Cayey climate — normals and trends
Cayey (Puerto Rico) has a tropical savanna climate (Aw) under the Köppen-Geiger classification. Its mean annual temperature is 24.6 °C and it receives 947 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 (26.0 °C on average) and the coldest is January (23.1 °C). Rainfall peaks in September.
Cayey averages 0 frost days, 2 hot days (≥ 30 °C) and 204 rainy days per year.
Cayey has warmed by +1.1 °C between 1940 and 2025, or +0.13 °C per decade. This trend is statistically significant.
The hottest day of the period reached 31.9 °C (on 11 August 1995) and the coldest 17.5 °C (on 16 February 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
CayeyCayey
- coords
- 18.11°, -66.17°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
24.6°C
Average daily high
27.0°C
Average daily low
22.7°C
Annual rainfall
947mm
Sunshine / day
11.3h
Mean relative humidity
81%
Average peak wind
19.6km/h
Seasonal range
2.9°C
Frost days (< 0 °C)
0 d/yr
Hot days (≥ 30 °C)
2 d/yr
Rainy days (≥ 1 mm)
204 d/yr
Annual snowfall
0.0 cm
Average feels-like high
30.0 °C
Average feels-like low
24.9 °C
Average peak gust
37.5 km/h
Tropical nights (≥ 20 °C)
356 d/yr
Solar radiation
20.7 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+1.1 °C
since 1940
+0.1 °C per decade · r² = 0.66 · 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
31.9 °C
11 August 1995
Coldest day
17.5 °C
16 February 1951
Wettest day
211 mm
11 May 1986
Windiest day
69.2 km/h
20 September 2017
Strongest gust
135.7 km/h
20 September 2017
Hottest feels-like
37.5 °C
29 September 2023
Coldest feels-like
15.1 °C
16 January 2000
Sunniest day
13.0 h
12 June 1940
Normals computed over complete calendar years 1940–2025.
A specific year
Pick a year and see how it compares to normal — warmer, drier or more extreme than usual?
Across the whole year
Month by month
| High | vs. normal | Precipitation | vs. normal | |
|---|---|---|---|---|
| Jan | 26.6 °C | +0.9 °C | 33 mm | -1 mm |
| Feb | 26.5 °C | +0.8 °C | 41 mm | +7 mm |
| Mar | 26.2 °C | +0.1 °C | 95 mm | +56 mm |
| Apr | 26.5 °C | 0.0 °C | 133 mm | +63 mm |
| May | 27.3 °C | +0.3 °C | 141 mm | +28 mm |
| Jun | 27.9 °C | +0.2 °C | 36 mm | -41 mm |
| Jul | 28.3 °C | +0.1 °C | 61 mm | -16 mm |
| Aug | 28.7 °C | +0.3 °C | 92 mm | -11 mm |
| Sep | 28.3 °C | +0.2 °C | 204 mm | +67 mm |
| Oct | 28.1 °C | +0.5 °C | 129 mm | -2 mm |
| Nov | 27.4 °C | +0.5 °C | 84 mm | -6 mm |
| Dec | 26.7 °C | +0.6 °C | 29 mm | -13 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 Cayey?
Cayey has a tropical savanna climate (Köppen Aw). Over 1940-2025, the average annual temperature is 24.6 °C and it receives 947 mm of precipitation per year.
What is the hottest day ever recorded in Cayey?
The hottest day measured in Cayey between 1940 and 2025 was 11 August 1995, reaching 31.9 °C.
What is the coldest day in Cayey?
The coldest day measured in Cayey between 1940 and 2025 was 16 February 1951, at 17.5 °C.
Does it snow in Cayey?
Almost never: Cayey sees virtually no snow, with about 0 frost days per year.
Has the climate of Cayey warmed?
Yes: Cayey warmed by +1.1 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Cayey?
The wettest day measured in Cayey between 1940 and 2025 was 11 May 1986, with 211 mm of rain in 24 hours.
What was the windiest day in Cayey?
The windiest day measured in Cayey between 1940 and 2025 was 20 September 2017, with winds reaching 69.2 km/h.
What is the warmest month in Cayey?
The warmest month in Cayey is August (26.0 °C on average); the coldest is January (23.1 °C).
How much does it rain in Cayey?
Cayey receives on average 947 mm of precipitation per year, spread over about 204 rainy days.
Is it sunny in Cayey?
Cayey gets on average 11.3 hours of sunshine per day, roughly 4,125 hours per year over 1940-2025.
Are there tropical nights in Cayey?
Yes: Cayey has on average 356 tropical nights per year (temperature staying above 20 °C), over 1940-2025.
What was the most extreme apparent temperature in Cayey?
In Cayey, between 1940 and 2025, the highest apparent temperature reached 37.5 °C on 29 September 2023, and the lowest was 15.1 °C on 16 January 2000.
Compare Cayey with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around Cayey