Half Moon Bay Weather Records (USC00043714)
Record envelope, standing records and threshold days for Half Moon Bay (USC00043714), California, United States, with 88 years of record.
Key Facts for Half Moon Bay
- Half Moon Bay (USC00043714) is a weather station in California, United States at 37.47 latitude and -122.44 longitude, 8 m (27 ft) above sea level.
- The station reports from 1939 to 2026, 88 years of record.
- 1,464 records set at Half Moon Bay still stand.
- Records are tracked for tmax, tmin, prcp, snow, snwd: an element needs 30 years of data to be eligible.
- Half Moon Bay set a daily record high minimum temperature of 15.6 C (60.1 F) on 10 October 2026 (provisional).
Provisional Records
Records set in the last 60 days are provisional until they clear the revision window.
About the Station
- Location: California, United States, 37.47 latitude, -122.44 longitude.
- Elevation: 8 m (27 ft).
- Period of record: 1939 to 2026, 88 years.
- Eligible elements: tmax, tmin, prcp, snow, snwd.
Daily Record Envelope and 2026
9 days at or beyond a record| Month | Highest record high | Lowest record low | 2026 highest maximum | 2026 lowest minimum |
|---|---|---|---|---|
| Jan | 24.4 C (75.9 F) | -2.8 C (27.0 F) | 21.7 C (71.1 F) | 2.8 C (37.0 F) |
| Feb | 26.1 C (79.0 F) | -5.6 C (21.9 F) | 26.1 C (79.0 F) | 1.7 C (35.1 F) |
| Mar | 28.3 C (82.9 F) | -2.2 C (28.0 F) | 23.9 C (75.0 F) | 3.9 C (39.0 F) |
| Apr | 28.9 C (84.0 F) | -0.6 C (30.9 F) | 25.0 C (77.0 F) | 3.9 C (39.0 F) |
| May | 27.8 C (82.0 F) | 0.6 C (33.1 F) | 25.0 C (77.0 F) | 4.4 C (39.9 F) |
| Jun | 31.7 C (89.1 F) | 2.2 C (36.0 F) | 19.4 C (66.9 F) | 6.7 C (44.1 F) |
| Jul | 27.2 C (81.0 F) | 4.4 C (39.9 F) | 25.0 C (77.0 F) | 8.9 C (48.0 F) |
| Aug | 31.1 C (88.0 F) | 5.0 C (41.0 F) | 20.0 C (68.0 F) | 9.4 C (48.9 F) |
| Sep | 33.3 C (91.9 F) | 1.7 C (35.1 F) | 28.3 C (82.9 F) | 8.3 C (46.9 F) |
| Oct | 34.4 C (93.9 F) | 0.6 C (33.1 F) | 21.7 C (71.1 F) | 5.6 C (42.1 F) |
| Nov | 30.6 C (87.1 F) | -1.1 C (30.0 F) | n/a | n/a |
| Dec | 26.1 C (79.0 F) | -7.2 C (19.0 F) | n/a | n/a |
Which Years Hold Standing Records
1,464 standing records| Year set | Standing records |
|---|---|
| 1939 | 16 |
| 1940 | 10 |
| 1941 | 20 |
| 1942 | 14 |
| 1943 | 19 |
| 1944 | 10 |
| 1945 | 17 |
| 1946 | 12 |
| 1947 | 16 |
| 1948 | 13 |
| 1949 | 43 |
| 1950 | 19 |
| 1951 | 45 |
| 1952 | 33 |
| 1953 | 17 |
| 1954 | 25 |
| 1955 | 42 |
| 1956 | 13 |
| 1957 | 18 |
| 1958 | 25 |
| 1959 | 20 |
| 1960 | 11 |
| 1961 | 17 |
| 1962 | 21 |
| 1963 | 7 |
| 1964 | 17 |
| 1965 | 15 |
| 1966 | 18 |
| 1967 | 13 |
| 1968 | 22 |
| 1969 | 38 |
| 1970 | 16 |
| 1971 | 12 |
| 1972 | 16 |
| 1973 | 4 |
| 1974 | 6 |
| 1975 | 23 |
| 1976 | 12 |
| 1977 | 7 |
| 1978 | 12 |
| 1979 | 6 |
| 1980 | 5 |
| 1981 | 6 |
| 1982 | 17 |
| 1983 | 14 |
| 1984 | 7 |
| 1985 | 4 |
| 1986 | 3 |
| 1987 | 8 |
| 1988 | 10 |
| 1989 | 21 |
| 1990 | 15 |
| 1991 | 27 |
| 1992 | 22 |
| 1993 | 10 |
| 1994 | 5 |
| 1995 | 12 |
| 1996 | 10 |
| 1997 | 17 |
| 1998 | 7 |
| 1999 | 17 |
| 2000 | 8 |
| 2001 | 11 |
| 2002 | 10 |
| 2003 | 16 |
| 2004 | 32 |
| 2005 | 18 |
| 2006 | 17 |
| 2007 | 26 |
| 2008 | 39 |
| 2009 | 34 |
| 2010 | 11 |
| 2011 | 10 |
| 2012 | 12 |
| 2013 | 16 |
| 2014 | 22 |
| 2015 | 32 |
| 2016 | 10 |
| 2017 | 20 |
| 2018 | 15 |
| 2019 | 22 |
| 2020 | 11 |
| 2021 | 10 |
| 2022 | 18 |
| 2023 | 10 |
| 2024 | 10 |
| 2025 | 21 |
| 2026 | 26 |
All-Time Record Progression
