Climate Trends in Puerto Rico [United States]
Long-record stations in Puerto Rico [United States] warmed +0.13 C per decade from 1952 to 2025 (5 stations).
Data as of . Last revised (2026-10-13).
Key Facts
- From 1952 to 2025, long-record stations in Puerto Rico [United States] warmed by +0.13 C per decade (+0.24 F) (95 percent interval +0.08 to +0.19 C), from 5 stations measured against each station's own 1961-1990 mean.
- The latest year in the series for Puerto Rico [United States], 2025, was +1.02 C against the 1961-1990 mean.
- In Puerto Rico [United States] the daily minimum rose faster than the daily maximum, by 0.26 C per decade.
- Of 13 stations in Puerto Rico [United States] with at least 50 complete years of record, 4 had 2024 as their warmest year.
Warming
Puerto Rico [United States], against 1961-1990| Year | Difference from the 1961-1990 mean |
|---|---|
| 1952 | +1.38 C |
| 1953 | +0.66 C |
| 1954 | +0.23 C |
| 1955 | -0.03 C |
| 1956 | -0.47 C |
| 1957 | -0.13 C |
| 1958 | +0.02 C |
| 1959 | -0.01 C |
| 1960 | +0.28 C |
| 1961 | -0.12 C |
| 1962 | -0.01 C |
| 1963 | +0.15 C |
| 1964 | +0.01 C |
| 1965 | -0.23 C |
| 1966 | +0.41 C |
| 1967 | -0.03 C |
| 1968 | -0.09 C |
| 1969 | +0.34 C |
| 1970 | -0.13 C |
| 1971 | -0.31 C |
| 1972 | +0.05 C |
| 1973 | +0.50 C |
| 1974 | -0.30 C |
| 1975 | -0.31 C |
| 1976 | -0.35 C |
| 1977 | -0.13 C |
| 1978 | 0.00 C |
| 1979 | -0.39 C |
| 1980 | +0.59 C |
| 1981 | +0.51 C |
| 1982 | -0.09 C |
| 1983 | +0.60 C |
| 1984 | -0.17 C |
| 1985 | -0.47 C |
| 1986 | -0.13 C |
| 1987 | +0.47 C |
| 1988 | +0.11 C |
| 1989 | -0.45 C |
| 1990 | +0.10 C |
| 1991 | +0.06 C |
| 1992 | +0.06 C |
| 1993 | +0.48 C |
| 1994 | +0.62 C |
| 1995 | +0.49 C |
| 1996 | -0.05 C |
| 1997 | +0.35 C |
| 1998 | +0.59 C |
| 1999 | +0.21 C |
| 2000 | -0.06 C |
| 2001 | +0.51 C |
| 2002 | +0.66 C |
| 2003 | +0.75 C |
| 2004 | +0.17 C |
| 2005 | +1.14 C |
| 2006 | +0.59 C |
| 2007 | +0.73 C |
| 2008 | +0.28 C |
| 2009 | +0.70 C |
| 2010 | +0.77 C |
| 2011 | +0.36 C |
| 2012 | +0.52 C |
| 2013 | +0.03 C |
| 2014 | +1.15 C |
| 2015 | +1.19 C |
| 2016 | +1.25 C |
| 2017 | +0.82 C |
| 2018 | +0.58 C |
| 2019 | +0.98 C |
| 2020 | +1.09 C |
| 2021 | +0.82 C |
| 2022 | +0.59 C |
| 2023 | +1.13 C |
| 2024 | +1.48 C |
| 2025 | +1.02 C |
From 1952 to 2025, the long-record stations in Puerto Rico [United States] warmed by +0.13 C per decade (+0.24 F) (95 percent interval +0.08 to +0.19 C), from 5 stations in 1 grid cell of 5 by 5 degrees, each measured against its own 1961-1990 mean.
The latest year in the series, 2025, was +1.0 C (+1.8 F) against the 1961-1990 mean.
The five warmest years in the series are 2024 (+1.48 C), 1952 (+1.38 C), 2016 (+1.25 C), 2015 (+1.19 C) and 2014 (+1.15 C).
Trend
| Measure | Trend per decade (C) | 95% interval (C) | Years | Stations |
|---|---|---|---|---|
| Annual mean temperature | +0.13 | +0.08 to +0.19 | 1952 to 2025 | 5 |
Warmest and coolest years in the series
| Rank | Warmest year | Difference from mean | Coolest year | Difference from mean |
|---|---|---|---|---|
| 1 | 2024 | +1.48 C | 1956 | -0.47 C |
| 2 | 1952 | +1.38 C | 1985 | -0.47 C |
| 3 | 2016 | +1.25 C | 1989 | -0.45 C |
| 4 | 2015 | +1.19 C | 1979 | -0.39 C |
| 5 | 2014 | +1.15 C | 1976 | -0.35 C |
5 stations in 1 grid cell of 5 by 5 degrees. Each station is compared with its own 1961-1990 mean, so stations at different heights and latitudes can be averaged. Stations are averaged within each grid cell and cells are weighted by the cosine of latitude.
