Average Weather in June in Forest Grove Oregon, United States
Daily high temperatures increase by 7°F, from 70°F to 77°F, rarely falling below 60°F or exceeding 88°F.
Daily low temperatures increase by 3°F, from 49°F to 52°F, rarely falling below 42°F or exceeding 58°F.
For reference, on August 3, the hottest day of the year, temperatures in Forest Grove typically range from 54°F to 82°F, while on December 23, the coldest day of the year, they range from 35°F to 45°F.
Average High and Low Temperature in June
The figure below shows you a compact characterization of the hourly average temperatures for the quarter of the year centered on June. The horizontal axis is the day, the vertical axis is the hour of the day, and the color is the average temperature for that hour and day.
Average Hourly Temperature in June
The month of June in Forest Grove experiences very rapidly decreasing cloud cover, with the percentage of time that the sky is overcast or mostly cloudy decreasing from 52% to 33%.
The clearest day of the month is June 30, with clear, mostly clear, or partly cloudy conditions 67% of the time.
For reference, on January 15, the cloudiest day of the year, the chance of overcast or mostly cloudy conditions is 76%, while on August 3, the clearest day of the year, the chance of clear, mostly clear, or partly cloudy skies is 81%.
Cloud Cover Categories in June
A wet day is one with at least 0.04 inches of liquid or liquid-equivalent precipitation. In Forest Grove, the chance of a wet day over the course of June is very rapidly decreasing, starting the month at 27% and ending it at 13%.
For reference, the year's highest daily chance of a wet day is 57% on November 27, and its lowest chance is 4% on August 3.
Probability of Precipitation in June
To show variation within the month and not just the monthly total, we show the rainfall accumulated over a sliding 31-day period centered around each day.
The average sliding 31-day rainfall during June in Forest Grove is rapidly decreasing, starting the month at 2.0 inches, when it rarely exceeds 3.8 inches or falls below 0.5 inches, and ending the month at 0.9 inches, when it rarely exceeds 1.8 inches or falls below 0.1 inches.
Average Monthly Rainfall in June
Over the course of June in Forest Grove, the length of the day is essentially constant. The shortest day of the month is June 1, with 15 hours, 27 minutes of daylight and the longest day is June 21, with 15 hours, 41 minutes of daylight.
Hours of Daylight and Twilight in June
The earliest sunrise of the month in Forest Grove is 5:23 AM on June 15 and the latest sunrise is 4 minutes later at 5:27 AM on June 30.
The earliest sunset is 8:54 PM on June 1 and the latest sunset is 11 minutes later at 9:05 PM on June 26.
Daylight saving time is observed in Forest Grove during 2018, but it neither starts nor ends during June, so the entire month is in daylight saving time.
For reference, on June 21, the longest day of the year, the Sun rises at 5:23 AM and sets 15 hours, 41 minutes later, at 9:04 PM, while on December 21, the shortest day of the year, it rises at 7:49 AM and sets 8 hours, 42 minutes later, at 4:31 PM.
Sunrise & Sunset with Twilight in June
We base the humidity comfort level on the dew point, as it determines whether perspiration will evaporate from the skin, thereby cooling the body. Lower dew points feel drier and higher dew points feel more humid. Unlike temperature, which typically varies significantly between night and day, dew point tends to change more slowly, so while the temperature may drop at night, a muggy day is typically followed by a muggy night.
The chance that a given day will be muggy in Forest Grove is essentially constant during June, remaining around 0% throughout.
For reference, on August 6, the muggiest day of the year, there are muggy conditions 1% of the time, while on November 7, the least muggy day of the year, there are muggy conditions 0% of the time.
Humidity Comfort Levels in June
This section discusses the wide-area hourly average wind vector (speed and direction) at 10 meters above the ground. The wind experienced at any given location is highly dependent on local topography and other factors, and instantaneous wind speed and direction vary more widely than hourly averages.
The average hourly wind speed in Forest Grove is essentially constant during June, remaining around 4.4 miles per hour throughout.