9 new records| Date | Kind | Detail |
|---|---|---|
| 1972-12-09 | Record low maximum temperature | Record low maximum temperature 2.8 C (37.0 F) |
| 1982-01-04 | Record daily precipitation | Record daily precipitation 135.4 mm (5.3 in) |
| 1983-09-19 | Record high minimum temperature | Record high minimum temperature 21.1 C (70.0 F) |
| 1990-12-20 | Record low minimum temperature | Record low minimum temperature -3.9 C (25.0 F) |
| 1990-12-21 | Record low minimum temperature | Record low minimum temperature -4.4 C (24.1 F) |
| 1990-12-23 | Record low minimum temperature | Record low minimum temperature -7.2 C (19.0 F) |
| 2001-09-30 | Record high maximum temperature | Record high maximum temperature 33.3 C (91.9 F) |
| 2002-12-16 | Record daily precipitation | Record daily precipitation 139.7 mm (5.5 in) |
| 2003-10-26 | Record high maximum temperature | Record high maximum temperature 34.4 C (93.9 F) |
Wettest Day of Each Month
Dec: 139.7 mm (5.5 in)| Month | Record daily precipitation (mm) | Date |
|---|---|---|
| Jan | 135.4 mm (5.3 in) | 4 January 1982 |
| Feb | 74.2 mm (2.9 in) | 3 February 1998 |
| Mar | 97.8 mm (3.9 in) | 30 March 1940 |
| Apr | 59.9 mm (2.4 in) | 4 April 1941 |
| May | 32.5 mm (1.3 in) | 27 May 1990 |
| Jun | 28.4 mm (1.1 in) | 2 June 1967 |
| Jul | 15.2 mm (0.6 in) | 8 July 1974 |
| Aug | 18.3 mm (0.7 in) | 20 August 1997 |
| Sep | 65.0 mm (2.6 in) | 19 September 1959 |
| Oct | 124.5 mm (4.9 in) | 13 October 1962 |
| Nov | 71.9 mm (2.8 in) | 18 November 1982 |
| Dec | 139.7 mm (5.5 in) | 16 December 2002 |
Period of Record Coverage
1939 to 2026| Year | Days with data | Share of year | Complete |
|---|---|---|---|
| 1939 | 182 | 50% | No |
| 1940 | 366 | 100% | Yes |
| 1941 | 349 | 96% | Yes |
| 1942 | 362 | 99% | Yes |
| 1943 | 362 | 99% | Yes |
| 1944 | 365 | 100% | Yes |
| 1945 | 359 | 98% | Yes |
| 1946 | 364 | 100% | Yes |
| 1947 | 359 | 98% | Yes |
| 1948 | 366 | 100% | Yes |
| 1949 | 285 | 78% | No |
| 1950 | 318 | 87% | No |
| 1951 | 360 | 99% | Yes |
| 1952 | 366 | 100% | Yes |
| 1953 | 313 | 86% | No |
| 1954 | 365 | 100% | Yes |
| 1955 | 357 | 98% | Yes |
| 1956 | 358 | 98% | Yes |
| 1957 | 354 | 97% | Yes |
| 1958 | 350 | 96% | Yes |
| 1959 | 350 | 96% | Yes |
| 1960 | 366 | 100% | Yes |
| 1961 | 362 | 99% | Yes |
| 1962 | 360 | 99% | Yes |
| 1963 | 350 | 96% | Yes |
| 1964 | 359 | 98% | Yes |
| 1965 | 363 | 99% | Yes |
| 1966 | 358 | 98% | Yes |
| 1967 | 357 | 98% | Yes |
| 1968 | 359 | 98% | Yes |
| 1969 | 362 | 99% | Yes |
| 1970 | 362 | 99% | Yes |
| 1971 | 365 | 100% | Yes |
| 1972 | 363 | 99% | Yes |
| 1973 | 334 | 92% | Yes |
| 1974 | 365 | 100% | Yes |
| 1975 | 355 | 97% | Yes |
| 1976 | 360 | 98% | Yes |
| 1977 | 359 | 98% | Yes |
| 1978 | 358 | 98% | Yes |
| 1979 | 362 | 99% | Yes |
| 1980 | 361 | 99% | Yes |
| 1981 | 363 | 99% | Yes |
| 1982 | 362 | 99% | Yes |
| 1983 | 346 | 95% | Yes |
| 1984 | 358 | 98% | Yes |
| 1985 | 327 | 90% | No |
| 1986 | 363 | 99% | Yes |
| 1987 | 302 | 83% | No |
| 1988 | 298 | 81% | No |
| 1989 | 345 | 95% | Yes |
| 1990 | 355 | 97% | Yes |
| 1991 | 360 | 99% | Yes |
| 1992 | 359 | 98% | Yes |
| 1993 | 339 | 93% | Yes |
| 1994 | 323 | 88% | No |
| 1995 | 351 | 96% | Yes |
| 1996 | 347 | 95% | Yes |
| 1997 | 346 | 95% | Yes |
| 1998 | 350 | 96% | Yes |
| 1999 | 351 | 96% | Yes |
| 2000 | 361 | 99% | Yes |
| 2001 | 263 | 72% | No |
| 2002 | 132 | 36% | No |
| 2003 | 155 | 42% | No |
| 2004 | 359 | 98% | Yes |