Warmest Years
Puerto Rico [United States], 13 stations| Year | Stations with this as their warmest year |
|---|---|
| 1900 | 0 |
| 1901 | 0 |
| 1902 | 0 |
| 1903 | 0 |
| 1904 | 0 |
| 1905 | 0 |
| 1906 | 0 |
| 1907 | 0 |
| 1908 | 0 |
| 1909 | 0 |
| 1910 | 0 |
| 1911 | 0 |
| 1912 | 0 |
| 1913 | 0 |
| 1914 | 0 |
| 1915 | 1 |
| 1916 | 0 |
| 1917 | 0 |
| 1918 | 0 |
| 1919 | 0 |
| 1920 | 0 |
| 1921 | 0 |
| 1922 | 0 |
| 1923 | 0 |
| 1924 | 0 |
| 1925 | 0 |
| 1926 | 0 |
| 1927 | 0 |
| 1928 | 0 |
| 1929 | 0 |
| 1930 | 0 |
| 1931 | 1 |
| 1932 | 0 |
| 1933 | 0 |
| 1934 | 0 |
| 1935 | 0 |
| 1936 | 0 |
| 1937 | 0 |
| 1938 | 0 |
| 1939 | 0 |
| 1940 | 0 |
| 1941 | 0 |
| 1942 | 0 |
| 1943 | 0 |
| 1944 | 0 |
| 1945 | 0 |
| 1946 | 0 |
| 1947 | 0 |
| 1948 | 0 |
| 1949 | 0 |
| 1950 | 0 |
| 1951 | 0 |
| 1952 | 0 |
| 1953 | 0 |
| 1954 | 0 |
| 1955 | 0 |
| 1956 | 0 |
| 1957 | 0 |
| 1958 | 0 |
| 1959 | 0 |
| 1960 | 0 |
| 1961 | 0 |
| 1962 | 0 |
| 1963 | 0 |
| 1964 | 0 |
| 1965 | 0 |
| 1966 | 0 |
| 1967 | 0 |
| 1968 | 0 |
| 1969 | 0 |
| 1970 | 0 |
| 1971 | 0 |
| 1972 | 0 |
| 1973 | 0 |
| 1974 | 0 |
| 1975 | 0 |
| 1976 | 0 |
| 1977 | 0 |
| 1978 | 0 |
| 1979 | 0 |
| 1980 | 0 |
| 1981 | 0 |
| 1982 | 0 |
| 1983 | 0 |
| 1984 | 0 |
| 1985 | 0 |
| 1986 | 0 |
| 1987 | 0 |
| 1988 | 0 |
| 1989 | 0 |
| 1990 | 0 |
| 1991 | 0 |
| 1992 | 1 |
| 1993 | 0 |
| 1994 | 0 |
| 1995 | 0 |
| 1996 | 0 |
| 1997 | 0 |
| 1998 | 0 |
| 1999 | 0 |
| 2000 | 0 |
| 2001 | 0 |
| 2002 | 0 |
| 2003 | 0 |
| 2004 | 0 |
| 2005 | 1 |
| 2006 | 0 |
| 2007 | 1 |
| 2008 | 0 |
| 2009 | 0 |
| 2010 | 1 |
| 2011 | 0 |
| 2012 | 0 |
| 2013 | 1 |
| 2014 | 0 |
| 2015 | 2 |
| 2016 | 0 |
| 2017 | 0 |
| 2018 | 0 |
| 2019 | 0 |
| 2020 | 0 |
| 2021 | 0 |
| 2022 | 0 |
| 2023 | 0 |
| 2024 | 4 |
| 2025 | 0 |
Of the 13 stations in Puerto Rico [United States] with at least 50 complete years of record, 4 (30.8%) had 2024 as their warmest year on record.
The years that were the warmest on record at the most stations are 2024 (4 stations), 2015 (2 stations), 2013 (1 station), 2010 (1 station) and 2007 (1 station).
4 of the 13 stations (30.8%) had their warmest year in the 2020s. That decade is not over.
By decade
| Decade | Stations with their warmest year in it | Share of stations | Stations with one of their five warmest years in it |
|---|---|---|---|
| 1900s | 0 | 0.0% | 1 |
| 1910s | 1 | 7.7% | 3 |
| 1920s | 0 | 0.0% | 0 |
| 1930s | 1 | 7.7% | 2 |
| 1940s | 0 | 0.0% | 4 |
| 1950s | 0 | 0.0% | 1 |
| 1960s | 0 | 0.0% | 6 |
| 1970s | 0 | 0.0% | 0 |
| 1980s | 0 | 0.0% | 6 |
| 1990s | 1 | 7.7% | 13 |
| 2000s | 2 | 15.4% | 7 |
| 2010s | 4 | 30.8% | 9 |
| 2020s (to date) | 4 | 30.8% | 13 |
The set is the 13 stations with at least 50 complete years (all twelve months with 20 or more days of maximum and minimum). A station's warmest year is the one with the highest annual mean temperature, a tie going to the later year. The count describes these stations, not the whole area.
