Climate averages 1991–2020
San Juan weather
in July.
A hot, moderately wet month: one of the warmest and the 7th driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
July is a hot month in San Juan: daytime highs average 31.5°C and nights cool to about 24.6°C. By daytime temperature it is one of the warmest months of the year.
Expect about 80 mm of rain on roughly 16 days, which makes July a moderately wet month (the 7th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 13 h 07 min on an average July day.
The nearest other city in this atlas is Bayamón (9 km away). In July its highs average 31.5°C, about as warm as San Juan, with 66 mm of rain.
Among the 7 cities listed in Puerto Rico, San Juan ranks joint 2nd of 7 for the warmest July highs and joint 5th of 7 for the driest July (rainfall, lowest first). The mean July high of those 7 cities is 31.1°C; San Juan is 0.3°C warmer than that mean.
From July to August, average highs rise by 0.1°C to 31.5°C, and monthly rainfall rises from 80 mm to 95 mm.
The annual picture
July in context
Monthly rainfall
Average total · mmAverages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated
Every month, side by side
San Juan climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 28.0°C21.5°C | 21.5°C | 39 | 10.4 | 11.211 h |
| February | 28.6°C21.3°C | 21.3°C | 29 | 7.7 | 11.512 h |
| March | 29.3°C21.5°C | 21.5°C | 39 | 8.4 | 12.012 h |
| April | 30.0°C22.3°C | 22.3°C | 72 | 11.0 | 12.613 h |
| May | 30.4°C23.4°C | 23.4°C | 112 | 16.1 | 13.013 h |
| June | 31.3°C24.3°C | 24.3°C | 68 | 13.8 | 13.213 h |
| July, selected | 31.5°C24.6°C | 24.6°C | 80 | 16.4 | 13.113 h |
| August | 31.5°C24.7°C | 24.7°C | 95 | 18.7 | 12.813 h |
| September | 31.2°C24.5°C | 24.5°C | 131 | 20.8 | 12.312 h |
| October | 30.4°C24.1°C | 24.1°C | 124 | 20.5 | 11.712 h |
| November | 28.9°C23.2°C | 23.2°C | 112 | 18.2 | 11.311 h |
| December | 28.1°C22.1°C | 22.1°C | 48 | 12.2 | 11.011 h |
Rainfall is the average of the 30 separate monthly totals. A rain day is a local calendar day with at least 1 mm of precipitation. Daylight is the calculated sunrise-to-sunset length, not measured sunshine.
Compare places
July in nearby cities
- Bayamón in JulyPuerto Rico · 9 kmHigh 31.5°C · Low 24.6°C · 66 mm rain
- Carolina in JulyPuerto Rico · 18 kmHigh 31.0°C · Low 24.7°C · 80 mm rain
- Caguas in JulyPuerto Rico · 27 kmHigh 30.2°C · Low 24.6°C · 110 mm rain
- Arecibo in JulyPuerto Rico · 64 kmHigh 31.7°C · Low 24.6°C · 79 mm rain
- Ponce in JulyPuerto Rico · 75 kmHigh 30.6°C · Low 24.6°C · 55 mm rain
- Mayagüez in JulyPuerto Rico · 113 kmHigh 31.5°C · Low 25.7°C · 51 mm rain
- Punta Cana in JulyDominican Republic · 243 kmHigh 28.6°C · Low 26.0°C · 90 mm rain
- Salvaleón de Higüey in JulyDominican Republic · 275 kmHigh 30.2°C · Low 24.4°C · 72 mm rain
Read the numbers correctly
Climate, not a promise.
These patterns help compare months. They cannot tell you the weather on a specific day of your trip.
Sources, method and limitsHow these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for San Juan) is explained once on the San Juan year overview and on the Sources, method and limits page.
Carolina lies in the same rainfall cell, so its rainfall figures are identical to these; temperatures differ because they come from smaller 0.1° cells.