October Weather in Portland, United States

Last updated: June 24, 2025

In October, the average temperature in Portland, United States is a mild 14°C (57°F), with temperatures ranging from a brisk -2°C (29°F) to a sweltering 33°C (91°F). Expect about 97 mm (3.8 in) of precipitation spread over 12 days, contributing to an average humidity of 81%. Embrace the diverse weather, as it offers a unique experience every day!

October Temperature in Portland

In October in Portland, the average temperature is 14°C (57°F), with maximums reaching 33°C (91°F) and minimums plummeting to as low as -2°C (29°F). It's advisable to pack layers to accommodate the wide temperature range while enjoying your travels.

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

The chart illustrates October temperature patterns in Portland, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Portland, October typically has an average temperature of 14°C (57°F), with highs reaching up to 33°C (91°F) and lows dropping to around -2°C (29°F).

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

October Precipitation in Portland

In Portland in October, the precipitation amount is 97 mm (3.8 in) spread over 12 days.

October Precipitation Trends in Portland

The chart displays monthly precipitation patterns in Portland, 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 Portland, October typically receives around 97 mm (3.8 inches) of precipitation spread over approximately 12 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 Portland

In Portland in October, humidity is 81%. With an average temperature of 14°C (57°F), this humidity feels like a warm, dense blanket that clings to your skin, making outdoor exploration a bit heavier and more tiring.

October Average Humidity in Portland

This chart illustrates the average monthly humidity levels in Portland, 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 Portland is approximately 81%, 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 Portland

In Portland in October, the maximum UV index is 6, which corresponds to a high Exposure Category. The time to burn is approximately 25 minutes. To find the hourly UV index in Portland, you can refer to this Hourly UV Index in Portland.

Maximum UV Index Levels in Portland for October

The chart shows the monthly maximum UV Index (UVI) for Portland 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 Portland typically reaches 6, which falls under the high exposure category.

Data source: Portland 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 Portland Compares to Other Months

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

This table compares monthly weather conditions in Portland, showing how October’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	-2°C (29°F)	74 mm (2.9 inches)	85%	moderate
February Weather	0°C (32°F)	88 mm (3.4 inches)	85%	moderate
March Weather	5°C (42°F)	101 mm (4.0 inches)	86%	high
April Weather	10°C (51°F)	93 mm (3.7 inches)	87%	very high
May Weather	17°C (63°F)	127 mm (5.0 inches)	81%	very high
June Weather	22°C (73°F)	114 mm (4.5 inches)	82%	extreme
July Weather	24°C (76°F)	101 mm (4.0 inches)	81%	very high
August Weather	23°C (74°F)	102 mm (4.0 inches)	79%	very high
September Weather	20°C (69°F)	75 mm (2.9 inches)	78%	very high
October Weather	14°C (57°F)	97 mm (3.8 inches)	81%	high
November Weather	5°C (42°F)	82 mm (3.2 inches)	89%	moderate
December Weather	2°C (35°F)	67 mm (2.7 inches)	86%	low