Days and Nights
Puerto Rico [United States], against 1961-1990| Year | Daily maximum | Daily minimum | Day-night range (maximum minus minimum) |
|---|---|---|---|
| 1952 | +2.07 C | +0.69 C | +1.38 C |
| 1953 | +1.46 C | -0.14 C | +1.59 C |
| 1954 | +0.59 C | -0.13 C | +0.71 C |
| 1955 | -0.03 C | -0.03 C | 0.00 C |
| 1956 | -0.67 C | -0.27 C | -0.39 C |
| 1957 | -0.19 C | -0.07 C | -0.11 C |
| 1958 | -0.26 C | +0.29 C | -0.54 C |
| 1959 | +0.07 C | -0.08 C | +0.15 C |
| 1960 | +0.37 C | +0.19 C | +0.18 C |
| 1961 | +0.06 C | -0.29 C | +0.34 C |
| 1962 | +0.21 C | -0.22 C | +0.44 C |
| 1963 | +0.27 C | +0.03 C | +0.24 C |
| 1964 | +0.13 C | -0.12 C | +0.25 C |
| 1965 | -0.62 C | +0.17 C | -0.80 C |
| 1966 | +0.15 C | +0.67 C | -0.52 C |
| 1967 | -0.11 C | +0.06 C | -0.17 C |
| 1968 | +0.08 C | -0.26 C | +0.34 C |
| 1969 | +0.36 C | +0.32 C | +0.04 C |
| 1970 | -0.18 C | -0.09 C | -0.09 C |
| 1971 | 0.00 C | -0.62 C | +0.62 C |
| 1972 | +0.03 C | +0.06 C | -0.03 C |
| 1973 | +0.23 C | +0.77 C | -0.54 C |
| 1974 | -0.21 C | -0.39 C | +0.17 C |
| 1975 | -0.22 C | -0.40 C | +0.18 C |
| 1976 | -0.32 C | -0.37 C | +0.05 C |
| 1977 | +0.01 C | -0.28 C | +0.29 C |
| 1978 | -0.08 C | +0.07 C | -0.15 C |
| 1979 | -0.54 C | -0.24 C | -0.30 C |
| 1980 | +0.57 C | +0.60 C | -0.03 C |
| 1981 | +0.60 C | +0.43 C | +0.17 C |
| 1982 | +0.33 C | -0.52 C | +0.84 C |
| 1983 | +0.87 C | +0.34 C | +0.53 C |
| 1984 | +0.04 C | -0.38 C | +0.42 C |
| 1985 | -0.40 C | -0.53 C | +0.13 C |
| 1986 | -0.25 C | -0.01 C | -0.24 C |
| 1987 | +0.18 C | +0.75 C | -0.57 C |
| 1988 | -0.26 C | +0.47 C | -0.74 C |
| 1989 | -0.53 C | -0.37 C | -0.17 C |
| 1990 | -0.05 C | +0.25 C | -0.30 C |
| 1991 | -0.06 C | +0.18 C | -0.24 C |
| 1992 | -0.27 C | +0.39 C | -0.67 C |
| 1993 | +0.27 C | +0.69 C | -0.42 C |
| 1994 | +0.67 C | +0.57 C | +0.11 C |
| 1995 | +0.64 C | +0.34 C | +0.30 C |
| 1996 | -0.44 C | +0.33 C | -0.77 C |
| 1997 | -0.05 C | +0.75 C | -0.80 C |
| 1998 | 0.00 C | +1.18 C | -1.18 C |
| 1999 | -0.39 C | +0.81 C | -1.20 C |
| 2000 | -0.23 C | +0.11 C | -0.34 C |
| 2001 | +0.25 C | +0.78 C | -0.53 C |
| 2002 | +0.38 C | +0.94 C | -0.56 C |
| 2003 | +0.24 C | +1.27 C | -1.03 C |
| 2004 | -0.35 C | +0.69 C | -1.05 C |
| 2005 | +0.35 C | +1.93 C | -1.58 C |
| 2006 | +0.20 C | +0.98 C | -0.77 C |
| 2007 | +0.36 C | +1.11 C | -0.75 C |
| 2008 | -0.13 C | +0.69 C | -0.82 C |
| 2009 | +0.36 C | +1.04 C | -0.68 C |
| 2010 | +0.20 C | +1.34 C | -1.14 C |
| 2011 | +0.09 C | +0.63 C | -0.54 C |
| 2012 | +0.24 C | +0.80 C | -0.56 C |
| 2013 | +0.25 C | -0.19 C | +0.45 C |
| 2014 | +0.51 C | +1.79 C | -1.28 C |
| 2015 | +0.61 C | +1.76 C | -1.16 C |
| 2016 | +0.59 C | +1.91 C | -1.32 C |
| 2017 | +0.36 C | +1.27 C | -0.91 C |
| 2018 | -0.50 C | +1.66 C | -2.16 C |
| 2019 | +0.08 C | +1.89 C | -1.82 C |
| 2020 | +0.24 C | +1.93 C | -1.69 C |
| 2021 | +0.20 C | +1.44 C | -1.24 C |
| 2022 | -0.13 C | +1.32 C | -1.45 C |
| 2023 | +0.51 C | +1.75 C | -1.25 C |
| 2024 | +0.75 C | +2.20 C | -1.45 C |
| 2025 | +0.26 C | +1.77 C | -1.51 C |
From 1952 to 2025, the daily maximum in Puerto Rico [United States] changed by 0.00 C per decade (+0.01 F) (95 percent interval -0.07 to +0.08 C) and the daily minimum by +0.26 C per decade (+0.48 F) (95 percent interval +0.19 to +0.33 C), from 5 stations.