| 2005 | 363 | 99% | Yes |
| 2006 | 361 | 99% | Yes |
| 2007 | 361 | 99% | Yes |
| 2008 | 364 | 99% | Yes |
| 2009 | 358 | 98% | Yes |
| 2010 | 364 | 100% | Yes |
| 2011 | 362 | 99% | Yes |
| 2012 | 363 | 99% | Yes |
| 2013 | 359 | 98% | Yes |
| 2014 | 358 | 98% | Yes |
| 2015 | 361 | 99% | Yes |
| 2016 | 359 | 98% | Yes |
| 2017 | 362 | 99% | Yes |
| 2018 | 365 | 100% | Yes |
| 2019 | 360 | 99% | Yes |
| 2020 | 365 | 100% | Yes |
| 2021 | 361 | 99% | Yes |
| 2022 | 363 | 99% | Yes |
| 2023 | 361 | 99% | Yes |
| 2024 | 365 | 100% | Yes |
| 2025 | 365 | 100% | Yes |
| 2026 | 286 | 78% | No |
Latest Records
20| Date | Station | Record | Value | Beat old record by | Old record stood | Significance |
|---|---|---|---|---|---|---|
| 10 October 2026 | Half Moon Bay, US | daily high min (Provisional) | 15.6 C (60.1 F) | 1.2 C (2.2 F) | 68 years | 32 of 100 (Routine) |
| 9 October 2026 | Half Moon Bay, US | daily high min (Provisional) | 15.6 C (60.1 F) | 1.7 C (3.1 F) | 25 years | 21 of 100 (Routine) |
| 6 October 2026 | Half Moon Bay, US | daily high min (Provisional) | 15.6 C (60.1 F) | 1.2 C (2.2 F) | 43 years | 24 of 100 (Routine) |
| 17 September 2026 | Half Moon Bay, US | daily high min (Provisional) | 16.1 C (61.0 F) | 0.5 C (0.9 F) | 59 years | 26 of 100 (Routine) |
| 9 September 2026 | Half Moon Bay, US | daily high max (Provisional) | 28.3 C (82.9 F) | 2.2 C (4.0 F) | 47 years | 29 of 100 (Routine) |
| 27 August 2026 | Half Moon Bay, US | daily high min (Provisional) | 14.4 C (57.9 F) | 0.5 C (0.9 F) | 79 years | 33 of 100 (Routine) |
| 14 August 2026 | Half Moon Bay, US | daily high min (Tie) | 15.6 C (60.1 F) | tie | 64 years | 6 of 100 (Routine) |
| 5 August 2026 | Half Moon Bay, US | daily high min (Tie) | 15.0 C (59.0 F) | tie | 12 years | 2 of 100 (Routine) |
| 27 July 2026 | Half Moon Bay, US | daily high min | 15.0 C (59.0 F) | 0.6 C (1.1 F) | 12 years | 14 of 100 (Routine) |
| 26 July 2026 | Half Moon Bay, US | daily high min | 15.6 C (60.1 F) | 1.2 C (2.2 F) | 11 years | 17 of 100 (Routine) |
| 22 July 2026 | Half Moon Bay, US | daily high max | 25.0 C (77.0 F) | 2.2 C (4.0 F) | 19 years | 25 of 100 (Routine) |
| 22 July 2026 | Half Moon Bay, US | daily high min | 16.1 C (61.0 F) | 1.1 C (2.0 F) | 19 years | 18 of 100 (Routine) |
| 21 July 2026 | Half Moon Bay, US | daily high max | 23.3 C (73.9 F) | 1.1 C (2.0 F) | 19 years | 19 of 100 (Routine) |
| 6 July 2026 | Half Moon Bay, US | daily rain | 3.8 mm (0.15 in) | 2.5 mm (0.10 in) | 4 years | 20 of 100 (Routine) |
| 20 June 2026 | Half Moon Bay, US | monthly high min (Tie) | 15.6 C (60.1 F) | tie | 33 years | 7 of 100 (Routine) |
| 19 June 2026 | Half Moon Bay, US | daily high min | 15.0 C (59.0 F) | 1.7 C (3.1 F) | 21 years | 21 of 100 (Routine) |
| 18 June 2026 | Half Moon Bay, US | daily high min (Tie) | 13.9 C (57.0 F) | tie | 64 years | 6 of 100 (Routine) |
| 16 June 2026 | Half Moon Bay, US | daily high min (Tie) | 13.9 C (57.0 F) | tie | 16 years | 3 of 100 (Routine) |
| 15 June 2026 | Half Moon Bay, US | daily high min | 13.9 C (57.0 F) | 1.1 C (2.0 F) | 77 years | 36 of 100 (Notable) |
| 9 June 2026 | Half Moon Bay, US | daily high min (Tie) | 13.3 C (55.9 F) | tie | 68 years | 7 of 100 (Routine) |
Climate Trend
74 complete years, 1940 to 2025| Year | Annual mean temperature | Difference from the station mean |
|---|---|---|
| 1940 | 13.5 C | +0.88 C |
| 1942 | 12.5 C | -0.18 C |
| 1943 | 12.8 C | +0.16 C |
