San Juan weather in September 2021

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  • 30°C maximum daytime temperature in September in San Juan30
    30°C max day temperature
  • 8 hours of sunshine per day
  • 18 days with some rainfall in September in San Juan18
    18 days with some rainfall
  • 23°C minimum night-time temperature in September in San Juan23
    23°C min night temperature
  • 12 hours of daylight per day in September in San Juan12
    12 hours of daylight per day
  • High heat & humidity in September in San JuanH
    High heat & humidity
  • 188 mm monthly rainfall in September in San Juan188
    188 mm of monthly rainfall
  • UV (maximum) index 11+ (Extreme) in September in San Juan11
    11+ (Extreme) UV index
  • 29°C sea temperature in September in San Juan29
    29°C sea temperature

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The September weather guide for San Juan, Puerto Rico shows long term weather averages processed from data supplied by CRU (University of East Anglia), the Met Office & the Netherlands Meteorological Institute. Find out more about our data sources.

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How hot is it in San Juan in September?

Daytime temperatures usually reach 30°C in San Juan in September with high heat and humidity, falling to 23°C at night.

How sunny is it in San Juan in September?

There are normally 8 hours of bright sunshine each day in San Juan in September - that's 64% of daylight hours.

How warm is the sea around San Juan in September?

The average sea temperature around San Juan in September is 29°C.

Does it rain in San Juan in September?

There are usually 18 days with some rain in San Juan in September and the average monthly rainfall is 188mm.

What is the chance of a hurricane in San Juan in September?

On average 1.1 days in September in San Juan are likely to be affected by the passage of one or more tropical storms.

San Juan sunrise & sunset times for September 2021

Browse the sunrise & sunset times for San Juan in September 2021. Select a month to view San Juan sunrise & sunset times for the next twelve months.

JanFebMarAprMayJunJulAugSepOctNovDec

Date Sunrise times Sunset times
Wednesday, 1st September 2021 06:10 18:38
Wednesday, 15th September 2021 06:12 18:26
Thursday, 30th September 2021 06:15 18:13
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Metric (°C / mm)  |  Imperial (°F / inches)

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Where is hot in Puerto Rico in September for 2021/2022?

Below are average maximum temperatures at popular destinations in Puerto Rico in September. Select a destination to see more weather parameters.

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