The daily minimum rose faster, by 0.26 C per decade more than the daily maximum; the two intervals do not overlap.
The day-night range (daily maximum minus daily minimum) changed by -0.26 C per decade (95 percent interval -0.35 to -0.17 C), which means the range narrowed.
Trends per decade
| Measure | Trend per decade (C) | 95% interval (C) | Years | Stations |
|---|---|---|---|---|
| Daily maximum | 0.00 | -0.07 to +0.08 | 1952 to 2025 | 5 |
| Daily minimum | +0.26 | +0.19 to +0.33 | 1952 to 2025 | 5 |
| Day-night range (maximum minus minimum) | -0.26 | -0.35 to -0.17 | 1952 to 2025 | 5 |
The day-night range is the daily maximum minus the daily minimum, so a falling range means the minimum rose by more than the maximum. Intervals allow for year to year persistence in the series.
Heavy Rain and Dry Spells by Decade: Puerto Rico [United States]
15 stations in the annual rain series- In Puerto Rico [United States], annual rain at 15 stations is shown as a percent difference from each station's own 1961-1990 mean, for 74 years from 1952 to 2025.
- The trend in annual rain is +0.7 percent per decade (95 percent interval -1.1 to +2.5), fitted to 74 years from 1952 to 2025. The interval includes zero, so the series does not separate a trend from year to year variation.
Annual rain against the 1961-1990 mean
| Year | Annual rain, percent difference from the mean |
|---|---|
| 1952 | 12.1% |
| 1953 | -4.8% |
| 1954 | 9.8% |
| 1955 | -10.2% |
| 1956 | 14.4% |
| 1957 | -19.6% |
| 1958 | 11.7% |
| 1959 | -2.8% |
| 1960 | 21.2% |
| 1961 | 10.2% |
| 1962 | -3.6% |
| 1963 | 7.0% |
| 1964 | -22.2% |
| 1965 | 7.2% |
| 1966 | 0.0% |
| 1967 | -26.2% |
| 1968 | -7.3% |
| 1969 | 14.4% |
| 1970 | 27.7% |
| 1971 | -9.2% |
| 1972 | -14.4% |
| 1973 | -20.1% |
| 1974 | 3.8% |
| 1975 | -5.9% |
| 1976 | -24.0% |
| 1977 | -6.5% |
| 1978 | 1.4% |
| 1979 | 33.7% |
| 1980 | -19.3% |
| 1981 | 25.4% |
| 1982 | -1.9% |
| 1983 | -14.8% |
| 1984 | -1.2% |
| 1985 | 6.6% |
| 1986 | 4.5% |
| 1987 | 21.2% |
| 1988 | 6.6% |
| 1989 | -11.1% |
| 1990 | 6.5% |
| 1991 | -21.9% |
| 1992 | -1.5% |
| 1993 | -13.0% |
| 1994 | -25.9% |
| 1995 | -5.1% |
| 1996 | 3.5% |
| 1997 | -27.7% |
| 1998 | 26.7% |
| 1999 | 5.9% |
| 2000 | -19.1% |
| 2001 | -0.8% |
| 2002 | -19.9% |
| 2003 | 19.0% |
| 2004 | 12.2% |
| 2005 | 26.2% |
| 2006 | 7.2% |
| 2007 | 9.0% |
| 2008 | 6.9% |
| 2009 | -3.9% |
| 2010 | 40.7% |
| 2011 | 36.6% |
| 2012 | 3.8% |
| 2013 | 10.2% |
| 2014 | -9.5% |
| 2015 | -29.0% |
| 2016 | 19.9% |
| 2017 | 34.1% |
| 2018 | -4.0% |
| 2019 | -12.3% |
| 2020 | 8.6% |
| 2021 | -17.0% |
| 2022 | 8.4% |
| 2023 | -13.6% |
| 2024 | 18.3% |
| 2025 | -2.8% |
The annual rain series uses stations with at least 50 complete years since 1951 and a 1961-1990 baseline. The decade charts use fixed sets of stations, the same in every decade from the 1960s. A dry day has less than 1 mm (0.04 in) of rain.
