March Weather in Southwest Harbor, United States

Last updated: June 24, 2025

In March, the average temperature in Southwest Harbor, United States hovers around 1°C (34°F). Expect chilly days where temperatures can dip to a brisk -14°C (7°F) and potentially rise to a mild 9°C (49°F). With 83 mm (3.3 in) of precipitation spread over 10 days, you'll want to prepare for the wet weather. The air is notably humid, with an average humidity level of 85%, adding to the season's crispness.

March Temperature in Southwest Harbor

In March in Southwest Harbor, the average temperature is 1°C (34°F). The maximum can reach 9°C (49°F), and the minimum can be as low as -14°C (7°F). Travelers should be prepared for a wide range of temperatures and dress accordingly.

March Weather in Southwest Harbor: Daily Temperature Highs, Lows, and Averages

The chart illustrates March temperature patterns in Southwest Harbor, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Southwest Harbor, March typically has an average temperature of 1°C (34°F), with highs reaching up to 9°C (49°F) and lows dropping to around -14°C (7°F).

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

March Precipitation in Southwest Harbor

In Southwest Harbor in March, the total precipitation amount is 83 mm (3.3 in) over a span of 10 days.

March Precipitation Trends in Southwest Harbor

The chart displays monthly precipitation patterns in Southwest Harbor, 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 Southwest Harbor, March typically receives around 83 mm (3.3 inches) of precipitation spread over approximately 10 days.

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

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Millimeters (mm) Inches (in)

March Humidity in Southwest Harbor

In Southwest Harbor in March, humidity is 85%. With an average temperature of 1°C (34°F), this humidity feels like a biting chill that seeps into your bones, making outdoor travel uncomfortable and urging you to seek warmth indoors rather than explore the surroundings.

March Average Humidity in Southwest Harbor

This chart illustrates the average monthly humidity levels in Southwest Harbor, 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 Southwest Harbor 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 Southwest Harbor

In Southwest Harbor 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 Southwest Harbor.

Maximum UV Index Levels in Southwest Harbor for March

The chart shows the monthly maximum UV Index (UVI) for Southwest Harbor 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 Southwest Harbor typically reaches 5, which falls under the moderate exposure category.

Data source: Southwest Harbor 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 Southwest Harbor Compares to Other Months

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

This table compares monthly weather conditions in Southwest Harbor, showing how March’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	-1°C (30°F)	113 mm (4.4 inches)	88%	low
February Weather	-1°C (31°F)	107 mm (4.2 inches)	88%	moderate
March Weather	1°C (34°F)	83 mm (3.3 inches)	85%	moderate
April Weather	5°C (41°F)	143 mm (5.6 inches)	81%	high
May Weather	8°C (48°F)	105 mm (4.1 inches)	76%	very high
June Weather	12°C (54°F)	95 mm (3.7 inches)	74%	very high
July Weather	15°C (59°F)	82 mm (3.2 inches)	74%	very high
August Weather	16°C (62°F)	87 mm (3.4 inches)	74%	very high
September Weather	15°C (59°F)	105 mm (4.2 inches)	77%	high
October Weather	12°C (54°F)	119 mm (4.7 inches)	82%	moderate
November Weather	6°C (44°F)	139 mm (5.5 inches)	85%	moderate
December Weather	1°C (35°F)	154 mm (6.1 inches)	84%	low