September Weather in Palo Alto, Mexico

Last updated: August 27, 2025

In September, the average temperature in Palo Alto, Mexico is a pleasant 21°C (69°F), with lows reaching 16°C (61°F) and highs climbing to 28°C (82°F). Expect 199 mm (7.8 in) of precipitation spread over 24 days, contributing to an average humidity of 84%. Ideal for those who love a lush, vibrant atmosphere!

September Temperature in Palo Alto

In September in Palo Alto, the average temperature is 21°C (69°F). Maximum temperatures can reach 28°C (82°F), while the minimum can drop to as low as 16°C (61°F). This mild climate makes Palo Alto an ideal destination for travelers looking to enjoy comfortable weather.

September Weather in Palo Alto: Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in Palo Alto, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Palo Alto, September typically has an average temperature of 21°C (69°F), with highs reaching up to 28°C (82°F) and lows dropping to around 16°C (61°F).

Data source: Temperature data for Palo Alto generated using information from the Copernicus Climate Change Service.

September Precipitation in Palo Alto

In Palo Alto in September, the precipitation amount is 199 mm (7.8 in) over the course of 24 days.

September Precipitation Trends in Palo Alto

The chart displays monthly precipitation patterns in Palo Alto, 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 Palo Alto, September typically receives around 199 mm (7.8 inches) of precipitation spread over approximately 24 days.

Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.

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Millimeters (mm) Inches (in)

September Humidity in Palo Alto

In Palo Alto in September, humidity is 84%. With an average temperature of 21°C (69°F), this humidity feels like a thick blanket enveloping you, making even the simplest outdoor activities feel exhausting and sticky, which can be quite challenging for traveling.

September Average Humidity in Palo Alto

This chart illustrates the average monthly humidity levels in Palo Alto, 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 Palo Alto is approximately 84%, offering insight into how humid the weather typically is during this month.

Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Palo Alto

In Palo Alto in September, the maximum UV index is 14, which corresponds to an extreme Exposure Category. The time to burn is just 10 minutes, so it's crucial to take precautions. For the detailed hourly UV index in Palo Alto, you can check here.

Maximum UV Index Levels in Palo Alto for September

The chart shows the monthly maximum UV Index (UVI) for Palo Alto 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 Palo Alto typically reaches 14, which falls under the extreme exposure category.

Data source: Palo Alto 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 Palo Alto Compares to Other Months

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

This table compares monthly weather conditions in Palo Alto, showing how September’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	17°C (62°F)	9 mm (0.4 inches)	64%	very high
February Weather	18°C (65°F)	14 mm (0.5 inches)	57%	extreme
March Weather	21°C (70°F)	6 mm (0.2 inches)	46%	extreme
April Weather	22°C (72°F)	1 mm (0.0 inches)	42%	extreme
May Weather	23°C (74°F)	27 mm (1.0 inches)	51%	extreme
June Weather	22°C (72°F)	135 mm (5.3 inches)	74%	extreme
July Weather	21°C (70°F)	204 mm (8.0 inches)	79%	extreme
August Weather	21°C (70°F)	209 mm (8.2 inches)	81%	extreme
September Weather	21°C (69°F)	199 mm (7.8 inches)	84%	extreme
October Weather	20°C (69°F)	71 mm (2.8 inches)	75%	extreme
November Weather	19°C (66°F)	25 mm (1.0 inches)	71%	very high
December Weather	17°C (63°F)	5 mm (0.2 inches)	74%	very high