| 1944 | 12.1 C | -0.52 C |
| 1945 | 12.1 C | -0.51 C |
| 1946 | 11.8 C | -0.83 C |
| 1947 | 12.6 C | -0.01 C |
| 1948 | 12.0 C | -0.62 C |
| 1951 | 11.8 C | -0.84 C |
| 1952 | 12.1 C | -0.49 C |
| 1954 | 12.0 C | -0.60 C |
| 1955 | 11.2 C | -1.42 C |
| 1956 | 12.5 C | -0.10 C |
| 1957 | 13.1 C | +0.48 C |
| 1958 | 13.8 C | +1.12 C |
| 1959 | 13.5 C | +0.88 C |
| 1960 | 12.8 C | +0.17 C |
| 1961 | 13.1 C | +0.51 C |
| 1962 | 12.1 C | -0.51 C |
| 1963 | 12.6 C | -0.01 C |
| 1964 | 12.3 C | -0.38 C |
| 1965 | 12.5 C | -0.14 C |
| 1966 | 12.3 C | -0.36 C |
| 1967 | 12.8 C | +0.16 C |
| 1968 | 12.8 C | +0.12 C |
| 1969 | 11.8 C | -0.84 C |
| 1970 | 12.4 C | -0.24 C |
| 1971 | 11.5 C | -1.17 C |
| 1972 | 12.4 C | -0.24 C |
| 1974 | 12.5 C | -0.16 C |
| 1975 | 11.6 C | -1.03 C |
| 1976 | 12.8 C | +0.12 C |
| 1977 | 12.6 C | -0.06 C |
| 1978 | 12.9 C | +0.25 C |
| 1979 | 12.8 C | +0.20 C |
| 1980 | 13.0 C | +0.37 C |
| 1981 | 13.0 C | +0.38 C |
| 1982 | 12.8 C | +0.17 C |
| 1983 | 13.8 C | +1.21 C |
| 1984 | 12.7 C | +0.03 C |
| 1986 | 13.3 C | +0.62 C |
| 1989 | 12.7 C | +0.02 C |
| 1990 | 12.2 C | -0.40 C |
| 1991 | 11.5 C | -1.11 C |
| 1992 | 13.6 C | +0.94 C |
| 1993 | 12.3 C | -0.33 C |
| 1995 | 13.2 C | +0.61 C |
| 1996 | 12.8 C | +0.17 C |
| 1997 | 13.6 C | +0.96 C |
| 1998 | 12.6 C | -0.03 C |
| 1999 | 12.0 C | -0.67 C |
| 2000 | 13.0 C | +0.33 C |
| 2004 | 13.0 C | +0.37 C |
| 2005 | 13.0 C | +0.39 C |
| 2006 | 12.5 C | -0.10 C |
| 2007 | 12.0 C | -0.59 C |
| 2008 | 11.9 C | -0.77 C |
| 2009 | 12.6 C | -0.02 C |
| 2010 | 12.6 C | -0.07 C |
| 2011 | 12.4 C | -0.25 C |
| 2012 | 12.4 C | -0.21 C |
| 2013 | 12.6 C | -0.07 C |
| 2014 | 14.1 C | +1.45 C |
| 2015 | 13.9 C | +1.24 C |
| 2016 | 13.3 C | +0.67 C |
| 2017 | 13.2 C | +0.57 C |
| 2018 | 12.7 C | +0.08 C |
| 2019 | 13.0 C | +0.40 C |
| 2020 | 12.8 C | +0.19 C |
| 2021 | 12.5 C | -0.13 C |
| 2022 | 12.1 C | -0.53 C |
| 2023 | 12.4 C | -0.22 C |
| 2024 | 12.5 C | -0.14 C |
| 2025 | 13.2 C | +0.60 C |
The fitted trend in annual mean temperature here over 1940 to 2025 is 0.1 C (0.0 to 0.1) per decade. The interval includes zero, so the trend is not clearly different from zero. In Fahrenheit: 0.1 F (0.0 to 0.2) per decade. The slope is a straight line fitted to 74 complete years; the brackets give its 95 percent interval.
| Measure | Per decade (C) | Per decade (F) | Period | Complete years | Reading |
|---|---|---|---|---|---|
| Annual mean temperature | 0.1 C (0.0 to 0.1) per decade | 0.1 F (0.0 to 0.2) per decade | 1940 to 2025 | 74 | Not clearly different from zero |
| Mean daily maximum | 0.07 C (0.01 to 0.13) per decade | 0.13 F (0.02 to 0.24) per decade | 1940 to 2025 | 74 | Rise |
| Mean daily minimum | 0.04 C (-0.03 to 0.10) per decade | 0.1 F (-0.1 to 0.2) per decade | 1940 to 2025 | 74 | 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
1939 to 2026| Measure | Record | Year of the record | Median year | Years with a value |
|---|---|---|---|---|
| Hottest day (TXx) | 34.4 C (93.9 F) | 2003 | 29.2 C (84.5 F) | 88 |
| Coldest night (TNn) | -7.2 C (19.0 F) | 1990 | -0.6 C (30.9 F) | 88 |
| Wettest day (Rx1day) | 139.7 mm (5.5 in) | 2002 | 50.8 mm (2.0 in) | 88 |
| Wettest five days (Rx5day) | 272.6 mm (10.7 in) | 1962 | 98.7 mm (3.9 in) | 88 |
| Longest dry spell (CDD) | 172 days | 1978 | 59 days | 88 |
Hottest day (TXx)
| Year | Hottest day (TXx) |
|---|---|
| 1939 | 32.2 C (90.0 F) |
| 1940 | 26.7 C (80.1 F) |
