September Weather in Holtville, United States

Last updated: June 24, 2025

In Holtville, United States, the average temperature in September reaches a warm 32°C (90°F). Temperatures can swing dramatically, with a minimum of 15°C (60°F) and a sizzling maximum of 50°C (123°F). Expect 9 mm (0.4 in) of precipitation spread over 1 day, while the average humidity hovers around 52%, providing a balance to the heat.

September Temperature in Holtville

In September in Holtville, the average temperature is 32°C (90°F). Maximums can reach 50°C (123°F) while minimums can drop to as low as 15°C (60°F). Travelers should be prepared for extreme heat during the day and cooler temperatures at night.

September Weather in Holtville: Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in Holtville, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Holtville, September typically has an average temperature of 32°C (90°F), with highs reaching up to 50°C (123°F) and lows dropping to around 15°C (60°F).

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

September Precipitation in Holtville

In Holtville in September, the precipitation amount is 9 mm (0.4 in) over the course of 1 day.

September Precipitation Trends in Holtville

The chart displays monthly precipitation patterns in Holtville, 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 Holtville, September typically receives around 9 mm (0.4 inches) of precipitation spread over approximately 1 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 Holtville

In Holtville in September, humidity is 52%. With an average temperature of 32°C (90°F), this humidity feels like a warm, sticky embrace, making outdoor activities a bit challenging for travelers as the heat wraps around them, urging frequent breaks for hydration and shade.

September Average Humidity in Holtville

This chart illustrates the average monthly humidity levels in Holtville, 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 Holtville is approximately 52%, 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 Holtville

In Holtville in September, the maximum UV index reaches 10, which corresponds to a very high Exposure Category. With a time to burn of just 15 minutes, it's crucial to take precautions. For more detailed information, you can check the Hourly UV Index in Holtville.

Maximum UV Index Levels in Holtville for September

The chart shows the monthly maximum UV Index (UVI) for Holtville 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 Holtville typically reaches 10, which falls under the very high exposure category.

Data source: Holtville 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 Holtville Compares to Other Months

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

This table compares monthly weather conditions in Holtville, showing how September’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	15°C (59°F)	10 mm (0.4 inches)	72%	moderate
February Weather	16°C (62°F)	15 mm (0.6 inches)	77%	high
March Weather	20°C (68°F)	10 mm (0.4 inches)	67%	very high
April Weather	24°C (76°F)	4 mm (0.2 inches)	56%	very high
May Weather	27°C (82°F)	1 mm (0.1 inches)	46%	extreme
June Weather	33°C (91°F)	0 mm (0.0 inches)	48%	extreme
July Weather	36°C (98°F)	8 mm (0.3 inches)	46%	extreme
August Weather	36°C (98°F)	6 mm (0.3 inches)	42%	extreme
September Weather	32°C (90°F)	9 mm (0.4 inches)	52%	very high
October Weather	25°C (78°F)	3 mm (0.1 inches)	58%	high
November Weather	19°C (67°F)	4 mm (0.2 inches)	66%	moderate
December Weather	14°C (58°F)	10 mm (0.4 inches)	74%	moderate