Is San Juan hot in September?
Days are typically hot at 34.2°C, while nights average 23.5°C.
United States · 1991–2020 normal
San Juan in
September.
Typical September weather in San Juan: 34.2°C by day, 23.5°C at night, 116 mm of rain over 6.7 wet days. These are measured 1991–2020 station normals, not a forecast.
Typical high34.2°C
Typical low23.5°C
Rain116 mm
Wet days6.7
In the year-round weather comparison, September scores 36 out of 100 (February leads the year at 94). Daylight is calculated as 12 h 17 from latitude 26.19°.
September at a glance
What is San Juan like in September?
Plain answers from the measured climate record—not a forecast or a promise about a particular trip.
Does it rain much?
The measured monthly average is 116 mm across about 7 wet days.
How much daylight is there?
There are about 12 h 17 between sunrise and sunset at mid-month, calculated from the place latitude.
Is September a good time to visit?
September ranks 12 of 12 in our weather comparison; February ranks first.
The evidence behind this page
One month,
from the same station.
- Place identity
- GeoNames 4726440
- NOAA station
- USW00012959 · MCALLEN MILLER INTL AP
- Station distance
- 9 km from the place centre
- Coverage
- Strong coverage · 29 usable years
- Important limit
- Historical climate is not a forecast. Nearby stations can miss mountains, coasts, and local microclimates.
Next step
Choose your month.
Then plan the details.
The weather comparison for San Juan is based on climate evidence, not payments from travel companies. Flight, accommodation and activity links will be clearly labelled when they are added; there are no booking offers on this page today.
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