Normal weather for San Juan in September
It's hot in September in San Juan with an average temperature of 33°C. Temperatures this month range from a low of 32°C to a high of 34°C. At night, you can expect temperatures between 24°C and 26°C.
In September, there is an average of 155 mm of precipitation, spread over 19 days. The wind speed is around 4 Bft, mostly coming from the Southeast.
San Juan in September |
New York | ||
|---|---|---|---|
 Average Temperature |
33°C | 27°C | |
 High Temp |
34°C | 31°C | |
| Low Temp |
32°C | 21°C | |
 Total Precipitation |
155 mm | 57 mm | |
| Rainy Days |
19 days | 9 days | |
Start of September
The month of September starts in San Juan with hot temps, averaging around 33°C during the day and nights around 25°C. There are plenty of days with a good chance of precipitation. Light clothing like shorts or a dress, and a hat and sunglasses are perfect.
Mid September
By mid-September, daytime temps rise to around 34°C, with nights around 25°C. During this part of the month, you might see regular precipitation, but there will also be some sunny days. Light clothing like shorts or a dress, and a hat and sunglasses are perfect.
End of September
By the end of September, the average daytime temperature in San Juan is around 33°C, while nighttime temps are about 25°C. There’s a significant chance of many days with precipitation. Light clothing like shorts or a dress, and a hat and sunglasses are perfect.
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UV index
The UV index is a maximum of 9 this month. That's a very high value on the intensity scale of 1 to 11. Unprotected skin can burn within 10-15 minutes.
Is September a good time to visit San Juan?
Looking for sun? September isn’t a good month to be in San Juan. The temperature is nice, but there’s too much chance of rain.
The hurricane season in San Juan runs from June to November.
Temperature records for San Juan in September
Check out the climate of San Juan for all months and discover the best travel time
August
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Daily Temperature in September in San Juan
This chart shows the average daily high and low temperatures in September for San Juan, in degrees Celsius. The red line represents the highs, and the blue line shows the lows. The days of the month are displayed at the bottom of the chart. The data, based on historical observations, provide the average temperatures for this month.
Daily Precipitation in September in San Juan
The chart below shows the average daily precipitation in September for San Juan, measured in millimeters over the past few years. Precipitation is always measured as water, even if it’s snow or hail. The days of the month are listed at the bottom of the chart.
A low average precipitation means that the chance of rain on that day is usually small, while a higher average suggests that it rained more often. But remember, it’s just an average, and every day can be different. Based on historical weather data for September, you can expect about 19 days of precipitation in San Juan.
Daily UV Index in September in San Juan
This chart shows the average daily UV index in September in San Juan, with the UV index ranging from 0 to a maximum of 11. The bottom of the chart shows the days of the month. Based on historical data, this chart provides an idea of the daily UV radiation levels you can expect.
Temperature in September in San Juan Over the Years
This chart shows the average temperature in September in San Juan, measured in degrees Celsius, over the past few years.
Total Precipitation in September in San Juan Over the Years
This chart shows the average precipitation in September in San Juan, measured in millimeters over the past years. Precipitation is always measured as water, whether it’s snow or hail.
Daily Climate in September for San Juan
Click on any day in September to get detailed info about the usual weather on that day in San Juan. Check out the historical temperatures and precipitation over the past 10 years on this day.
Weather experiences in September in San Juan
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Average Weather in San Juan by Month
Click on a month below to see detailed weather info for San Juan. Based on historical weather data, you can see the average temperature, precipitation, wind, and UV index for each day of the month.
