The best times to travel section shows how the months compare for a visit, so you can find the time of year that fits what you want to do.
Background colours of the months:
The colour shows the typical temperature: yellow (hot), green (mild) and blue (cold). How strong the colour is shows the travel season: full colour means high season, soft colour means shoulder season and soft-striped means off season.
Weather symbols:
Each month has one symbol showing what the weather is typically like, such as hot and sunny, freezing or a rainy or snowy season. Use them to quickly spot months that match the weather you want, or to avoid the ones that don't.
Crowdedness:
The people icon shows how busy the place usually is. The more people, the more crowded it gets.
Additional notes:
The grey info boxes point out special things worth knowing, like recurring weather issues or seasonal events.
| Average climate data for Portland, United States | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Month | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Year |
| Average maximum temperature (°C) | -1 | 0 | 4 | 9 | 14 | 18 | 23 | 22 | 19 | 13 | 8 | 2 | 23 |
| Average minimum temperature (°C) | -6 | -6 | -2 | 3 | 8 | 13 | 17 | 16 | 14 | 8 | 3 | -2 | -6 |
| Average precipitation (mm) | 34 | 39 | 44 | 52 | 47 | 54 | 47 | 56 | 30 | 60 | 44 | 51 | 560 |
| Average rainfall days (days) | 6 | 6 | 9 | 13 | 13 | 13 | 15 | 13 | 10 | 11 | 9 | 8 | 127 |
| Average snowfall (mm) | 70 | 74 | 54 | 17 | 0 | 0 | 0 | 0 | 0 | 1 | 24 | 58 | 299 |
| Average snowfall days (days) | 8 | 7 | 6 | 2 | 0 | 0 | 0 | 0 | 0 | 0 | 2 | 5 | 30 |
| Average relative humidity (%) | 79 | 78 | 77 | 78 | 81 | 83 | 83 | 79 | 78 | 78 | 75 | 78 | 79 |
| Average wind speed (km/h) | 20 | 19 | 19 | 17 | 15 | 14 | 12 | 12 | 14 | 17 | 18 | 18 | 16 |
| Average water temperature (°C) | 5 | 4 | 3 | 5 | 8 | 13 | 16 | 18 | 16 | 13 | 10 | 7 | 10 |
| Average daily daylight hours (h) | 9 | 10 | 12 | 13 | 14 | 15 | 15 | 13 | 12 | 11 | 9 | 9 | 12 |
| Average daily sunshine hours (h) | 5 | 4 | 5 | 8 | 8 | 9 | 10 | 10 | 8 | 6 | 5 | 4 | 7 |
| Average cloud coverage (%) | 46 | 48 | 50 | 48 | 44 | 38 | 32 | 29 | 32 | 42 | 41 | 49 | 42 |
| Average UV index | 2 | 2 | 2 | 3 | 4 | 5 | 5 | 5 | 4 | 3 | 2 | 2 | 3 |
The warmest month, with the highest average maximum temperature, is July (22.5 °C). The month with the lowest average maximum temperature is January (-0.6 °C). Overall, the average maximum temperature over the whole year is 11 °C.
The month with the highest average minimum temperature is July (16.7 °C). The coldest month, with the lowest average minimum temperature, is January (-6.2 °C). Overall, the average minimum temperature over the whole year is 5.5 °C.
The month with the highest average water temperature is August (17.7 °C). The month with the lowest average water temperature is March (3.4 °C). Overall, the average water temperature over the whole year is 9.8 °C.
The wettest month, with the highest amount of precipitation, is October (60.5 mm). The driest month, with the least amount of precipitation, is September (30.4 mm). Over the whole year there are 559.8 mm of rainfall on average.
The month with the most days of rain is July (14.8 days). The month with the fewest days of rain is January (5.6 days). Over the whole year there are 126.6 days of rain on average.
The month with the most snowfall is February (74 mm). The months with the least snowfall are May, June, July, August and September (0 mm). Over the whole year there are 298.5 mm of snowfall on average.
The month with the most days of snowfall is January (7.8 days). The months with the fewest days of snowfall are June and September (0 days). Over the whole year there are 29.9 days of snowfall on average.
The month with the highest average relative humidity is July (82.9 %). The month with the lowest average relative humidity is November (74.9 %). The overall average relative humidity over the whole year is 79 %.
The windiest month, with the highest average wind speed, is January (20.3 km/h). The calmest month, with the lowest average wind speed, is August (12 km/h). The overall average wind speed over the whole year is 16.2 km/h.
The month with the cloudiest skies, so the highest cloud coverage, is March (49.8 %). The month with the clearest skies, so the lowest cloud coverage, is August (29.1 %). Over the whole year there is an average cloud coverage of 41.5 %.
The month with the longest days, so the most daylight, is June (Average daylight: 15 h). The month with the shortest days, so the least daylight, is December (Average daylight: 9 h). Over the whole year there are 11.9 h of daylight per day on average.
The month with the most sunshine per day is July (Average sunshine: 10 h). The month with the least sunshine per day is December (Average sunshine: 4 h). Over the whole year there are 6.9 h of sunlight per day on average.
The months with the highest average UV index are June, July and August (UV index: 5). The months with the lowest average UV index are January, February, March, November and December (UV index: 2). Over the whole year the average UV index is 3.2.