| 1941 | 30.6 C (87.1 F) |
| 1942 | 26.1 C (79.0 F) |
| 1943 | 28.3 C (82.9 F) |
| 1944 | 32.2 C (90.0 F) |
| 1945 | 28.3 C (82.9 F) |
| 1946 | 31.7 C (89.1 F) |
| 1947 | 31.1 C (88.0 F) |
| 1948 | 29.4 C (84.9 F) |
| 1949 | 27.8 C (82.0 F) |
| 1950 | 28.9 C (84.0 F) |
| 1951 | 28.9 C (84.0 F) |
| 1952 | 28.9 C (84.0 F) |
| 1953 | 30.6 C (87.1 F) |
| 1954 | 32.8 C (91.0 F) |
| 1955 | 30.0 C (86.0 F) |
| 1956 | 32.2 C (90.0 F) |
| 1957 | 28.3 C (82.9 F) |
| 1958 | 32.8 C (91.0 F) |
| 1959 | 31.1 C (88.0 F) |
| 1960 | 28.3 C (82.9 F) |
| 1961 | 32.2 C (90.0 F) |
| 1962 | 27.2 C (81.0 F) |
| 1963 | 23.9 C (75.0 F) |
| 1964 | 30.0 C (86.0 F) |
| 1965 | 32.8 C (91.0 F) |
| 1966 | 31.7 C (89.1 F) |
| 1967 | 30.6 C (87.1 F) |
| 1968 | 31.1 C (88.0 F) |
| 1969 | 26.7 C (80.1 F) |
| 1970 | 32.2 C (90.0 F) |
| 1971 | 25.6 C (78.1 F) |
| 1972 | 30.6 C (87.1 F) |
| 1973 | 27.8 C (82.0 F) |
| 1974 | 29.4 C (84.9 F) |
| 1975 | 26.1 C (79.0 F) |
| 1976 | 30.6 C (87.1 F) |
| 1977 | 24.4 C (75.9 F) |
| 1978 | 32.8 C (91.0 F) |
| 1979 | 32.2 C (90.0 F) |
| 1980 | 25.0 C (77.0 F) |
| 1981 | 26.1 C (79.0 F) |
| 1982 | 28.3 C (82.9 F) |
| 1983 | 31.1 C (88.0 F) |
| 1984 | 29.4 C (84.9 F) |
| 1985 | 26.7 C (80.1 F) |
| 1986 | 26.1 C (79.0 F) |
| 1987 | 27.8 C (82.0 F) |
| 1988 | 27.8 C (82.0 F) |
| 1989 | 27.8 C (82.0 F) |
| 1990 | 28.3 C (82.9 F) |
| 1991 | 32.8 C (91.0 F) |
| 1992 | 31.7 C (89.1 F) |
| 1993 | 31.7 C (89.1 F) |
| 1994 | 32.2 C (90.0 F) |
| 1995 | 31.1 C (88.0 F) |
| 1996 | 27.2 C (81.0 F) |
| 1997 | 32.2 C (90.0 F) |
| 1998 | 28.3 C (82.9 F) |
| 1999 | 28.9 C (84.0 F) |
| 2000 | 28.9 C (84.0 F) |
| 2001 | 33.3 C (91.9 F) |
| 2002 | 23.9 C (75.0 F) |
| 2003 | 34.4 C (93.9 F) |
| 2004 | 31.1 C (88.0 F) |
| 2005 | 27.2 C (81.0 F) |
| 2006 | 29.4 C (84.9 F) |
| 2007 | 29.4 C (84.9 F) |
| 2008 | 30.6 C (87.1 F) |
| 2009 | 28.9 C (84.0 F) |
| 2010 | 30.0 C (86.0 F) |
| 2011 | 28.9 C (84.0 F) |
| 2012 | 27.8 C (82.0 F) |
| 2013 | 27.8 C (82.0 F) |
| 2014 | 31.7 C (89.1 F) |
| 2015 | 25.6 C (78.1 F) |
| 2016 | 28.9 C (84.0 F) |
| 2017 | 33.3 C (91.9 F) |
| 2018 | 26.7 C (80.1 F) |
| 2019 | 33.3 C (91.9 F) |
| 2020 | 33.3 C (91.9 F) |
| 2021 | 25.6 C (78.1 F) |
| 2022 | 27.2 C (81.0 F) |
| 2023 | 32.2 C (90.0 F) |
| 2024 | 26.7 C (80.1 F) |
| 2025 | 27.2 C (81.0 F) |
| 2026 | 28.3 C (82.9 F) |
Coldest night (TNn)
| Year | Coldest night (TNn) |
|---|---|
| 1939 | 2.8 C (37.0 F) |
| 1940 | 0.0 C (32.0 F) |
| 1941 | 1.1 C (34.0 F) |
| 1942 | 0.6 C (33.1 F) |
| 1943 | -1.1 C (30.0 F) |
| 1944 | 0.0 C (32.0 F) |
| 1945 | 0.0 C (32.0 F) |
| 1946 | -0.6 C (30.9 F) |
| 1947 | -1.1 C (30.0 F) |
| 1948 | -1.7 C (28.9 F) |
| 1949 | -2.8 C (27.0 F) |
| 1950 | 1.1 C (34.0 F) |
| 1951 | -0.6 C (30.9 F) |
| 1952 | 0.0 C (32.0 F) |
| 1953 | 1.1 C (34.0 F) |
| 1954 | 0.6 C (33.1 F) |
| 1955 | -1.1 C (30.0 F) |
| 1956 | 0.0 C (32.0 F) |
| 1957 | -0.6 C (30.9 F) |
| 1958 | 0.0 C (32.0 F) |
| 1959 | 0.0 C (32.0 F) |
| 1960 | 0.0 C (32.0 F) |
| 1961 | 1.1 C (34.0 F) |
| 1962 | -1.1 C (30.0 F) |
| 1963 | 0.0 C (32.0 F) |
| 1964 | 0.6 C (33.1 F) |
| 1965 | 0.0 C (32.0 F) |
| 1966 | 0.0 C (32.0 F) |
| 1967 | 1.7 C (35.1 F) |
| 1968 | -1.1 C (30.0 F) |
| 1969 | -1.7 C (28.9 F) |
| 1970 | 1.7 C (35.1 F) |
| 1971 | 0.6 C (33.1 F) |
| 1972 | -2.8 C (27.0 F) |
| 1973 | 0.6 C (33.1 F) |
| 1974 | 0.6 C (33.1 F) |
| 1975 | -1.1 C (30.0 F) |
| 1976 | -0.6 C (30.9 F) |
| 1977 | 1.7 C (35.1 F) |
| 1978 | -1.7 C (28.9 F) |
| 1979 | -1.1 C (30.0 F) |