Longest Hot, Cold, Wet and Dry Streaks: Puerto Rico [United States]
4 lists of 10- In Puerto Rico [United States], the longest run of hot days in a row in the data is 38 days, at San German 4 W (Puerto Rico [United States]), from 9 July 1957 to 15 August 1957.
- In Puerto Rico [United States], the longest run of dry days in a row in the data is 165 days, at Caguas (Puerto Rico [United States]), in 1947.
- In Puerto Rico [United States], the longest run of wet days in a row in the data is 94 days, at Pico del Este (Puerto Rico [United States]), in 1999.
- In Puerto Rico [United States], the longest run of longest run of nights at or above 25 c in the data is 178 days, at San Juan L M Marin Intl AP (Puerto Rico [United States]), from 5 May 2024 to 29 October 2024.
Longest run of days at or above 35 C
Consecutive days with a daily maximum at or above 35 C (95 F).
| Rank | Station | Country | Length | When |
|---|---|---|---|---|
| 1 | San German 4 W | Puerto Rico [United States] | 38 days | 9 July to 15 August 1957 |
| 2 | Mona Island 2 | Puerto Rico [United States] | 21 days | 29 September to 19 October 1997 |
| 3 | Mayaguez City | Puerto Rico [United States] | 20 days | 4 to 23 September 1924 |
| 4 | San Sebastian 2 WNW | Puerto Rico [United States] | 19 days | 2 to 20 August 1993 |
| 5 | Dos Bocas | Puerto Rico [United States] | 15 days | 7 to 21 June 2023 |
| 6 | Manati 2 E | Puerto Rico [United States] | 10 days | 16 to 25 June 1903 |
| 7 | Arecibo Obsy | Puerto Rico [United States] | 8 days | 10 to 17 June 2023 |
| 8 | Isabela Substn | Puerto Rico [United States] | 7 days | 16 to 22 October 1911 |
| 9 | Juncos 1 SE | Puerto Rico [United States] | 7 days | 3 to 9 July 1938 |
| 10 | Patillas Dam | Puerto Rico [United States] | 7 days | 13 to 19 September 1945 |
Longest dry spell (days under 1 mm of rain), within one year
Consecutive days with less than 1 mm (0.04 in) of rain, the longest run within a year. The dates are not kept, so the list gives the year (within the year).
| Rank | Station | Country | Length | When |
|---|---|---|---|---|
| 1 | Caguas | Puerto Rico [United States] | 165 days | within 1947 |
| 2 | Aguirre | Puerto Rico [United States] | 144 days | within 1999 |
| 3 | Mayaguez City | Puerto Rico [United States] | 134 days | within 2012 |
| 4 | Coamo 2 SW | Puerto Rico [United States] | 117 days | within 1984 |
| 5 | Hacienda Constanza | Puerto Rico [United States] | 102 days | within 2006 |
| 6 | Puerto Real | Puerto Rico [United States] | 97 days | within 1977 |
| 7 | Cambalache Exp Forest | Puerto Rico [United States] | 92 days | within 1958 |
| 8 | Ponce 4 E | Puerto Rico [United States] | 90 days | within 1970 |
| 9 | Ensenada 1 W | Puerto Rico [United States] | 86 days | within 1975 |
| 10 | Santa Rita | Puerto Rico [United States] | 82 days | within 1958 |
Longest wet spell (days with 1 mm or more of rain), within one year
Consecutive days with 1 mm (0.04 in) or more of rain, the longest run within a year. The dates are not kept, so the list gives the year (within the year).
