Contents
- Weather in May
- Frequently asked questions
- Average temperature in May
- Average pressure in May
- Average wind speed in May
- Average humidity in May
- Average rainfall in May
- Average rainfall days in May
- Average snowfall in May
- Average snowfall days in May
- Average sea temperature in May
- Average daylight in May
- Average sunshine in May
- Average sunshine days in May
- Average UV index in May
- Average cloud cover in May
- Average visibility in May
Weather in May
Temperature
Seattle in May denotes a subtle temperature transition, adjusting from an average high of a moderate 56.5°F (13.6°C) in April to a still refreshing 64.8°F (18.2°C). During May nights, Seattle witnesses a consistent average temperature of 44.8°F (7.1°C).Humidity
The average relative humidity in May is 75%.Rainfall
In Seattle, during May, the rain falls for 7 days and regularly aggregates up to 0.39" (10mm) of precipitation. Throughout the year, there are 84.2 rainfall days, and 5.2" (132mm) of precipitation is accumulated.Snowfall
In Seattle, snow does not fall in April through October and December.Ocean temperature
In Seattle, the average seawater temperature in May is 46.6°F (8.1°C).Note: Unprotected swimming in 46.6°F (8.1°C) is dangerous due to potential cold shock. Especially when temperatures go below 50°F (10°C), leading to hyperventilation.
Daylight
In May, the average length of the day is 15h and 10min.On the first day of May, sunrise is at 5:50 am and sunset at 8:22 pm. On the last day of the month, sunrise is at 5:15 am and sunset at 8:58 pm PDT.
Sunshine
The average sunshine in May is 9.2h.UV index
In Seattle, the average daily maximum UV index in May is 4. A UV Index estimate of 3 to 5 represents a moderate health risk from unprotected exposure to Sun's UV rays for the ordinary person.Note: The average daily UV index of 4 in May transforms into the following instructions:
Put precautions into practice - Protective measures against sun-induced damage are advised. The solar radiation is most powerful near the mid-day, so the exposure to the direct Sun should be reduced accordingly. Stay sun-safe with clothing that is both closely woven and worn loosely.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What are the temperatures in Seattle in May?
What is the average humidity in May?
How much does it rain in May?
When it does not snow?
How cold is the water in May?
How many hours of daylight does Seattle have in May?
When is the sunrise / sunset in May?
How long on average sun shines in May?
What is the UV index intensity in May?
Average temperature in May
Seattle, WA
- Average high temperature in May: 64.8°F
The warmest month (with the highest average high temperature) is August (76.3°F).
The month with the lowest average high temperature is December (43.7°F).
- Average low temperature in May: 44.8°F
The month with the highest average low temperature is August (54°F).
The coldest month (with the lowest average low temperature) is December (35.1°F).
Average pressure in May
Seattle, WA
- Average pressure in May: 30.02"Hg
The month with the highest atmospheric pressure is January (30.1"Hg).
The months with the lowest atmospheric pressure are March, August and September (30.01"Hg).
Average wind speed in May
Seattle, WA
- Average wind speed in May: 4mph
The windiest month (with the highest average wind speed) is March (5.3mph).
The calmest months (with the lowest average wind speed) are July and August (3.5mph).
Average humidity in May
Seattle, WA
- Average humidity in May: 75%
The month with the highest relative humidity is January (85%).
The month with the lowest relative humidity is July (69%).
Average rainfall in May
Seattle, WA
- Average rainfall in May: 0.39"
The wettest month (with the highest rainfall) is December (0.87").
The driest months (with the least rainfall) are July and August (0.12").
Average rainfall days in May
Seattle, WA
- Average rainfall days in May: 7 days
The month with the highest number of rainy days is November (9.1 days).
The month with the least rainy days is August (2.8 days).
Average snowfall in May
Seattle, WA
- Average snowfall in May: 0"
The month with the highest snowfall is February (0.71").
The months with the least snowfall are April, May, June, July, August, September, October and December (0").
Average snowfall days in May
Seattle, WA
- Average snowfall days in May: 0 days
The month with the highest number of snowfall days is February (1.9 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).
Average sea temperature in May
Seattle, WA
- Average sea temperature in May: 46.6°F
The best month for swimming (with the highest average sea temperature) is August (53.5°F).
The coldest month (with the lowest average sea temperature) is February (45.3°F).
Average daylight in May /
Average sunshine in May
Seattle, WA
- Average daylight in May: 15h and 1min
The month with the longest days is June (Average daylight: 15h and 54min).
The month with the shortest days is December (Average daylight: 8h and 30min).
- Average sunshine in May: 9h and 1min
The month with the most sunshine is August (Average sunshine: 10h and 42min).
The month with the least sunshine is December (Average sunshine: 4h and 18min).
Average sunshine days in May
Seattle, WA
- Average sunshine days in May: 20.3 days
The month with the most sunshine days is August (25.9 days).
The month with the least sunshine days is November (16.8 days).
Average UV index in May
Seattle, WA
- Average UV index in May: 4
The month with the highest UV index is July (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 2).
Average cloud cover in May
Seattle, WA
- Average cloud cover in May: 41
The month with the most cloud cover is December (Cloud cover 56).
The month with the least cloud cover is August (Cloud cover 25).
Average visibility in May
Seattle, WA
- Average visibility in May: 6mi
The months with the highest visibility are April, May, June, July, August, September and October (6mi).
The months with the lowest visibility are January, February, March, November and December (5mi).
Seattle, Washington, USA
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