March Weather in Portland, United States

Last updated: June 24, 2025

In March, the average temperature in Portland, United States is a brisk 5°C (42°F). Temperatures can range from a minimum of -13°C (8°F) to a pleasant maximum of 24°C (76°F). Be prepared for about 101 mm (4.0 in) of precipitation spread across 12 days, and anticipate high humidity levels at around 86%.

March Temperature in Portland

In March in Portland, the average temperature is 5°C (42°F), with maximums reaching 24°C (76°F) and minimums dropping as low as -13°C (8°F). Be sure to pack layers to accommodate both warm days and chilly nights while exploring.

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

The chart illustrates March 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, March typically has an average temperature of 5°C (42°F), with highs reaching up to 24°C (76°F) and lows dropping to around -13°C (8°F).

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

March Precipitation in Portland

In Portland in March, the precipitation amount is 101 mm (4.0 in) spread over 12 days.

March Precipitation Trends in Portland

The chart displays monthly precipitation patterns in Portland, with values for each month alongside March’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how March’s conditions compare to those of other months. In Portland, March typically receives around 101 mm (4.0 inches) of precipitation spread over approximately 12 days.

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

Choose your preferred precipitation unit

Millimeters (mm) Inches (in)

March Humidity in Portland

In Portland in March, humidity is 86%. With an average temperature of 5°C (42°F), this humidity feels like a damp chill that penetrates your layers, making outdoor activities quite uncomfortable and prompting you to seek warmth indoors more often.

March Average Humidity in Portland

This chart illustrates the average monthly humidity levels in Portland, with March’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In March, average humidity in Portland is approximately 86%, offering insight into how humid the weather typically is during this month.

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

March UV Index in Portland

In Portland in March, 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 March

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

Data source: Portland March 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 March 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 March’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 March’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