| Rank | Station | Country | Length | When |
|---|---|---|---|---|
| 1 | Pico del Este | Puerto Rico [United States] | 94 days | within 1999 |
| 2 | San Lorenzo 1SW | Puerto Rico [United States] | 85 days | within 2005 |
| 3 | Paraiso | Puerto Rico [United States] | 63 days | within 1981 |
| 4 | Caguas | Puerto Rico [United States] | 58 days | within 1912 |
| 5 | Rio Grande El Verde | Puerto Rico [United States] | 52 days | within 1962 |
| 6 | Rio Blanco Lower | Puerto Rico [United States] | 45 days | within 2006 |
| 7 | Canovanas | Puerto Rico [United States] | 43 days | within 1989 |
| 8 | Lares | Puerto Rico [United States] | 36 days | within 1965 |
| 9 | Cidra 1 E | Puerto Rico [United States] | 30 days | within 1937 |
| 10 | Humacao 2 SSE | Puerto Rico [United States] | 29 days | within 1936 |
Longest run of nights at or above 25 C
| Rank | Station | Country | Length | When |
|---|---|---|---|---|
| 1 | San Juan L M Marin Intl AP | Puerto Rico [United States] | 178 days | 5 May to 29 October 2024 |
| 2 | Aguirre | Puerto Rico [United States] | 62 days | 23 June to 23 August 1949 |
| 3 | Magueyes Is | Puerto Rico [United States] | 41 days | 12 July to 21 August 2023 |
| 4 | Roosevelt Roads | Puerto Rico [United States] | 39 days | 7 July to 14 August 1987 |
| 5 | Guayama 1SW | Puerto Rico [United States] | 33 days | 29 May to 30 June 2015 |
| 6 | Fajardo | Puerto Rico [United States] | 29 days | 27 September to 25 October 1944 |
| 7 | Aguirre | Puerto Rico [United States] | 27 days | 18 June to 14 July 2024 |
| 8 | Manati 2 E | Puerto Rico [United States] | 21 days | 10 to 30 June 1914 |
| 9 | Mayaguez City | Puerto Rico [United States] | 18 days | 26 October to 12 November 2012 |
| 10 | Dorado 2 WNW | Puerto Rico [United States] | 14 days | 18 to 31 May 1950 |
A run belongs to the year it started in, even when it ran on into the next year. A station appears once per list, with its longest run in a complete year. Dry and wet spells are the longest run within a year. Lists use complete years only, so a long run in a year with gaps in the record is not counted.
Biggest One Day Temperature Swings: Puerto Rico [United States]
5 lists of 10- In Puerto Rico [United States], the largest reported one day rise in the daily maximum is 13.3 C (23.9 F), at Aibonito 1 S (Puerto Rico [United States]) on 12 April 1915.
- In Puerto Rico [United States], the largest reported one day drop in the daily maximum is 13.3 C (23.9 F), at Maricao 2 SSW (Puerto Rico [United States]) on 30 January 2001.
- In Puerto Rico [United States], the largest reported one day rise in the daily minimum is 14.5 C (26.1 F), at Mayaguez City (Puerto Rico [United States]) on 3 February 2004.
- In Puerto Rico [United States], the largest reported one day drop in the daily minimum is 13.3 C (23.9 F), at San German 4 W (Puerto Rico [United States]) on 28 April 1928.
- In Puerto Rico [United States], the largest reported range between the high and the low of one day is 27.8 C (50.0 F), at San Sebastian 2 WNW (Puerto Rico [United States]) on 24 January 1966.
Caveat.Single readings can still be instrument errors that quality control missed. A station with one faulty value can top a list, so read each entry as a reported value, not as a confirmed event.
Biggest one day rise in the daily maximum
The largest increase in the daily maximum temperature from one day to the next. Values are in degrees Celsius with Fahrenheit beside them.
| Rank | Station | Country | Value | Date |
|---|---|---|---|---|
| 1 | Aibonito 1 S | Puerto Rico [United States] | 13.3 C (23.9 F) | 12 April 1915 |
| 2 | Garzas | Puerto Rico [United States] | 12.8 C (23.0 F) | 4 June 1953 |
| 3 | Jayuya | Puerto Rico [United States] | 12.2 C (22.0 F) | 20 September 1923 |
| 4 | Maricao 2 SSW | Puerto Rico [United States] | 11.7 C (21.1 F) | 31 January 2001 |
| 5 | Isabela Substn | Puerto Rico [United States] | 11.1 C (20.0 F) | 3 January 1945 |
| 6 | Lares | Puerto Rico [United States] | 11.1 C (20.0 F) | 5 May 1963 |
| 7 | Coloso | Puerto Rico [United States] | 11.1 C (20.0 F) | 21 February 1993 |
| 8 | Caguas | Puerto Rico [United States] | 10.6 C (19.1 F) | 18 June 1903 |
| 9 | Dos Bocas | Puerto Rico [United States] | 10.6 C (19.1 F) | 13 May 1998 |
| 10 | Arecibo Obsy | Puerto Rico [United States] | 10.5 C (18.9 F) | 8 September 2022 |
Biggest one day drop in the daily maximum
The largest decrease in the daily maximum temperature from one day to the next. Values are in degrees Celsius with Fahrenheit beside them.
