3.3 C (26.1 F) |
| 1978 | -5.0 C (23.0 F) |
| 1979 | -3.9 C (25.0 F) |
| 1980 | 0.6 C (33.1 F) |
| 1981 | -1.1 C (30.0 F) |
| 1982 | -1.1 C (30.0 F) |
| 1983 | -2.8 C (27.0 F) |
| 1984 | -1.7 C (28.9 F) |
| 1985 | -2.8 C (27.0 F) |
| 1986 | -5.6 C (21.9 F) |
| 1987 | -5.0 C (23.0 F) |
| 1988 | -4.4 C (24.1 F) |
| 1989 | -4.4 C (24.1 F) |
| 1990 | -7.2 C (19.0 F) |
| 1991 | -3.9 C (25.0 F) |
| 1992 | -3.9 C (25.0 F) |
| 1993 | -3.9 C (25.0 F) |
| 1994 | -3.3 C (26.1 F) |
| 1995 | -3.9 C (25.0 F) |
| 1996 | -3.9 C (25.0 F) |
| 1997 | -2.2 C (28.0 F) |
| 1998 | -3.3 C (26.1 F) |
| 1999 | -2.2 C (28.0 F) |
| 2000 | -3.3 C (26.1 F) |
| 2001 | -5.6 C (21.9 F) |
| 2002 | -5.6 C (21.9 F) |
| 2003 | -3.9 C (25.0 F) |
| 2004 | -2.8 C (27.0 F) |
| 2005 | -4.4 C (24.1 F) |
| 2006 | -3.3 C (26.1 F) |
| 2007 | -7.2 C (19.0 F) |
| 2008 | -1.7 C (28.9 F) |
| 2009 | -0.6 C (30.9 F) |
| 2010 | -3.9 C (25.0 F) |
| 2011 | -6.1 C (21.0 F) |
| 2012 | -2.8 C (27.0 F) |
| 2013 | -6.1 C (21.0 F) |
| 2014 | -3.9 C (25.0 F) |
| 2015 | -6.7 C (19.9 F) |
| 2016 | -5.6 C (21.9 F) |
| 2017 | -4.4 C (24.1 F) |
| 2018 | -5.0 C (23.0 F) |
| 2019 | -7.2 C (19.0 F) |
| 2020 | -4.4 C (24.1 F) |
| 2021 | -2.2 C (28.0 F) |
| 2022 | -4.4 C (24.1 F) |
| 2023 | -7.2 C (19.0 F) |
| 2024 | -2.2 C (28.0 F) |
| 2025 | -3.9 C (25.0 F) |
| 2026 | -1.1 C (30.0 F) |
Wettest day (Rx1day)
| Year | Wettest day (Rx1day) |
|---|---|
| 1975 | 21.3 mm (0.8 in) |
| 1976 | 39.6 mm (1.6 in) |
| 1977 | 10.9 mm (0.4 in) |
| 1978 | 31.8 mm (1.3 in) |
| 1979 | 37.8 mm (1.5 in) |
| 1980 | 39.4 mm (1.6 in) |
| 1981 | 23.6 mm (0.9 in) |
| 1982 | 49.8 mm (2.0 in) |
| 1983 | 59.2 mm (2.3 in) |
| 1984 | 63.5 mm (2.5 in) |
| 1985 | 37.3 mm (1.5 in) |
| 1986 | 26.9 mm (1.1 in) |
| 1987 | 22.1 mm (0.9 in) |
| 1988 | 39.9 mm (1.6 in) |
| 1989 | 30.0 mm (1.2 in) |
| 1990 | 19.1 mm (0.8 in) |
| 1991 | 22.6 mm (0.9 in) |
| 1992 | 46.5 mm (1.8 in) |
| 1993 | 42.2 mm (1.7 in) |
| 1994 | 54.4 mm (2.1 in) |
| 1995 | 33.3 mm (1.3 in) |
| 1996 | 14.2 mm (0.6 in) |
| 1997 | 45.7 mm (1.8 in) |
| 1998 | 24.1 mm (0.9 in) |
| 1999 | 20.8 mm (0.8 in) |
| 2000 | 35.8 mm (1.4 in) |
| 2001 | 31.2 mm (1.2 in) |
| 2002 | 19.3 mm (0.8 in) |
| 2003 | 32.5 mm (1.3 in) |
| 2004 | 58.4 mm (2.3 in) |
| 2005 | 60.5 mm (2.4 in) |
| 2006 | 21.3 mm (0.8 in) |
| 2007 | 48.8 mm (1.9 in) |
| 2008 | 45.7 mm (1.8 in) |
| 2009 | 28.4 mm (1.1 in) |
| 2010 | 27.9 mm (1.1 in) |
| 2011 | 16.5 mm (0.6 in) |
| 2012 | 36.3 mm (1.4 in) |
| 2013 | 26.9 mm (1.1 in) |
| 2014 | 43.4 mm (1.7 in) |
| 2015 | 29.0 mm (1.1 in) |
| 2016 | 26.7 mm (1.1 in) |
| 2017 | 29.7 mm (1.2 in) |
| 2018 | 27.7 mm (1.1 in) |
| 2019 | 49.5 mm (1.9 in) |
| 2020 | 31.5 mm (1.2 in) |
| 2021 | 30.5 mm (1.2 in) |
| 2022 | 64.0 mm (2.5 in) |
| 2023 | 17.5 mm (0.7 in) |
| 2024 | 13.0 mm (0.5 in) |
| 2025 | 22.9 mm (0.9 in) |
| 2026 | 14.5 mm (0.6 in) |
Wettest five days (Rx5day)