| 1980 | 0.0 C (32.0 F) |
| 1981 | 2.2 C (36.0 F) |
| 1982 | 1.1 C (34.0 F) |
| 1983 | -2.2 C (28.0 F) |
| 1984 | -1.1 C (30.0 F) |
| 1985 | 0.6 C (33.1 F) |
| 1986 | 2.2 C (36.0 F) |
| 1987 | 0.6 C (33.1 F) |
| 1988 | -1.7 C (28.9 F) |
| 1989 | -2.2 C (28.0 F) |
| 1990 | -7.2 C (19.0 F) |
| 1991 | -1.1 C (30.0 F) |
| 1992 | 0.6 C (33.1 F) |
| 1993 | 0.6 C (33.1 F) |
| 1994 | 0.0 C (32.0 F) |
| 1995 | 1.7 C (35.1 F) |
| 1996 | 0.6 C (33.1 F) |
| 1997 | 0.6 C (33.1 F) |
| 1998 | -2.2 C (28.0 F) |
| 1999 | 1.1 C (34.0 F) |
| 2000 | 0.0 C (32.0 F) |
| 2001 | -1.1 C (30.0 F) |
| 2002 | -1.1 C (30.0 F) |
| 2003 | -5.6 C (21.9 F) |
| 2004 | -0.6 C (30.9 F) |
| 2005 | -0.6 C (30.9 F) |
| 2006 | -2.2 C (28.0 F) |
| 2007 | -2.8 C (27.0 F) |
| 2008 | -0.6 C (30.9 F) |
| 2009 | -2.2 C (28.0 F) |
| 2010 | -0.6 C (30.9 F) |
| 2011 | -0.6 C (30.9 F) |
| 2012 | -2.2 C (28.0 F) |
| 2013 | -2.8 C (27.0 F) |
| 2014 | 1.1 C (34.0 F) |
| 2015 | -1.1 C (30.0 F) |
| 2016 | -0.6 C (30.9 F) |
| 2017 | -1.1 C (30.0 F) |
| 2018 | -2.2 C (28.0 F) |
| 2019 | -1.1 C (30.0 F) |
| 2020 | -1.1 C (30.0 F) |
| 2021 | -1.1 C (30.0 F) |
| 2022 | -1.7 C (28.9 F) |
| 2023 | -1.1 C (30.0 F) |
| 2024 | 0.6 C (33.1 F) |
| 2025 | -0.6 C (30.9 F) |
| 2026 | 1.7 C (35.1 F) |
Wettest day (Rx1day)
| Year | Wettest day (Rx1day) |
|---|---|
| 1939 | 11.7 mm (0.5 in) |
| 1940 | 97.8 mm (3.9 in) |
| 1941 | 59.9 mm (2.4 in) |
| 1942 | 60.5 mm (2.4 in) |
| 1943 | 89.2 mm (3.5 in) |
| 1944 | 44.2 mm (1.7 in) |
| 1945 | 60.5 mm (2.4 in) |
| 1946 | 65.0 mm (2.6 in) |
| 1947 | 40.6 mm (1.6 in) |
| 1948 | 49.3 mm (1.9 in) |
| 1949 | 28.4 mm (1.1 in) |
| 1950 | 40.6 mm (1.6 in) |
| 1951 | 50.5 mm (2.0 in) |
| 1952 | 57.7 mm (2.3 in) |
| 1953 | 58.7 mm (2.3 in) |
| 1954 | 48.0 mm (1.9 in) |
| 1955 | 71.1 mm (2.8 in) |
| 1956 | 33.0 mm (1.3 in) |
| 1957 | 35.6 mm (1.4 in) |
| 1958 | 55.9 mm (2.2 in) |
| 1959 | 65.0 mm (2.6 in) |
| 1960 | 23.6 mm (0.9 in) |
| 1961 | 46.5 mm (1.8 in) |
| 1962 | 124.5 mm (4.9 in) |
| 1963 | 55.4 mm (2.2 in) |
| 1964 | 73.9 mm (2.9 in) |
| 1965 | 45.7 mm (1.8 in) |
| 1966 | 44.7 mm (1.8 in) |
| 1967 | 100.3 mm (3.9 in) |
| 1968 | 53.3 mm (2.1 in) |
| 1969 | 33.5 mm (1.3 in) |
| 1970 | 67.1 mm (2.6 in) |
| 1971 | 36.3 mm (1.4 in) |
| 1972 | 48.8 mm (1.9 in) |
| 1973 | 61.0 mm (2.4 in) |
| 1974 | 50.3 mm (2.0 in) |
| 1975 | 34.3 mm (1.4 in) |
| 1976 | 61.2 mm (2.4 in) |
| 1977 | 41.4 mm (1.6 in) |
| 1978 | 78.2 mm (3.1 in) |
| 1979 | 55.9 mm (2.2 in) |
| 1980 | 59.7 mm (2.4 in) |
| 1981 | 77.0 mm (3.0 in) |
| 1982 | 135.4 mm (5.3 in) |
| 1983 | 67.6 mm (2.7 in) |
| 1984 | 57.4 mm (2.3 in) |
| 1985 | 67.3 mm (2.6 in) |
| 1986 | 51.6 mm (2.0 in) |
| 1987 | 53.3 mm (2.1 in) |
| 1988 | 39.6 mm (1.6 in) |
| 1989 | 47.0 mm (1.9 in) |
| 1990 | 40.1 mm (1.6 in) |
| 1991 | 48.5 mm (1.9 in) |
| 1992 | 46.7 mm (1.8 in) |
| 1993 | 59.4 mm (2.3 in) |
| 1994 | 50.8 mm (2.0 in) |
| 1995 | 64.0 mm (2.5 in) |
| 1996 | 49.0 mm (1.9 in) |
| 1997 | 58.4 mm (2.3 in) |
| 1998 | 74.2 mm (2.9 in) |
| 1999 | 46.2 mm (1.8 in) |
| 2000 | 63.0 mm (2.5 in) |
| 2001 | 27.9 mm (1.1 in) |
| 2002 | 139.7 mm (5.5 in) |
| 2003 | 53.8 mm (2.1 in) |
| 2004 | 73.7 mm (2.9 in) |
| 2005 | 61.5 mm (2.4 in) |
| 2006 | 41.1 mm (1.6 in) |
| 2007 | 32.5 mm (1.3 in) |
| 2008 | 59.2 mm (2.3 in) |
| 2009 | 72.6 mm (2.9 in) |
| 2010 | 44.2 mm (1.7 in) |
| 2011 | 33.0 mm (1.3 in) |
| 2012 | 42.9 mm (1.7 in) |
| 2013 | 30.2 mm (1.2 in) |
