May Weather in Unalaska, United States

Last updated: June 24, 2025

In May, the average temperature in Unalaska, United States hovers around 4°C (40°F), with minimums dipping to -1°C (30°F) and maximums reaching 10°C (50°F). Expect 115 mm (4.5 in) of precipitation spread over 22 days, contributing to a high average humidity of 90%. Embrace the chill and prepare for a cozy, wet month!

May Temperature in Unalaska

In May in Unalaska, the average temperature is 4°C (40°F). Maximum can reach 10°C (50°F) and minimum can be as low as -1°C (30°F). Travelers should prepare for cool conditions and layered clothing for this time of year.

May Weather in Unalaska: Daily Temperature Highs, Lows, and Averages

The chart illustrates May temperature patterns in Unalaska, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Unalaska, May typically has an average temperature of 4°C (40°F), with highs reaching up to 10°C (50°F) and lows dropping to around -1°C (30°F).

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

May Precipitation in Unalaska

In Unalaska in May, the precipitation amount is 115 mm (4.5 in) over a span of 22 days.

May Precipitation Trends in Unalaska

The chart displays monthly precipitation patterns in Unalaska, with values for each month alongside May’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how May’s conditions compare to those of other months. In Unalaska, May typically receives around 115 mm (4.5 inches) of precipitation spread over approximately 22 days.

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

Choose your preferred precipitation unit

Millimeters (mm) Inches (in)

May Humidity in Unalaska

In Unalaska in May humidity is 90%. With an average temperature of 4°C (40°F), this humidity feels like a damp chill that penetrates your clothes, making even short excursions outside seem uncomfortable and uninviting.

May Average Humidity in Unalaska

This chart illustrates the average monthly humidity levels in Unalaska, with May’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In May, average humidity in Unalaska is approximately 90%, offering insight into how humid the weather typically is during this month.

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

May UV Index in Unalaska

In Unalaska in May, 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 Unalaska, you can refer to this Hourly UV Index in Unalaska.

Maximum UV Index Levels in Unalaska for May

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

Data source: Unalaska May 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 May Weather in Unalaska Compares to Other Months

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

This table compares monthly weather conditions in Unalaska, showing how May’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	-1°C (30°F)	95 mm (3.8 inches)	83%	low
February Weather	1°C (33°F)	157 mm (6.2 inches)	84%	low
March Weather	0°C (32°F)	92 mm (3.6 inches)	83%	moderate
April Weather	2°C (35°F)	99 mm (3.9 inches)	84%	moderate
May Weather	4°C (40°F)	115 mm (4.5 inches)	90%	high
June Weather	7°C (46°F)	100 mm (3.9 inches)	93%	high
July Weather	10°C (50°F)	65 mm (2.6 inches)	95%	very high
August Weather	11°C (51°F)	89 mm (3.5 inches)	92%	very high
September Weather	9°C (48°F)	117 mm (4.6 inches)	86%	moderate
October Weather	5°C (42°F)	147 mm (5.8 inches)	82%	moderate
November Weather	2°C (37°F)	113 mm (4.5 inches)	81%	low
December Weather	0°C (32°F)	157 mm (6.2 inches)	82%	low