| Rank | Station | Country | Value | Date |
|---|---|---|---|---|
| 1 | Maricao 2 SSW | Puerto Rico [United States] | 13.3 C (23.9 F) | 30 January 2001 |
| 2 | Jayuya | Puerto Rico [United States] | 12.8 C (23.0 F) | 19 September 1923 |
| 3 | Cerro Maravilla | Puerto Rico [United States] | 12.8 C (23.0 F) | 27 November 1986 |
| 4 | Aibonito 1 S | Puerto Rico [United States] | 12.2 C (22.0 F) | 13 April 1915 |
| 5 | Cidra 1 E | Puerto Rico [United States] | 12.2 C (22.0 F) | 3 July 1932 |
| 6 | Ponce 4 E | Puerto Rico [United States] | 12.2 C (22.0 F) | 15 August 1944 |
| 7 | Arecibo Obsy | Puerto Rico [United States] | 12.2 C (22.0 F) | 28 January 1998 |
| 8 | Corozal Substn | Puerto Rico [United States] | 12.2 C (22.0 F) | 8 March 2010 |
| 9 | Dos Bocas | Puerto Rico [United States] | 11.7 C (21.1 F) | 27 May 1994 |
| 10 | Rio Piedras | Puerto Rico [United States] | 11.1 C (20.0 F) | 24 January 1942 |
Biggest one day rise in the daily minimum
The largest increase in the daily minimum temperature from one day to the next. Values are in degrees Celsius with Fahrenheit beside them.
| Rank | Station | Country | Value | Date |
|---|---|---|---|---|
| 1 | Mayaguez City | Puerto Rico [United States] | 14.5 C (26.1 F) | 3 February 2004 |
| 2 | San German 4 W | Puerto Rico [United States] | 12.2 C (22.0 F) | 27 April 1928 |
| 3 | Isabela Substn | Puerto Rico [United States] | 12.2 C (22.0 F) | 14 June 2019 |
| 4 | Garzas | Puerto Rico [United States] | 11.7 C (21.1 F) | 25 October 1960 |
| 5 | Cerro Maravilla | Puerto Rico [United States] | 11.7 C (21.1 F) | 25 March 2003 |
| 6 | Trujillo Alto 2 SSW | Puerto Rico [United States] | 11.7 C (21.1 F) | 31 May 2017 |
| 7 | Adjuntas Substn | Puerto Rico [United States] | 11.6 C (20.9 F) | 5 March 2023 |
| 8 | Aibonito 1 S | Puerto Rico [United States] | 11.1 C (20.0 F) | 4 January 1927 |
| 9 | Lares | Puerto Rico [United States] | 11.1 C (20.0 F) | 9 January 1941 |
| 10 | Arecibo Obsy | Puerto Rico [United States] | 11.1 C (20.0 F) | 12 August 2014 |
Biggest one day drop in the daily minimum
The largest decrease in the daily minimum temperature from one day to the next. Values are in degrees Celsius with Fahrenheit beside them.
| Rank | Station | Country | Value | Date |
|---|---|---|---|---|
| 1 | San German 4 W | Puerto Rico [United States] | 13.3 C (23.9 F) | 28 April 1928 |
| 2 | Utuado | Puerto Rico [United States] | 12.8 C (23.0 F) | 19 March 1946 |
| 3 | Arecibo Obsy | Puerto Rico [United States] | 12.8 C (23.0 F) | 10 January 1999 |
| 4 | Mayaguez City | Puerto Rico [United States] | 12.2 C (22.0 F) | 21 August 1914 |
| 5 | Adjuntas Substn | Puerto Rico [United States] | 12.2 C (22.0 F) | 6 March 2023 |
| 6 | Juncos 1 SE | Puerto Rico [United States] | 11.7 C (21.1 F) | 23 October 1944 |
| 7 | Guayama 1SW | Puerto Rico [United States] | 11.6 C (20.9 F) | 19 January 1946 |
| 8 | Aibonito 1 S | Puerto Rico [United States] | 11.1 C (20.0 F) | 15 February 1906 |
| 9 | Corozal Substn | Puerto Rico [United States] | 11.1 C (20.0 F) | 30 January 1934 |
| 10 | Cerro Maravilla | Puerto Rico [United States] | 11.1 C (20.0 F) | 5 April 2005 |
Widest range between the high and the low of one day
The largest difference between the highest and the lowest temperature of the same day. Values are in degrees Celsius with Fahrenheit beside them.
| Rank | Station | Country | Value | Date |
|---|---|---|---|---|
| 1 | San Sebastian 2 WNW | Puerto Rico [United States] | 27.8 C (50.0 F) | 24 January 1966 |
| 2 | Coloso | Puerto Rico [United States] | 26.6 C (47.9 F) | 30 January 1925 |
| 3 | Caguas | Puerto Rico [United States] | 26.1 C (47.0 F) | 16 November 1902 |
| 4 | Juana Diaz Camp | Puerto Rico [United States] | 25.6 C (46.1 F) | 8 January 1945 |
| 5 | Utuado | Puerto Rico [United States] | 25.6 C (46.1 F) | 19 March 1946 |
| 6 | Rincon | Puerto Rico [United States] | 25.0 C (45.0 F) | 23 March 1985 |
| 7 | Mayaguez City | Puerto Rico [United States] | 25.0 C (45.0 F) | 2 February 2004 |
| 8 | Gurabo Substn | Puerto Rico [United States] | 24.5 C (44.1 F) | 4 March 1996 |
| 9 | Cidra 1 E | Puerto Rico [United States] | 23.9 C (43.0 F) | 11 February 1907 |
| 10 | Juncos 1 SE | Puerto Rico [United States] | 23.9 C (43.0 F) | 13 April 1953 |
Only stations with at least 10 complete years are listed, and a station appears once per list.