| 2014 | 53.6 mm (2.1 in) |
| 2015 | 42.7 mm (1.7 in) |
| 2016 | 41.9 mm (1.6 in) |
| 2017 | 50.5 mm (2.0 in) |
| 2018 | 50.8 mm (2.0 in) |
| 2019 | 27.9 mm (1.1 in) |
| 2020 | 36.8 mm (1.4 in) |
| 2021 | 136.7 mm (5.4 in) |
| 2022 | 78.5 mm (3.1 in) |
| 2023 | 49.0 mm (1.9 in) |
| 2024 | 48.8 mm (1.9 in) |
| 2025 | 42.7 mm (1.7 in) |
| 2026 | 39.1 mm (1.5 in) |
Wettest five days (Rx5day)
| Year | Wettest five days (Rx5day) |
|---|---|
| 1939 | 12.7 mm (0.5 in) |
| 1940 | 146.6 mm (5.8 in) |
| 1941 | 112.1 mm (4.4 in) |
| 1942 | 125.2 mm (4.9 in) |
| 1943 | 165.6 mm (6.5 in) |
| 1944 | 72.9 mm (2.9 in) |
| 1945 | 96.6 mm (3.8 in) |
| 1946 | 81.2 mm (3.2 in) |
| 1947 | 48.0 mm (1.9 in) |
| 1948 | 66.9 mm (2.6 in) |
| 1949 | 52.1 mm (2.1 in) |
| 1950 | 110.2 mm (4.3 in) |
| 1951 | 108.2 mm (4.3 in) |
| 1952 | 164.4 mm (6.5 in) |
| 1953 | 71.4 mm (2.8 in) |
| 1954 | 76.9 mm (3.0 in) |
| 1955 | 190.8 mm (7.5 in) |
| 1956 | 67.0 mm (2.6 in) |
| 1957 | 67.7 mm (2.7 in) |
| 1958 | 131.1 mm (5.2 in) |
| 1959 | 92.9 mm (3.7 in) |
| 1960 | 73.0 mm (2.9 in) |
| 1961 | 90.0 mm (3.5 in) |
| 1962 | 272.6 mm (10.7 in) |
| 1963 | 126.5 mm (5.0 in) |
| 1964 | 111.0 mm (4.4 in) |
| 1965 | 93.0 mm (3.7 in) |
| 1966 | 93.0 mm (3.7 in) |
| 1967 | 170.1 mm (6.7 in) |
| 1968 | 92.7 mm (3.6 in) |
| 1969 | 87.6 mm (3.4 in) |
| 1970 | 140.0 mm (5.5 in) |
| 1971 | 52.3 mm (2.1 in) |
| 1972 | 126.3 mm (5.0 in) |
| 1973 | 131.4 mm (5.2 in) |
| 1974 | 91.5 mm (3.6 in) |
| 1975 | 79.6 mm (3.1 in) |
| 1976 | 61.2 mm (2.4 in) |
| 1977 | 114.5 mm (4.5 in) |
| 1978 | 141.7 mm (5.6 in) |
| 1979 | 119.5 mm (4.7 in) |
| 1980 | 114.5 mm (4.5 in) |
| 1981 | 127.5 mm (5.0 in) |
| 1982 | 231.7 mm (9.1 in) |
| 1983 | 161.6 mm (6.4 in) |
| 1984 | 116.8 mm (4.6 in) |
| 1985 | 71.9 mm (2.8 in) |
| 1986 | 181.7 mm (7.2 in) |
| 1987 | 88.0 mm (3.5 in) |
| 1988 | 100.8 mm (4.0 in) |
| 1989 | 58.8 mm (2.3 in) |
| 1990 | 77.0 mm (3.0 in) |
| 1991 | 92.9 mm (3.7 in) |
| 1992 | 139.7 mm (5.5 in) |
| 1993 | 101.0 mm (4.0 in) |
| 1994 | 91.7 mm (3.6 in) |
| 1995 | 142.3 mm (5.6 in) |
| 1996 | 87.7 mm (3.5 in) |
| 1997 | 133.5 mm (5.3 in) |
| 1998 | 188.0 mm (7.4 in) |
| 1999 | 111.3 mm (4.4 in) |
| 2000 | 145.5 mm (5.7 in) |
| 2001 | 77.4 mm (3.0 in) |
| 2002 | 3.3 mm (0.13 in) |
| 2003 | 79.8 mm (3.1 in) |
| 2004 | 141.7 mm (5.6 in) |
| 2005 | 105.8 mm (4.2 in) |
| 2006 | 107.4 mm (4.2 in) |
| 2007 | 78.8 mm (3.1 in) |
| 2008 | 94.3 mm (3.7 in) |
| 2009 | 127.9 mm (5.0 in) |
| 2010 | 110.7 mm (4.4 in) |
| 2011 | 74.1 mm (2.9 in) |
| 2012 | 96.3 mm (3.8 in) |
| 2013 | 31.0 mm (1.2 in) |
| 2014 | 121.2 mm (4.8 in) |
| 2015 | 81.1 mm (3.2 in) |
| 2016 | 93.2 mm (3.7 in) |
| 2017 | 103.5 mm (4.1 in) |
| 2018 | 107.0 mm (4.2 in) |
| 2019 | 66.7 mm (2.6 in) |
| 2020 | 50.8 mm (2.0 in) |
| 2021 | 183.2 mm (7.2 in) |
| 2022 | 146.2 mm (5.8 in) |
| 2023 | 117.6 mm (4.6 in) |
| 2024 | 86.2 mm (3.4 in) |
| 2025 | 93.8 mm (3.7 in) |
| 2026 | 88.4 mm (3.5 in) |
Longest dry spell (CDD)
| Year | Longest dry spell (CDD) |
|---|---|
| 1939 | 75 days |
| 1940 | 116 days |
| 1941 | 121 days |
| 1942 | 74 days |
| 1943 | 138 days |
| 1944 | 106 days |
| 1945 | 57 days |
| 1946 | 59 days |
| 1947 | 120 days |
| 1948 | 105 days |
| 1949 | 85 days |
| 1950 | 96 days |
| 1951 | 60 days |
| 1952 | 71 days |
| 1953 | 56 days |
| 1954 | 32 days |
| 1955 | 70 days |
| 1956 | 40 days |
| 1957 | 54 days |
| 1958 | 51 days |
| 1959 | 88 days |
| 1960 | 134 days |
