The best times to visit Portland for ideal weather are
May 21st to November 4th
based on average temperature and humidity from NOAA (the National Oceanic and Atmospheric Administration). Read below for more weather and travel details.
Portland Travel Guide
Other Portland Travel Info
Weather in Portland
Average temperatures in Portland vary somewhat. Considering humidity, temperatures feel cold for about half of the year and otherwise nice with a chance of rain or snow throughout most of the year. The area is less temperate than some — in the 35th percentile for pleasant weather — compared to tourist destinations worldwide. Weeks with ideal weather are listed above. If you’re looking for the very warmest time to visit Portland, the hottest months are August, July, and then September. See average monthly temperatures below. The warmest time of year is generally late July where highs are regularly around 67°F (19.4°C) with temperatures rarely dropping below 58.4°F (14.7°C) at night.
Portland Temperatures (Fahrenheit)
Portland Temperatures (Celsius)
The way we experience weather isn’t all about temperature. Higher temperatures affect us much more at higher humidity, and colder temperatures feel piercing with high winds. Our perceived temperatures factor in humidity and wind chill to better represent how hot or cold the day feels to a person.
Portland Perceived Temperature (F)
Portland Perceived Temperature (C)
Average Portland Temperatures by Month
Daily highs (averaged for the month) usually give the best indication of the weather. A significantly lower mean and low generally just means it gets colder at night.
|Month||Avg. High (°F)||Avg. Mean (°F)||Avg. Low (°F)|
|Month||Avg. High (°C)||Avg. Mean (°C)||Avg. Low (°C)|
Precipitation (Rain or Snow)
If dry weather is what you’re after, the months with the lowest chance of significant precipitation in Portland are September, April, and then July. Note that we define “significant precipitation” as .1 inches or more in this section. The lowest chance of rain or snow occurs around mid April. For example, on the week of April 16th there are no days of precipitation on average. By contrast, it’s most likely to rain or snow in mid January with an average of 3 days of significant precipitation the week of January 15th.
When can you find snow in Portland? Weather stations report no annual snow. Please note that a value of 0 for snow in the graph below may either mean there was no snow, or that snow is unreported.
Chance of Precipitation
The graph below shows the % chance of rainy and snowy days in Portland.
Snow on the Ground
The graph below shows the average snow on the ground in Portland (in).
Average Rain and Snow by Month
|Month||Daily Chance of Rain||Average Snow Depth (in)||Total Precipitation (in)|
|Month||Daily Chance of Rain||Average Snow Depth (cm)||Total Precipitation (cm)|
Humidity and Wind
Portland has some extremely humid months, and high humidity throughout the year. The least humid month is September (77.3% relative humidity), and the most humid month is July (81.8%).
Wind in Portland is usually stronger than many places. The windiest month is December, followed by January and November. December’s average wind speed of around 17.6 knots (20.2 MPH or 32.5 KPH) is considered “a fresh breeze.” Maximum sustained winds (the highest speed for the day lasting more than a few moments) are at their highest in early December where average top sustained speeds reach 26 knots, which is considered a strong breeze.
Relative Humidity (%)
The graph below shows the average % humidity by month in Portland.
The graph below shows wind speed (max and average) in knots.
Average Wind Speeds
Show Wind Speeds
All wind speeds are in knots. 1 knot = 1.15 MPH or 1.85 KPH.
|Month||Avg. Wind||Avg. Wind Feel||Sustained High Wind||High Wind Feel|
|Jan||17.1||Strong breeze||24.1||Very strong breeze|
|Feb||14.9||Significant breeze||21.6||Strong breeze|
|Mar||13.8||Significant breeze||20||Very strong breeze|
|Apr||11.8||Significant breeze||17.8||Strong breeze|
|May||12.7||Significant breeze||18.5||Very strong breeze|
|Jun||11.6||Significant breeze||17.4||Strong breeze|
|Jul||12.1||Significant breeze||17.7||Very strong breeze|
|Aug||12.5||Significant breeze||17.9||Strong breeze|
|Sep||13.4||Significant breeze||18.7||Very strong breeze|
|Oct||14.7||Significant breeze||21.1||Strong breeze|
|Nov||16.8||Significant breeze||23.8||Very strong breeze|
|Dec||17.6||Strong breeze||24.7||Very strong breeze|
Show Relative Humidity by Month
|Month||Avg. Relative Humidity|
Is it Safe to Travel to Portland?
Our best data indicates this area is somewhat safe. As of Oct 07, 2019 there are travel warnings for the United Kingdom; exercise a high degree of caution. Check this page for any recent changes or regions to avoid: Travel Advice and Advisories. This advisory was last updated on Sep 06, 2019.
The Busiest and Least Crowded Months
The busiest month for tourism in Portland, the United Kingdom is August, followed by July and May. Prices for hotels and flights will be most expensive during these months, though you can save if you purchase well in advance. Tourists are unlikely to visit Portland in December. Those willing to visit at these times will likely find it the least expensive month.
Estimated Tourism by Month
Most Popular Months to Visit
Overall Portland Travel Experience by Season
Spring (March through May)
Humidity and temperatures combine to make this season feel moderately cold. Highs range from 60.8°F (16°C) and 47.9°F (8.8°C) with warmer temperatures in the later months. Rain is somewhat common with 5 to 6 days of significant precipitation per month. Spring is the second busiest for tourism, which makes it a good time for those looking for things to do.
Summer (June through August)
The middle-year months have comfortably cool weather with high temperatures that are comfortable. These months see moderate precipitation with 5 to 6 days of precipitation per month. June – August is the busiest season for tourism in Portland, so lodging and other accommodations may cost more than usual.
Fall (September through November)
Fall daily highs range from 65.2°F (18.4°C) and 49.5°F (9.7°C), which will feel comfortable given the humidity and wind. It rains or snows a significant amount: 3 to 11 days per month. Tourism is fairly slow during these months due to the weather, so hotels may be lower priced.
Winter (December through February)
Weather is too cold this time of year in Portland to be enjoyable for warm weather travelers. The average high during this season is between 50.3°F (10.2°C) and 45.2°F (7.3°C). On average, it rains or snows a fair amount: 7 to 10 times per month. These times of year are the slowest with tourists.
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