Monthly weather forecast and climate
Portland, OR

A colorful autumn view of the outline of Portland City, Oregon, USA
A colorful autumn view of the outline of Portland City, Oregon, USA
January, the same as December, in Portland, Oregon, is a frosty winter month, with average temperature ranging between max 46.2°F (7.9°C) and min 35.2°F (1.8°C). In Portland, the average high-temperature is almost the same as in December - a still frosty 46.2°F (7.9°C). Weather in January »

February, the last month of the winter, in Portland, is also a frosty month, with average temperature ranging between max 47.5°F (8.6°C) and min 35.8°F (2.1°C). In Portland, Oregon, the average high-temperature is practically the same as in January - a still chilly 47.5°F (8.6°C). Weather in February »

March, the first month of the spring, in Portland, is a cool month, with average temperature ranging between min 38.1°F (3.4°C) and max 52.5°F (11.4°C). In Portland, the average high-temperature in March is practically the same as in February - a cool 52.5°F (11.4°C). Weather in March »

April in Portland, Oregon, is a moderate spring month, with average temperature varying between 39.7°F (4.3°C) and 58.6°F (14.8°C). In April, the average high-temperature marginally rises, from a fresh 52.5°F (11.4°C) in March, to a mild 58.6°F (14.8°C). Weather in April »

May, the last month of the spring, in Portland, is a comfortable month, with average temperature varying between 67.1°F (19.5°C) and 44.2°F (6.8°C). In May, the average high-temperature marginally rises, from a mild 58.6°F (14.8°C) in April, to a comfortable 67.1°F (19.5°C). Weather in May »

June, the first month of the summer, in Portland, is an agreeable month, with temperature in the range of an average low of 48.4°F (9.1°C) and an average high of 72.1°F (22.3°C). In June, the average high-temperature is almost the same as in May - an agreeable 72.1°F (22.3°C). Weather in June »

July is a moderately hot summer month in Portland, Oregon, with temperature in the range of an average low of 52.5°F (11.4°C) and an average high of 80.6°F (27°C). In Portland, the average high-temperature slightly increases, from a pleasant 72.1°F (22.3°C) in June, to a warm 80.6°F (27°C). Weather in July »

The last month of the summer, August, is also a moderately hot month in Portland, Oregon, with average temperature ranging between min 55°F (12.8°C) and max 81.5°F (27.5°C). The warmest month is August, with an average high-temperature of 81.5°F (27.5°C) and an average low-temperature of 55°F (12.8°C). In August, the average heat index is evaluated at 84.2°F (29°C). Weather in August »

September, the first month of the autumn, in Portland, is still a warm month, with temperature in the range of an average high of 74.1°F (23.4°C) and an average low of 51.3°F (10.7°C). In September, the average high-temperature marginally drops, from a warm 81.5°F (27.5°C) in August, to a still moderately hot 74.1°F (23.4°C). Weather in September »

October, the same as September, is another comfortable autumn month in Portland, Oregon, with temperature in the range of an average high of 61.7°F (16.5°C) and an average low of 45.5°F (7.5°C). In October, the average high-temperature decreases, from a moderately hot 74.1°F (23.4°C) in September, to a comfortable 61.7°F (16.5°C). Weather in October »

November, the last month of the autumn, in Portland, is also a fresh month, with average temperature varying between 51.1°F (10.6°C) and 40.3°F (4.6°C). In November, the average high-temperature decreases, from a comfortable 61.7°F (16.5°C) in October, to a fresh 51.1°F (10.6°C). Weather in November »

December, the first month of the winter, in Portland, is still a chilly month, with average temperature fluctuating between 44.1°F (6.7°C) and 34.7°F (1.5°C). With an average high-temperature of 44.1°F (6.7°C) and an average low-temperature of 34.7°F (1.5°C), December is the coldest month. Weather in December »

What are the most humid months in Portland?

January, February and December, with an average relative humidity of 83%, are most humid months.

How many days does it rain in Portland?

In Portland, during the entire year, the rain falls for 173.1 days and collects up to 31.18" (792mm) of precipitation.

When does it snow in Portland?

Months with snowfall in Portland, Oregon, are January through March, November and December.

How many days does it snow in Portland?

In Portland, Oregon, during the entire year, snow falls for 6.4 days, and aggregates up to 3.94" (100mm) of snow.

What is the month with the least sunshine in Portland?

January has the least sunshine of the year in Portland, with an average of 4.1h of sunshine.

What are the months with the lowest UV index in Portland?

Months with the lowest UV index in Portland, Oregon, are January, February, November and December, with an average maximum UV index of 2.

When does it snow the most in Portland?

March is the month with the most snowfall in Portland. Snow falls for 1.6 days and accumulates 1.5" (38mm) of snow.

When it does not snow in Portland?

April through October are months without snowfall in Portland.

When are the longest days in Portland?

June has the longest days of the year in Portland, with an average of 15.6h of daylight.

What is the driest month in Portland?

The month with the least rainfall is July when the rain falls for 4.9 days and typically collects 0.31" (8mm) of precipitation.

When is the highest UV index in Portland?

The month with the highest UV index in Portland, Oregon, is July, with an average maximum UV index of 6.

What is the warmest month in Portland?

August is the warmest month in Portland, Oregon, with an average high-temperature of 81.5°F (27.5°C) and an average low-temperature of 55°F (12.8°C).

What is the least humid month in Portland?

The least humid month in Portland is August, with an average relative humidity of 63%.

What month has the most sunshine in Portland?

The month with the most sunshine in Portland, Oregon, is August, with an average of 10.9h of sunshine.

What is the coldest month in Portland?

December is the coldest month in Portland, with an average high-temperature of 44.1°F (6.7°C) and an average low-temperature of 34.7°F (1.5°C).

What is the rainiest month in Portland?

The month with the most rainfall in Portland, Oregon, is December when the rain falls for 18.5 days and typically aggregates up to 4.53" (115mm) of precipitation.

What is the month with the shortest days in Portland?

With an average of 8.8h of daylight, December has the shortest days of the year.
Average temperature - Portland, OR
Average pressure - Portland, OR

The month with the highest atmospheric pressure is January (30.12").
The month with the lowest atmospheric pressure is August (30").

Average wind speed - Portland, OR

The windiest month (with the highest average wind speed) is January (5.8mph).
The calmest month (with the lowest average wind speed) is August (3.9mph).

Average humidity - Portland, OR
Average rainfall - Portland, OR

The wettest month (with the highest rainfall) is December (4.53").
The driest month (with the least rainfall) is July (0.31").

Average rainfall days - Portland, OR

The month with the highest number of rainy days is March (20.4 days).
The month with the least rainy days is July (4.9 days).

Average snowfall - Portland, OR

The month with the highest snowfall is March (1.5").
Months with the least snowfall are April, May, June, July, August, September and October (0").

Average snowfall days - Portland, OR

The month with the highest number of snowfall days is February (2.3 days).
Months with the least snowfall days are May, June, July, August, September and October (0 days).

Average daylight / Average sunshine - Portland, OR

The month with the longest days is June (Average daylight: 15.6h).
The month with the shortest days is December (Average daylight: 8.8h).

The month with the most sunshine is August (Average sunshine: 10.9h).
The month with the least sunshine is January (Average sunshine: 4.1h).

Average sunshine days - Portland, OR

Months with the most sunshine days are July and August (23.8 days).
The month with the least sunshine days is March (8.3 days).

Average visibility - Portland, OR

Months with the highest visibility are July, August and September (6mi).
Months with the lowest visibility are January, February, March, April, May, June, October, November and December (5mi).