| 1961 | 75 days |
| 1962 | 66 days |
| 1963 | 124 days |
| 1964 | 141 days |
| 1965 | 88 days |
| 1966 | 80 days |
| 1967 | 119 days |
| 1968 | 79 days |
| 1969 | 94 days |
| 1970 | 131 days |
| 1971 | 32 days |
| 1972 | 102 days |
| 1973 | 79 days |
| 1974 | 49 days |
| 1975 | 48 days |
| 1976 | 47 days |
| 1977 | 52 days |
| 1978 | 172 days |
| 1979 | 74 days |
| 1980 | 53 days |
| 1981 | 77 days |
| 1982 | 59 days |
| 1983 | 59 days |
| 1984 | 43 days |
| 1985 | 42 days |
| 1986 | 55 days |
| 1987 | 50 days |
| 1988 | 65 days |
| 1989 | 37 days |
| 1990 | 39 days |
| 1991 | 27 days |
| 1992 | 54 days |
| 1993 | 46 days |
| 1994 | 42 days |
| 1995 | 59 days |
| 1996 | 68 days |
| 1997 | 46 days |
| 1998 | 83 days |
| 1999 | 48 days |
| 2000 | 32 days |
| 2001 | 34 days |
| 2002 | 18 days |
| 2003 | 50 days |
| 2004 | 51 days |
| 2005 | 76 days |
| 2006 | 91 days |
| 2007 | 59 days |
| 2008 | 64 days |
| 2009 | 40 days |
| 2010 | 42 days |
| 2011 | 39 days |
| 2012 | 72 days |
| 2013 | 50 days |
| 2014 | 53 days |
| 2015 | 73 days |
| 2016 | 53 days |
| 2017 | 65 days |
| 2018 | 65 days |
| 2019 | 56 days |
| 2020 | 89 days |
| 2021 | 77 days |
| 2022 | 47 days |
| 2023 | 27 days |
| 2024 | 86 days |
| 2025 | 29 days |
| 2026 | 38 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.
Rainfall Return Levels
78 years, 1940 to 2025A day with at least 51.7 mm (2.0 in) of rain is expected about once in 2 years. A day with at least 133.4 mm (5.3 in) of rain is expected about once in 100 years.
| Expected about once in | A day with at least | Note |
|---|---|---|
| 2 years | 51.7 mm (2.0 in) | |
| 5 years | 69.4 mm (2.7 in) | |
| 10 years | 82.6 mm (3.3 in) | |
| 25 years | 101.3 mm (4.0 in) | |
| 50 years | 116.7 mm (4.6 in) | |
| 100 years | 133.4 mm (5.3 in) | Longer than the 78 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, 78 years of values from 1940 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: 136.7 mm (5.4 in) in 2021; 135.4 mm (5.3 in) in 1982; 124.5 mm (4.9 in) in 1962.
Station Changes
1 suspectedOne change was suspected in the annual mean temperature of Half Moon Bay, at 1969. Each is measured against neighbouring stations.
- Relative to 5 neighbouring stations, the station's annual mean temperature from 1969 ran 0.4 C (0.7 F) lower than in the years before (likely change).
| Year | Shift (C) | Shift (F) | Strength | Neighbours |
|---|---|---|---|---|
| 1969 | -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
2011 to 2025 against 1961 to 1990Over 2011 to 2025, Half Moon Bay had a mean temperature of 12.9 C (55.2 F) and 545.1 mm (21.5 in) of rain a year. The 3 stations whose 1961 to 1990 climate was closest to that are Monterey (United States, 111 km away), Morro Bay Fire Dept (United States, 274 km away) and Carmel Valley (United States, 127 km away).
| Twin station | Country | Distance away | Mean temperature, 1961-1990 | Rain a year, 1961-1990 | Climate difference |
|---|---|---|---|---|---|
| Monterey | United States | 111 km (69 mi) | 13.7 C (56.6 F) | 475.6 mm (18.7 in) | 0.98 |
| Morro Bay Fire Dept | United States | 274 km (170 mi) | 13.4 C (56.1 F) | 405.3 mm (16.0 in) | 0.98 |
| Carmel Valley | United States | 127 km (79 mi) | 13.9 C (57.1 F) | 410.0 mm (16.1 in) | 1.55 |
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 2026-10-17 (17 October 2026). Records are computed by this site and are not official.
Data as of . Last revised (2026-10-17).