October Weather in Fairfax, United States

Last updated: June 24, 2025

The average temperature in Fairfax, United States during October hovers around 9°C (48°F). However, be prepared for the extremes, as temperatures can dip to a chilling -16°C (3°F) and soar to a warm 30°C (86°F). Expect about 97 mm (3.8 in) of precipitation spread over 10 days, and with an average humidity of 84%, you might want to pack an umbrella along with your lighter layers!

October Temperature in Fairfax

In October in Fairfax, the average temperature is 9°C (48°F), with maximums reaching up to 30°C (86°F) and minimums dropping as low as -16°C (3°F). Travelers should be prepared for a wide range of temperatures during this time.

October Weather in Fairfax: Daily Temperature Highs, Lows, and Averages

The chart illustrates October temperature patterns in Fairfax, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Fairfax, October typically has an average temperature of 9°C (48°F), with highs reaching up to 30°C (86°F) and lows dropping to around -16°C (3°F).

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

October Precipitation in Fairfax

In Fairfax in October, the total precipitation amount is 97 mm (3.8 in) over a span of 10 days.

October Precipitation Trends in Fairfax

The chart displays monthly precipitation patterns in Fairfax, with values for each month alongside October’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how October’s conditions compare to those of other months. In Fairfax, October typically receives around 97 mm (3.8 inches) of precipitation spread over approximately 10 days.

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

Choose your preferred precipitation unit

Millimeters (mm) Inches (in)

October Humidity in Fairfax

In Fairfax in October, humidity is 84%. With an average temperature of 9°C (48°F), this humidity feels like a damp chill that envelops you, making it essential to dress in layers and stay active, as the moisture in the air can quickly lead to discomfort while traveling.

October Average Humidity in Fairfax

This chart illustrates the average monthly humidity levels in Fairfax, with October’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In October, average humidity in Fairfax is approximately 84%, offering insight into how humid the weather typically is during this month.

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

October UV Index in Fairfax

In Fairfax in October, the maximum UV index reaches 5, which corresponds to a moderate Exposure Category. Under these conditions, the estimated time to burn is approximately 30 minutes. For more details, you can check the Hourly UV Index in Fairfax.

Maximum UV Index Levels in Fairfax for October

The chart shows the monthly maximum UV Index (UVI) for Fairfax in October, 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 October, the maximum UV index in Fairfax typically reaches 5, which falls under the moderate exposure category.

Data source: Fairfax October 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 October Weather in Fairfax Compares to Other Months

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

This table compares monthly weather conditions in Fairfax, showing how October’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	-9°C (16°F)	26 mm (1.0 inches)	87%	moderate
February Weather	-9°C (16°F)	27 mm (1.1 inches)	90%	moderate
March Weather	0°C (33°F)	62 mm (2.5 inches)	85%	moderate
April Weather	6°C (43°F)	80 mm (3.1 inches)	84%	very high
May Weather	15°C (60°F)	124 mm (4.9 inches)	78%	very high
June Weather	22°C (72°F)	106 mm (4.2 inches)	80%	very high
July Weather	23°C (74°F)	123 mm (4.8 inches)	81%	very high
August Weather	21°C (71°F)	124 mm (4.9 inches)	81%	very high
September Weather	18°C (65°F)	118 mm (4.6 inches)	81%	very high
October Weather	9°C (48°F)	97 mm (3.8 inches)	84%	moderate
November Weather	1°C (34°F)	30 mm (1.2 inches)	88%	moderate
December Weather	-4°C (24°F)	40 mm (1.6 inches)	84%	low