| Year | Wettest five days (Rx5day) |
|---|---|
| 1975 | 25.8 mm (1.0 in) |
| 1976 | 53.1 mm (2.1 in) |
| 1977 | 12.4 mm (0.5 in) |
| 1978 | 63.6 mm (2.5 in) |
| 1979 | 46.0 mm (1.8 in) |
| 1980 | 46.8 mm (1.8 in) |
| 1981 | 42.2 mm (1.7 in) |
| 1982 | 71.1 mm (2.8 in) |
| 1983 | 127.9 mm (5.0 in) |
| 1984 | 70.9 mm (2.8 in) |
| 1985 | 25.9 mm (1.0 in) |
| 1986 | 32.7 mm (1.3 in) |
| 1987 | 35.8 mm (1.4 in) |
| 1988 | 79.8 mm (3.1 in) |
| 1989 | 46.5 mm (1.8 in) |
| 1990 | 25.4 mm (1.0 in) |
| 1991 | 58.9 mm (2.3 in) |
| 1992 | 47.0 mm (1.9 in) |
| 1993 | 62.8 mm (2.5 in) |
| 1994 | 54.9 mm (2.2 in) |
| 1995 | 36.1 mm (1.4 in) |
| 1996 | 18.0 mm (0.7 in) |
| 1997 | 53.3 mm (2.1 in) |
| 1998 | 46.8 mm (1.8 in) |
| 1999 | 46.2 mm (1.8 in) |
| 2000 | 43.5 mm (1.7 in) |
| 2001 | 31.2 mm (1.2 in) |
| 2002 | 20.3 mm (0.8 in) |
| 2003 | 42.4 mm (1.7 in) |
| 2004 | 86.1 mm (3.4 in) |
| 2005 | 63.3 mm (2.5 in) |
| 2006 | 22.6 mm (0.9 in) |
| 2007 | 48.8 mm (1.9 in) |
| 2008 | 46.5 mm (1.8 in) |
| 2009 | 28.4 mm (1.1 in) |
| 2010 | 60.7 mm (2.4 in) |
| 2011 | 30.2 mm (1.2 in) |
| 2012 | 69.1 mm (2.7 in) |
| 2013 | 37.3 mm (1.5 in) |
| 2014 | 74.6 mm (2.9 in) |
| 2015 | 35.6 mm (1.4 in) |
| 2016 | 46.8 mm (1.8 in) |
| 2017 | 30.5 mm (1.2 in) |
| 2018 | 38.7 mm (1.5 in) |
| 2019 | 74.1 mm (2.9 in) |
| 2020 | 60.8 mm (2.4 in) |
| 2021 | 48.4 mm (1.9 in) |
| 2022 | 64.8 mm (2.6 in) |
| 2023 | 29.9 mm (1.2 in) |
| 2024 | 22.3 mm (0.9 in) |
| 2025 | 58.2 mm (2.3 in) |
| 2026 | 20.9 mm (0.8 in) |
Longest dry spell (CDD)
| Year | Longest dry spell (CDD) |
|---|---|
| 1975 | 79 days |
| 1976 | 69 days |
| 1977 | 49 days |
| 1978 | 107 days |
| 1979 | 65 days |
| 1980 | 77 days |
| 1981 | 115 days |
| 1982 | 78 days |
| 1983 | 101 days |
| 1984 | 180 days |
| 1985 | 56 days |
| 1986 | 58 days |
| 1987 | 78 days |
| 1988 | 74 days |
| 1989 | 67 days |
| 1990 | 49 days |
| 1991 | 99 days |
| 1992 | 90 days |
| 1993 | 82 days |
| 1994 | 54 days |
| 1995 | 70 days |
| 1996 | 72 days |
| 1997 | 64 days |
| 1998 | 45 days |
| 1999 | 98 days |
| 2000 | 85 days |
| 2001 | 44 days |
| 2002 | 107 days |
| 2003 | 106 days |
| 2004 | 101 days |
| 2005 | 90 days |
| 2006 | 106 days |
| 2007 | 121 days |
| 2008 | 76 days |
| 2009 | 118 days |
| 2010 | 93 days |
| 2011 | 38 days |
| 2012 | 30 days |
| 2013 | 109 days |
| 2014 | 68 days |
| 2015 | 36 days |
| 2016 | 67 days |
| 2017 | 54 days |
| 2018 | 76 days |
| 2019 | 77 days |
| 2020 | 70 days |
| 2021 | 41 days |
| 2022 | 30 days |
| 2023 | 68 days |
| 2024 | 133 days |
| 2025 | 50 days |
| 2026 | 105 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
39 years with a frostAcross 39 years with a frost, the median last spring frost at Alamo Dam falls on 17 February and the median first autumn frost on 1 December, which leaves a median of 288 days between them.
Fitted over all years, the growing season changes by -3.6 days per decade at this station.
