Monthly Weather in Seattle, United States
What is the average monthly temperature in Seattle?
The average monthly temperature in Seattle, Washington, United States ranges from 5°C (41.1°F) in February to 20.8°C (69.4°F) in August. Seattle temperature by month is given in the table below.
| Month | Celsius | Fahrenheit |
|---|---|---|
| January | 6.3°C | 43.3°F |
| February | 5.0°C | 41.0°F |
| March | 6.9°C | 44.4°F |
| April | 9.3°C | 48.7°F |
| May | 16.0°C | 60.8°F |
| June | 16.6°C | 61.9°F |
| July | 20.1°C | 68.2°F |
| August | 20.8°C | 69.4°F |
| September | 16.2°C | 61.2°F |
| October | 11.8°C | 53.2°F |
| November | 6.9°C | 44.4°F |
| December | 7.3°C | 45.1°F |
What is the hottest month in Seattle?
The hottest months in Seattle are August, July and June. During August the average temperature outside is 20.8°C (69.4°F), in July it is 20.1°C (68.2°F) and during June the air temperature is around 16.6°C (61.9°F).
What is the coldest month in Seattle?
The coldest months in Seattle are February, January and March. In February the average air temperature drops to 5°C (41°F), in January air temperature is 6.3°C (43.3°F) and during March it is 6.9°C (44.4°F).
How much does it rain on average in Seattle?
On average it rains for 12 month(s) in Seattle, United States with an average of 13.1 days of rain per month. In total Seattle has 157 rainy days in a year.
When does it rain the most in Seattle?
In Seattle it rains the most during the following months.
- December - on average 3.43mm (0.14 inches) of rainfall per day.
- November - on average 2.75mm (0.11 inches) of rainfall per day.
- September - on average 2.38mm (0.09 inches) of rainfall per day.
- April - on average 1.76mm (0.07 inches) of rainfall per day.
- October - on average 1.66mm (0.07 inches) of rainfall per day.
- January - on average 1.4mm (0.06 inches) of rainfall per day.
Does it snow in Seattle?
Yes, it snows in Seattle. The following months have the most amount of snow.
- February. Seattle has 0.09mm (0 inches) of snowfall and 0.04 mm (0 inches) of snow on the ground in February.
- January. Seattle has 0.03mm (0 inches) of snowfall and 0 mm (0 inches) of snow on the ground in January.
When is it windy in Seattle?
The windiest months in Seattle, United States are February, March and April. In February the average windspeed is 21.2 km/h (13.2 mph), during March the windspeed is 19.3 km/h (12 mph) and in April the windspeed is 18.3 km/h (11.4 mph).
What are the least windy months in Seattle?
The least windy months in Seattle are October, November and September. In October the average windspeed is 13.8 km/h (8.6 mph), during November the windspeed is 14.6 km/h (9.1 mph) and in September the windspeed is 15.2 km/h (9.4 mph).
When is it cloudy in Seattle?
The cloudiest months in Seattle, United States are January, December and April. On average in January 77.2% of sky is covered by clouds, in December 73.8% is covered by clouds and in April clouds cover about 71.3% of sky.
When does Seattle have the clearest sky?
Seattle has the clearest sky in July, August and June. In July 24.5% of sky is covered by clouds, in August clouds cover around 36.8% and during June clouds cover about 43.9% of sky.
What is the average daylight duration in Seattle?
The average daylight duration in Seattle is 12 hours 14 minutes 8 seconds.
Which months have the most daylight in Seattle?
The longest days in Seattle are during June, July and May.
- June - 15 hours 54 minutes 54 seconds of daylight.
- July - 15 hours 31 minutes 37 seconds of daylight.
- May - 15 hours 8 minutes 45 seconds of daylight.
Which months have the least daylight in Seattle?
The shortest days in Seattle are during December, January and November.
- December - 8 hours 30 minutes 9 seconds of daylight.
- January - 8 hours 56 minutes 40 seconds of daylight.
- November - 9 hours 18 minutes 49 seconds of daylight.
What are the humidity levels in Seattle throughout the year?
Humidity levels in Seattle, United States range from 58.7% in July to 85.2% in December.
What are the pressure levels in Seattle throughout the year?
Pressure levels in Seattle change from 1013.3 mb (millibars) in March to 1019.1 mb in November.
What is the visibility in Seattle throughout the year?
Visibility in Seattle changes from lowest 12.5 km (7.8 miles) in December to highest 15.8 km (9.8 miles) in July.
What are the UV levels in Seattle throughout the year?
UV levels change in Seattle from 1.8 in December to 8.8 in July.
Which months have the highest UV levels in Seattle throughout the year?
In Seattle, United States the highest UV index is during July, May and June. During July the average UV index is 8.8, in May UV level is 7.8 and in June UV index is around 7.5.
Which months have the lowest UV levels in Seattle throughout the year?
The lowest UV levels in Seattle are in December, January and November. In December the average UV index is around 1.8, in January UV index is 2 and during November UV level is 3.2.