September Weather in Si Ma Cai, Vietnam

Last updated: August 28, 2025

In September, the average temperature in Si Ma Cai, Vietnam hovers around 23°C (74°F), with a comfortable minimum of 14°C (57°F) and a warm maximum of 31°C (88°F). Expect 229 mm (9.0 in) of precipitation spread over 24 days, resulting in an average humidity of 81%. Stay prepared for a mix of warm days and rainy spells!

September Temperature in Si Ma Cai

In September in Si Ma Cai, the average temperature is 23°C (74°F). Maximums can reach 31°C (88°F), while minimums can be as low as 14°C (57°F). This pleasant climate makes Si Ma Cai an ideal destination for travelers looking to enjoy mild and comfortable weather.

September Weather in Si Ma Cai: Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in Si Ma Cai, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Si Ma Cai, September typically has an average temperature of 23°C (74°F), with highs reaching up to 31°C (88°F) and lows dropping to around 14°C (57°F).

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

September Precipitation in Si Ma Cai

In Si Ma Cai in September, the precipitation amount is 229 mm (9.0 in) spread over 24 days.

September Precipitation Trends in Si Ma Cai

The chart displays monthly precipitation patterns in Si Ma Cai, 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 Si Ma Cai, September typically receives around 229 mm (9.0 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 Si Ma Cai

In Si Ma Cai in September, humidity is 81%. With an average temperature of 23°C (74°F), this humidity feels like a warm, heavy blanket draped over your skin, making travel feel a bit more sluggish and requiring plenty of water breaks to stay comfortable.

September Average Humidity in Si Ma Cai

This chart illustrates the average monthly humidity levels in Si Ma Cai, 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 Si Ma Cai is approximately 81%, 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 Si Ma Cai

In Si Ma Cai in September, the maximum UV index reaches 13, which corresponds to an extreme Exposure Category. With a time to burn of just 10 minutes, it's crucial to take protective measures. For detailed information, you can check the Hourly UV Index in Si Ma Cai.

Maximum UV Index Levels in Si Ma Cai for September

The chart shows the monthly maximum UV Index (UVI) for Si Ma Cai 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 Si Ma Cai typically reaches 13, which falls under the extreme exposure category.

Data source: Si Ma Cai 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 Si Ma Cai Compares to Other Months

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

This table compares monthly weather conditions in Si Ma Cai, showing how September’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	13°C (56°F)	42 mm (1.7 inches)	57%	very high
February Weather	14°C (58°F)	28 mm (1.1 inches)	67%	very high
March Weather	18°C (65°F)	41 mm (1.6 inches)	58%	extreme
April Weather	20°C (69°F)	92 mm (3.6 inches)	53%	extreme
May Weather	23°C (74°F)	107 mm (4.2 inches)	69%	extreme
June Weather	25°C (77°F)	182 mm (7.2 inches)	83%	extreme
July Weather	24°C (76°F)	329 mm (12.9 inches)	90%	extreme
August Weather	24°C (76°F)	455 mm (17.9 inches)	90%	extreme
September Weather	23°C (74°F)	229 mm (9.0 inches)	81%	extreme
October Weather	20°C (69°F)	156 mm (6.1 inches)	75%	extreme
November Weather	17°C (63°F)	37 mm (1.5 inches)	74%	very high
December Weather	13°C (56°F)	35 mm (1.4 inches)	69%	very high