What is the average yearly rainfall in portland or

This section reports on the wide-area average surface temperature of that water. The average water temperature experiences some seasonal variation over the course of the year. The time of year with warmer water lasts for 3. The time of year with cooler water lasts for 4. To characterize how pleasant the weather is in Portland throughout the year, we compute two travel scores. Based on this score, the best time of year to visit Portland for general outdoor tourist activities is from early July to late August , with a peak score in the first week of August.

Based on this score, the best time of year to visit Portland for hot-weather activities is from mid July to mid August , with a peak score in the first week of August. For each hour between AM and PM of each day in the analysis period to , independent scores are computed for perceived temperature, cloud cover, and total precipitation.

Those scores are combined into a single hourly composite score, which is then aggregated into days, averaged over all the years in the analysis period, and smoothed. Our cloud cover score is 10 for fully clear skies, falling linearly to 9 for mostly clear skies, and to 1 for fully overcast skies. Our precipitation score , which is based on the three-hour precipitation centered on the hour in question, is 10 for no precipitation, falling linearly to 9 for trace precipitation, and to 0 for 0.

The growing season in Portland typically lasts for 8. Growing degree days are a measure of yearly heat accumulation used to predict plant and animal development, and defined as the integral of warmth above a base temperature, discarding any excess above a maximum temperature.

Based on growing degree days alone, the first spring blooms in Portland should appear around April 5 , only rarely appearing before March 20 or after April This section discusses the total daily incident shortwave solar energy reaching the surface of the ground over a wide area, taking full account of seasonal variations in the length of the day, the elevation of the Sun above the horizon, and absorption by clouds and other atmospheric constituents.

Shortwave radiation includes visible light and ultraviolet radiation. The average daily incident shortwave solar energy experiences extreme seasonal variation over the course of the year. The brighter period of the year lasts for 2. The brightest month of the year in Portland is July , with an average of 7.

The darker period of the year lasts for 3. The darkest month of the year in Portland is December , with an average of 1. For the purposes of this report, the geographical coordinates of Portland are The topography within 2 miles of Portland contains very significant variations in elevation, with a maximum elevation change of feet and an average elevation above sea level of feet.

Within 10 miles also contains very significant variations in elevation 1, feet. Within 50 miles contains very significant variations in elevation 11, feet. This report illustrates the typical weather in Portland, based on a statistical analysis of historical hourly weather reports and model reconstructions from January 1, to December 31, There are 3 weather stations near enough to contribute to our estimation of the temperature and dew point in Portland.

For each station, the records are corrected for the elevation difference between that station and Portland according to the International Standard Atmosphere , and by the relative change present in the MERRA-2 satellite-era reanalysis between the two locations.

The estimated value at Portland is computed as the weighted average of the individual contributions from each station, with weights proportional to the inverse of the distance between Portland and a given station. To get a sense of how much these sources agree with each other, you can view a comparison of Portland and the stations that contribute to our estimates of its temperature history and climate.

Please note that each source's contribution is adjusted for elevation and the relative change present in the MERRA-2 data. All data relating to the Sun's position e. This reanalysis combines a variety of wide-area measurements in a state-of-the-art global meteorological model to reconstruct the hourly history of weather throughout the world on a kilometer grid.

Names, locations, and time zones of places and some airports come from the GeoNames Geographical Database. Time zones for airports and weather stations are provided by AskGeo. The information on this site is provided as is, without any assurances as to its accuracy or suitability for any purpose.

Weather data is prone to errors, outages, and other defects. We assume no responsibility for any decisions made on the basis of the content presented on this site.

We draw particular cautious attention to our reliance on the MERRA-2 model-based reconstructions for a number of important data series. While having the tremendous advantages of temporal and spatial completeness, these reconstructions: 1 are based on computer models that may have model-based errors, 2 are coarsely sampled on a 50 km grid and are therefore unable to reconstruct the local variations of many microclimates, and 3 have particular difficulty with the weather in some coastal areas, especially small islands.

We further caution that our travel scores are only as good as the data that underpin them, that weather conditions at any given location and time are unpredictable and variable, and that the definition of the scores reflects a particular set of preferences that may not agree with those of any particular reader. Please review our full terms contained on our Terms of Service page.

You're permitted to use this graph as long as you provide prominent attribution with a link back close to the use of the graph. For print usage, please acquire a license. Full Year. Spring Summer Fall Winter. Climate in Portland Link. History: Weather in June ». July in Portland , Oregon , is a warm summer month, with average temperature ranging between min In Portland, the average high-temperature in July slightly increases, from an agreeable Weather in July ». August is the warmest month, with an average high-temperature of In August, the average heat index is appraised at Weather in August ».

September , the first month of the autumn, in Portland , is also a moderately hot month, with average temperature varying between In Portland, Oregon , the average high-temperature in September marginally drops, from Weather in September ». October , like September , in Portland , Oregon , is another enjoyable autumn month, with temperature in the range of an average low of In Portland, the average high-temperature drops, from a moderately hot Weather in October ».

November , the last month of the autumn, in Portland , is also a fresh month, with average temperature varying between In November, the average high-temperature decreases, from a comfortable Weather in November ».

The first month of the winter, December , is still a chilly month in Portland , Oregon , with average temperature varying between The coldest month is December, with an average high-temperature of Weather in December ».

FAQ What is the most humid month in Portland? How much does it rain in Portland? Throughout the year, there are When does it snow in Portland? January through March , November and December are months with snowfall.

How much does it snow in Portland? Throughout the year, in Portland, Oregon, there are 6. What is the month with the least sunshine in Portland? With an average of 4. What is the month with the lowest UV index in Portland? When does it snow the most in Portland? March is the month with the most snowfall in Portland, Oregon. Snow falls for 1. When it does not snow in Portland? April through October are months without snowfall. When are the longest days in Portland?

The month with the longest days in Portland, Oregon, is June , with an average of What is the driest month in Portland? July is the month with the least rainfall in Portland, Oregon. Rain falls for 4. What is the month with the highest UV index in Portland? What is the warmest month in Portland? The warmest month in Portland, Oregon, is August , with an average high-temperature of What is the least humid month in Portland? Start Your Review of Portland. Members receive 10 FREE city profile downloads a month, unlimited access to our detailed cost of living calculator and analysis, unlimited access to our DataEngine, and more.

Enhanced Cost of Living Calculator Now includes childcare, taxes, health, housing for home owners vs renters, insurance costs and more when you upgrade to premium. Log In Sign Up. Climate in Portland, Oregon. Snowfall 2. Precipitation July High Low Annual Rainfall US Avg: Annual Snowfall US Avg: 25". Precipitation Days US Avg: Sunny Days US Avg: Select Map Options. Reviews for Portland Reviews.