For reference, on December 3, the windiest day of the year, the daily average wind speed is 5.8 miles per hour, while on August 24, the calmest day of the year, the daily average wind speed is 4.4 miles per hour.
Average Wind Speed in June
Wind Direction in June
Forest Grove is located near a large body of water (e.g., ocean, sea, or large lake). This section reports on the wide-area average surface temperature of that water.
The average surface water temperature in Forest Grove is gradually increasing during June, rising by 3°F, from 55°F to 58°F, over the course of the month.
Average Water Temperature in June
Definitions of the growing season vary throughout the world, but for the purposes of this report, we define it as the longest continuous period of non-freezing temperatures (≥ 32°F) in the year (the calendar year in the Northern Hemisphere, or from July 1 until June 30 in the Southern Hemisphere).
The growing season in Forest Grove typically lasts for 6.8 months (208 days), from around April 7 to around October 31, rarely starting before March 4 or after May 6, and rarely ending before October 10 or after November 26.
The month of June in Forest Grove is reliably fully within the growing season.
Time Spent in Various Temperature Bands and the Growing Season in June
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. In this report, we use a base of 50°F and a cap of 86°F.
The average accumulated growing degree days in Forest Grove are increasing during June, increasing by 315°F, from 389°F to 704°F, over the course of the month.
Growing Degree Days in June
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 in Forest Grove is gradually increasing during June, rising by 0.9 kWh, from 6.1 kWh to 7.0 kWh, over the course of the month.
Average Daily Incident Shortwave Solar Energy in June
For the purposes of this report, the geographical coordinates of Forest Grove are 45.520 deg latitude, -123.111 deg longitude, and 187 ft elevation.
The topography within 2 miles of Forest Grove contains only modest variations in elevation, with a maximum elevation change of 262 feet and an average elevation above sea level of 185 feet. Within 10 miles contains only modest variations in elevation (2,228 feet). Within 50 miles contains large variations in elevation (4,337 feet).
The area within 2 miles of Forest Grove is covered by cropland (60%) and artificial surfaces (40%), within 10 miles by cropland (53%) and trees (29%), and within 50 miles by trees (42%) and cropland (22%).
This report illustrates the typical weather in Forest Grove year round, based on a statistical analysis of historical hourly weather reports and model reconstructions from January 1, 1980 to December 31, 2016.
Temperature and Dew Point
There are 4 weather stations near enough to contribute to our estimation of the temperature and dew point in Forest Grove.
For each station, the records are corrected for the elevation difference between that station and Forest Grove 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 Forest Grove is computed as the weighted average of the individual contributions from each station, with weights proportional to the inverse of the distance between Forest Grove and a given station.
The stations contributing to this reconstruction are: Portland-Hillsboro Airport (73%, 13 kilometers, east); Mc Minnville Municipal Airport (15%, 36 kilometers, south); Tillamook Airport (8%, 56 kilometers, west); and Clatsop County Airport (3.7%, 93 kilometers, northwest).
All data relating to the Sun's position (e.g., sunrise and sunset) are computed using astronomical formulas from the book, Astronomical Tables of the Sun, Moon and Planets , by Jean Meeus.
All other weather data, including cloud cover, precipitation, wind speed and direction, and solar flux, come from NASA's MERRA-2 Modern-Era Retrospective Analysis . 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 50-kilometer grid.
Land Use data comes from the Global Land Cover SHARE database , published by the Food and Agriculture Organization of the United Nations.
Elevation data comes from the Shuttle Radar Topography Mission (SRTM) , published by NASA's Jet Propulsion Laboratory.
Names, locations, and time zones of places and some airports come from the GeoNames Geographical Database .
Time zones for aiports and weather stations are provided by AskGeo.com .
Maps are © Esri, with data from National Geographic, Esri, DeLorme, NAVTEQ, UNEP-WCMC, USGS, NASA, ESA, METI, NRCAN, GEBCO, NOAA, and iPC.
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.