Bayamón climate — normals and trends
Bayamón (Puerto Rico) has a tropical savanna climate (Aw) under the Köppen-Geiger classification. Its mean annual temperature is 25.8 °C and it receives 891 mm of precipitation per year.
These figures are normals computed over 86 complete calendar years, from 1940 to 2025, using ERA5 reanalysis data from the Copernicus programme.
The warmest month is August (27.3 °C on average) and the coldest is January (24.2 °C). Rainfall peaks in October.
Bayamón averages 0 frost days, 83 hot days (≥ 30 °C) and 184 rainy days per year.
Bayamón has warmed by +1.3 °C between 1940 and 2025, or +0.16 °C per decade. This trend is statistically significant.
The hottest day of the period reached 33.5 °C (on 10 October 2024) and the coldest 18.6 °C (on 12 March 1951).
Data from ERA5 reanalysis (Copernicus Climate Change Service), redistributed under a CC-BY 4.0 licence. Normals are recomputed whenever the archive is updated.
Climate normals · ERA5
BayamónBayamón
- coords
- 18.40°, -66.16°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
25.8°C
Average daily high
28.6°C
Average daily low
23.8°C
Annual rainfall
891mm
Sunshine / day
11.3h
Mean relative humidity
79%
Average peak wind
19.4km/h
Seasonal range
3.1°C
Frost days (< 0 °C)
0 d/yr
Hot days (≥ 30 °C)
83 d/yr
Rainy days (≥ 1 mm)
184 d/yr
Annual snowfall
0.0 cm
Average feels-like high
32.0 °C
Average feels-like low
26.8 °C
Average peak gust
36.4 km/h
Tropical nights (≥ 20 °C)
364 d/yr
Solar radiation
20.4 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+1.3 °C
since 1940
+0.2 °C per decade · r² = 0.70 · p = < 0.001
Trend fitted by linear regression (ordinary least squares) on annual means. A trend is shown only when it is statistically significant (p < 0.05).
A climograph overlays rainfall (bars) and temperature (line): the standard reading in climatology, where you can see at a glance whether the warm season is also the dry one.
Records for the period
Hottest day
33.5 °C
10 October 2024
Coldest day
18.6 °C
12 March 1951
Wettest day
166 mm
20 September 2017
Windiest day
80.1 km/h
20 September 2017
Strongest gust
141.8 km/h
20 September 2017
Hottest feels-like
40.7 °C
24 August 2023
Coldest feels-like
17.3 °C
16 January 2000
Sunniest day
13.0 h
12 June 1940
Normals computed over complete calendar years 1940–2025.
A specific year
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Across the whole year
Month by month
| High | vs. normal | Precipitation | vs. normal | |
|---|---|---|---|---|
| Jan | 27.5 °C | +0.7 °C | 46 mm | +6 mm |
| Feb | 27.8 °C | +0.7 °C | 33 mm | -2 mm |
| Mar | 28.2 °C | +0.6 °C | 52 mm | +15 mm |
| Apr | 28.1 °C | -0.1 °C | 126 mm | +53 mm |
| May | 28.8 °C | -0.1 °C | 118 mm | +9 mm |
| Jun | 29.9 °C | +0.1 °C | 16 mm | -46 mm |
| Jul | 30.3 °C | +0.4 °C | 33 mm | -32 mm |
| Aug | 30.7 °C | +0.6 °C | 82 mm | -4 mm |
| Sep | 30.5 °C | +0.6 °C | 172 mm | +55 mm |
| Oct | 30.2 °C | +0.8 °C | 102 mm | -20 mm |
| Nov | 29.0 °C | +0.9 °C | 60 mm | -37 mm |
| Dec | 28.3 °C | +1.1 °C | 27 mm | -24 mm |
The year's extremes
What was the weather like that day?
Your birthday, a wedding, a memorable trip: discover the actual weather for any date since 1940.
Frequently asked questions
What is the climate of Bayamón?
Bayamón has a tropical savanna climate (Köppen Aw). Over 1940-2025, the average annual temperature is 25.8 °C and it receives 891 mm of precipitation per year.
What is the hottest day ever recorded in Bayamón?
The hottest day measured in Bayamón between 1940 and 2025 was 10 October 2024, reaching 33.5 °C.
What is the coldest day in Bayamón?
The coldest day measured in Bayamón between 1940 and 2025 was 12 March 1951, at 18.6 °C.
Does it snow in Bayamón?
Almost never: Bayamón sees virtually no snow, with about 0 frost days per year.
Has the climate of Bayamón warmed?
Yes: Bayamón warmed by +1.3 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Bayamón?
The wettest day measured in Bayamón between 1940 and 2025 was 20 September 2017, with 166 mm of rain in 24 hours.
What was the windiest day in Bayamón?
The windiest day measured in Bayamón between 1940 and 2025 was 20 September 2017, with winds reaching 80.1 km/h.
What is the warmest month in Bayamón?
The warmest month in Bayamón is August (27.3 °C on average); the coldest is January (24.2 °C).
How much does it rain in Bayamón?
Bayamón receives on average 891 mm of precipitation per year, spread over about 184 rainy days.
Is it sunny in Bayamón?
Bayamón gets on average 11.3 hours of sunshine per day, roughly 4,125 hours per year over 1940-2025.
Are there tropical nights in Bayamón?
Yes: Bayamón has on average 364 tropical nights per year (temperature staying above 20 °C), over 1940-2025.
What was the most extreme apparent temperature in Bayamón?
In Bayamón, between 1940 and 2025, the highest apparent temperature reached 40.7 °C on 24 August 2023, and the lowest was 17.3 °C on 16 January 2000.
Compare Bayamón with another city
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Nearby cities
The climate around Bayamón