nomadseason

September Weather in San Isidro, Peru

Last updated: August 27, 2025

In September, the average temperature in San Isidro, Peru is a mild 17°C (62°F), with minimums dropping to 14°C (57°F) and maximums reaching 20°C (69°F). Expect light showers with a precipitation amount of 10 mm (0.4 in) over just 1 day. The average humidity levels around 53% ensure a comfortably refreshing atmosphere.

September Temperature in San Isidro

In September in San Isidro, the average temperature is 17°C (62°F). Maximums can reach 20°C (69°F), while minimums can drop to as low as 14°C (57°F). This mild climate makes San Isidro an ideal destination for travelers seeking comfortable weather and outdoor activities.

September Weather in San Isidro: Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in San Isidro, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In San Isidro, September typically has an average temperature of 17°C (62°F), with highs reaching up to 20°C (69°F) and lows dropping to around 14°C (57°F).
JanFebMarAprMayJunJulAugSepOctNovDec707272696664636262636567
Data source: Temperature data for San Isidro generated using information from the Copernicus Climate Change Service.
Choose your preferred temperature unit
The average of daily temperatures (24 hours) calculated across all days in the month.

September Precipitation in San Isidro

In San Isidro in September, the precipitation amount is 10 mm (0.4 in) over the course of 1 day.

September Precipitation Trends in San Isidro

The chart displays monthly precipitation patterns in San Isidro, with values for each month alongside September’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how September’s conditions compare to those of other months. In San Isidro, September typically receives around 10 mm (0.4 inches) of precipitation spread over approximately 1 days.
JanFebMarAprMayJunJulAugSepOctNovDec4753501891011101010917
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
Choose your preferred precipitation unit

September Humidity in San Isidro

In San Isidro in September, humidity is 53%. With an average temperature of 17°C (62°F), this humidity feels like a mild and comfortable embrace, making it a pleasant experience for traveling, allowing you to explore the sights without feeling overly sticky or overly dry.

September Average Humidity in San Isidro

This chart illustrates the average monthly humidity levels in San Isidro, with September’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In September, average humidity in San Isidro is approximately 53%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec89%89%90%89%83%69%56%51%53%68%82%87%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in San Isidro

In San Isidro in September, the maximum UV index is 12, which corresponds to an extreme Exposure Category. The time to burn is just 10 minutes, underscoring the importance of sun protection. For detailed information, you can check the Hourly UV Index in San Isidro.

Maximum UV Index Levels in San Isidro for September

The chart shows the monthly maximum UV Index (UVI) for San Isidro in September, representing the highest UV radiation level. The UVI measures the intensity of ultraviolet radiation from the sun, indicating the potential risk of sunburn and UV-related health issues. In September, the maximum UV index in San Isidro typically reaches 12, which falls under the extreme exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec14141412109101112131413
Data source: San Isidro September UVI data generated using information from the Copernicus Climate Change Service.

UV Risk Categories

  •  Extreme (11+): Avoid the sun, stay in shade.
  •  Very High (8-10): Limit sun exposure.
  •  High (6-7): Use SPF 30+ and protective clothing.
  •  Moderate (3-5): Midday shade recommended.
  •  Low (0-2): No protection needed.

How September Weather in San Isidro Compares to Other Months

Weather in San Isidro varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in San Isidro, focusing on differences in temperature, rainfall, humidity, and UV levels.

This table compares monthly weather conditions in San Isidro, showing how September’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
 TemperaturePrecipitationHumidityUV
January Weather21°C (71°F)47 mm (1.9 inches)89%extreme
February Weather22°C (72°F)53 mm (2.1 inches)89%extreme
March Weather22°C (72°F)50 mm (2.0 inches)90%extreme
April Weather20°C (69°F)18 mm (0.7 inches)89%extreme
May Weather19°C (66°F)9 mm (0.4 inches)83%very high
June Weather18°C (64°F)10 mm (0.4 inches)69%very high
July Weather17°C (63°F)11 mm (0.4 inches)56%very high
August Weather17°C (62°F)10 mm (0.4 inches)50%extreme
September Weather17°C (62°F)10 mm (0.4 inches)53%extreme
October Weather17°C (63°F)10 mm (0.4 inches)68%extreme
November Weather18°C (65°F)9 mm (0.4 inches)81%extreme
December Weather20°C (68°F)17 mm (0.7 inches)87%extreme

Compare San Isidro's Climate with Cities Worldwide