Hot and Dry Summers: Puerto Rico [United States]
22 stations with a 1961-1990 record- In Puerto Rico [United States], the share of stations with a hot and dry summer is shown for each year from 1941 to 2012, for 22 stations with at least 20 complete summers in 1961-1990. Each year counts the stations of that set with a complete summer in the year.
- In Puerto Rico [United States], 5.4% of station summers in 1961-1990 were hot and dry (559 station summers).
- In Puerto Rico [United States], 5.3% of station summers in 1998-2012 were hot and dry (131 station summers).
- In Puerto Rico [United States], 1994 had the highest share: 50.0% of 20 stations (10).
A summer is hot when its mean daily maximum is at or above the station's 80th percentile of its 1961-1990 summers, and dry when its rain is at or below the 20th percentile. A summer is hot and dry when it is both. Summer is June to August north of the equator and December to February south of it, labelled by the year of its first month.
Share of stations with a hot and dry summer
| Summer | Stations with a hot and dry summer |
|---|---|
| 1941 | 0.0% |
| 1942 | 0.0% |
| 1954 | 0.0% |
| 1955 | 0.0% |
| 1956 | 0.0% |
| 1957 | 6.7% |
| 1958 | 0.0% |
| 1959 | 0.0% |
| 1960 | 0.0% |
| 1961 | 0.0% |
| 1962 | 0.0% |
| 1963 | 0.0% |
| 1964 | 0.0% |
| 1965 | 0.0% |
| 1966 | 5.9% |
| 1967 | 6.3% |
| 1968 | 0.0% |
| 1969 | 0.0% |
| 1970 | 0.0% |
| 1971 | 0.0% |
| 1972 | 0.0% |
| 1973 | 0.0% |
| 1974 | 9.5% |
| 1975 | 9.1% |
| 1976 | 0.0% |
| 1977 | 0.0% |
| 1978 | 0.0% |
| 1979 | 0.0% |
| 1980 | 33.3% |
| 1981 | 0.0% |
| 1982 | 10.0% |
| 1983 | 15.8% |
| 1984 | 0.0% |
| 1985 | 41.2% |
| 1986 | 17.6% |
| 1987 | 5.3% |
| 1988 | 0.0% |
| 1989 | 4.8% |
| 1990 | 5.3% |
| 1991 | 21.1% |
| 1992 | 12.5% |
| 1993 | 15.0% |
| 1994 | 50.0% |
| 1995 | 0.0% |
| 1996 | 5.9% |
| 1997 | 33.3% |
| 1998 | 0.0% |
| 1999 | 0.0% |
| 2000 | 10.0% |
| 2001 | 16.7% |
| 2002 | 8.3% |
| 2003 | 8.3% |
| 2004 | 0.0% |
| 2006 | 0.0% |
| 2010 | 0.0% |
| 2011 | 0.0% |
| 2012 | 16.7% |
The ten most extreme station summers
| Rank | Station | Country | Summer | Mean daily maximum vs 1961-1990 | Rain, percent of 1961-1990 mean |
|---|---|---|---|---|---|
| 1 | Isabela Substn | Puerto Rico [United States] | 1918 | +4.0 C (+7.2 F) | 52% |
| 2 | Gurabo Substn | Puerto Rico [United States] | 2012 | +2.7 C (+4.8 F) | 87% |
| 3 | Isabela Substn | Puerto Rico [United States] | 1915 | +3.0 C (+5.5 F) | 40% |
| 4 | Isabela Substn | Puerto Rico [United States] | 1917 | +3.3 C (+5.9 F) | 75% |
| 5 | Gurabo Substn | Puerto Rico [United States] | 2014 | +2.1 C (+3.7 F) | 84% |
| 6 | Gurabo Substn | Puerto Rico [United States] | 2008 | +1.7 C (+3.1 F) | 60% |
| 7 | Gurabo Substn | Puerto Rico [United States] | 2015 | +1.3 C (+2.4 F) | 29% |
| 8 | Isabela Substn | Puerto Rico [United States] | 1911 | +2.5 C (+4.5 F) | 63% |
| 9 | Isabela Substn | Puerto Rico [United States] | 1923 | +1.6 C (+2.8 F) | 36% |
| 10 | Lajas Substn | Puerto Rico [United States] | 1997 | +2.0 C (+3.5 F) | 47% |
Ranked by the temperature z score minus the rain z score against the station's own 1961-1990 mean and standard deviation (at least 0.3 C and 5 mm). A summer is labelled by the year of its first month.
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. Trends and counts are computed by this site from daily station records. The long-record station set is described under each chart.