| Measure | Median, all years | Earliest period | Recent period (1987 to 2024) | Recent against earliest | Fitted trend |
|---|---|---|---|---|---|
| Last spring frost | 17 February | n/a | 19 February | n/a | +2.6 days per decade |
| First autumn frost | 1 December | n/a | 1 December | n/a | -1.0 days per decade |
| Growing days | 288 days | n/a | 288 days | n/a | -3.6 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
48 years, 1976 to 2025A day with at least 32.0 mm (1.3 in) of rain is expected about once in 2 years. A day with at least 76.1 mm (3.0 in) of rain is expected about once in 100 years.
| Expected about once in | A day with at least | Note |
|---|---|---|
| 2 years | 32.0 mm (1.3 in) | |
| 5 years | 44.8 mm (1.8 in) | |
| 10 years | 52.9 mm (2.1 in) | |
| 25 years | 62.6 mm (2.5 in) | |
| 50 years | 69.5 mm (2.7 in) | Longer than the 48 years of record |
| 100 years | 76.1 mm (3.0 in) | Longer than the 48 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, 48 years of values from 1976 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: 64.0 mm (2.5 in) in 2022; 63.5 mm (2.5 in) in 1984; 60.5 mm (2.4 in) in 2005.
Station Changes
1 suspectedOne change was suspected in the annual mean temperature of Alamo Dam, at 2014. Each is measured against neighbouring stations.
- Relative to 5 neighbouring stations, the station's annual mean temperature from 2014 ran 0.4 C (0.7 F) lower than in the years before (likely change).
| Year | Shift (C) | Shift (F) | Strength | Neighbours |
|---|---|---|---|---|
| 2014 | -0.4 | -0.7 | likely | 5 |
Possible change at the station (a move, a new instrument or a new site); the record is kept as measured. A "likely" change has a larger test statistic than a "possible" one. Neither says why the station differs from its neighbours. How changes are found, and the largest ones.
Climate Twins
2003 to 2025 against 1961 to 1990Over 2003 to 2025, Alamo Dam had a mean temperature of 21.9 C (71.3 F) and 206.4 mm (8.1 in) of rain a year. The 3 stations whose 1961 to 1990 climate was closest to that are Willow Beach (United States, 207 km away), Buckeye (United States, 132 km away) and Blythe (United States, 116 km away).
| Twin station | Country | Distance away | Mean temperature, 1961-1990 | Rain a year, 1961-1990 | Climate difference |
|---|---|---|---|---|---|
| Willow Beach | United States | 207 km (129 mi) | 22.3 C (72.1 F) | 129.3 mm (5.1 in) | 0.72 |
| Buckeye | United States | 132 km (82 mi) | 21.7 C (71.0 F) | 182.2 mm (7.2 in) | 0.74 |
| Blythe | United States | 116 km (72 mi) | 22.0 C (71.5 F) | 88.5 mm (3.5 in) | 0.88 |
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
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 2026-10-13 (13 October 2026). Records are computed by this site and are not official.
Data as of . Last revised (2026-10-13).