March Weather in Portland, United States

Last updated: June 24, 2025

In Portland, United States, the average temperature in March hovers around -3°C (27°F). However, temperatures can vary significantly, with minimums plummeting to -27°C (-16°F) and highs reaching 22°C (72°F). During this month, you can expect about 27 mm (1.1 in) of precipitation spread over 5 days, coupled with an average humidity level of 85%.

March Temperature in Portland

In March in Portland, the average temperature is -3°C (27°F), with maximums reaching up to 22°C (72°F) and minimums dropping as low as -27°C (-16°F). It’s advisable for travelers to prepare for a wide range of temperatures and dress in layers to stay comfortable.

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 -3°C (27°F), with highs reaching up to 22°C (72°F) and lows dropping to around -27°C (-16°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 27 mm (1.1 in) over a period of 5 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 27 mm (1.1 inches) of precipitation spread over approximately 5 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 85%. With an average temperature of -3°C (27°F), this humidity feels like a biting chill that seeps through layers of clothing, making travel seem daunting and the cold air sting your skin.

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 85%, 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 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 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 5, which falls under the moderate 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	-12°C (10°F)	18 mm (0.7 inches)	90%	low
February Weather	-13°C (9°F)	19 mm (0.8 inches)	92%	moderate
March Weather	-3°C (27°F)	27 mm (1.1 inches)	85%	moderate
April Weather	4°C (39°F)	41 mm (1.6 inches)	81%	high
May Weather	13°C (56°F)	55 mm (2.2 inches)	75%	very high
June Weather	20°C (69°F)	91 mm (3.6 inches)	79%	very high
July Weather	22°C (72°F)	62 mm (2.4 inches)	76%	very high
August Weather	20°C (68°F)	81 mm (3.2 inches)	78%	very high
September Weather	15°C (60°F)	68 mm (2.7 inches)	77%	high
October Weather	6°C (44°F)	79 mm (3.1 inches)	79%	moderate
November Weather	-2°C (28°F)	21 mm (0.8 inches)	86%	moderate
December Weather	-8°C (18°F)	39 mm (1.5 inches)	86%	low