Average Weather in John Day Oregon, United States
In John Day, the summers are short, hot, dry, and mostly clear and the winters are very cold and partly cloudy. Over the course of the year, the temperature typically varies from 27°F to 89°F and is rarely below 11°F or above 97°F.
Based on the tourism score, the best time of year to visit John Day for warm-weather activities is from early July to late August.
The hot season lasts for 2.7 months, from June 22 to September 13, with an average daily high temperature above 79°F. The hottest day of the year is August 3, with an average high of 89°F and low of 57°F.
The cold season lasts for 3.5 months, from November 13 to February 28, with an average daily high temperature below 49°F. The coldest day of the year is December 20, with an average low of 27°F and high of 40°F.
Average High and Low Temperature
The figure below shows you a compact characterization of the entire year of hourly average temperatures. The horizontal axis is the day of the year, 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 John Day, the average percentage of the sky covered by clouds experiences significant seasonal variation over the course of the year.
The clearer part of the year in John Day begins around June 14 and lasts for 3.8 months, ending around October 6. On July 29, the clearest day of the year, the sky is clear, mostly clear, or partly cloudy 83% of the time, and overcast or mostly cloudy 17% of the time.
The cloudier part of the year begins around October 6 and lasts for 8.2 months, ending around June 14. On January 16, the cloudiest day of the year, the sky is overcast or mostly cloudy 67% of the time, and clear, mostly clear, or partly cloudy 33% of the time.
Cloud Cover Categories
A wet day is one with at least 0.04 inches of liquid or liquid-equivalent precipitation. The chance of wet days in John Day varies throughout the year.
The wetter season lasts 7.8 months, from October 23 to June 17, with a greater than 17% chance of a given day being a wet day. The chance of a wet day peaks at 28% on December 16.
The drier season lasts 4.2 months, from June 17 to October 23. The smallest chance of a wet day is 6% on August 15.
Among wet days, we distinguish between those that experience rain alone, snow alone, or a mixture of the two. Based on this categorization, the most common form of precipitation throughout the year is rain alone, with a peak probability of 24% on May 29.
Daily Chance of Precipitation
To show variation within the months and not just the monthly totals, we show the rainfall accumulated over a sliding 31-day period centered around each day of the year. John Day experiences some seasonal variation in monthly rainfall.
The rainy period of the year lasts for 9.2 months, from September 30 to July 4, with a sliding 31-day rainfall of at least 0.5 inches. The most rain falls during the 31 days centered around December 6, with an average total accumulation of 1.3 inches.
The rainless period of the year lasts for 2.8 months, from July 4 to September 30. The least rain falls around August 1, with an average total accumulation of 0.3 inches.
Average Monthly Rainfall
We report snowfall in liquid-equivalent terms. The actual depth of new snowfall is typically between 5 and 10 times the liquid-equivalent amount, assuming the ground is frozen. Colder, drier snow tends to be on the higher end of that range and warmer, wetter snow on the lower end.
As with rainfall, we consider the snowfall accumulated over a sliding 31-day period centered around each day of the year. John Day experiences some seasonal variation in monthly liquid-equivalent snowfall.
The snowy period of the year lasts for 3.2 months, from November 15 to February 22, with a sliding 31-day liquid-equivalent snowfall of at least 0.1 inches. The most snow falls during the 31 days centered around December 26, with an average total liquid-equivalent accumulation of 0.3 inches.
The snowless period of the year lasts for 8.8 months, from February 22 to November 15. The least snow falls around August 1, with an average total liquid-equivalent accumulation of 0.0 inches.
Average Liquid-Equivalent Monthly Snowfall
The length of the day in John Day varies significantly over the course of the year. In 2018, the shortest day is December 21, with 8 hours, 50 minutes of daylight; the longest day is June 21, with 15 hours, 32 minutes of daylight.
Hours of Daylight and Twilight
The earliest sunrise is at 5:10 AM on June 15, and the latest sunrise is 2 hours, 25 minutes later at 7:35 AM on November 3. The earliest sunset is at 4:16 PM on December 9, and the latest sunset is 4 hours, 28 minutes later at 8:44 PM on June 26.
Daylight saving time (DST) is observed in John Day during 2018, starting in the spring on March 11, lasting 7.8 months, and ending in the fall on November 4.
Sunrise & Sunset with Twilight and Daylight Saving Time
The perceived humidity level in John Day, as measured by the percentage of time in which the humidity comfort level is muggy, oppressive, or miserable, does not vary significantly over the course of the year, remaining a virtually constant 0% throughout.
Humidity Comfort Levels
The average hourly wind speed in John Day experiences mild seasonal variation over the course of the year.
The windier part of the year lasts for 6.5 months, from October 31 to May 15, with average wind speeds of more than 5.5 miles per hour. The windiest day of the year is December 3, with an average hourly wind speed of 6.3 miles per hour.
The calmer time of year lasts for 5.5 months, from May 15 to October 31. The calmest day of the year is August 11, with an average hourly wind speed of 4.8 miles per hour.
Average Wind Speed
The predominant average hourly wind direction in John Day varies throughout the year.
The wind is most often from the west for 2.8 months, from March 13 to June 7 and for 1.1 months, from September 19 to October 21, with a peak percentage of 43% on March 30. The wind is most often from the north for 3.4 months, from June 7 to September 19, with a peak percentage of 51% on July 21. The wind is most often from the south for 4.7 months, from October 21 to March 13, with a peak percentage of 54% on January 1.
Best Time of Year to Visit
To characterize how pleasant the weather is in John Day throughout the year, we compute two travel scores.
The tourism score favors clear, rainless days with perceived temperatures between 65°F and 80°F. Based on this score, the best time of year to visit John Day for general outdoor tourist activities is from early July to late August, with a peak score in the last week of July.
The beach/pool score favors clear, rainless days with perceived temperatures between 75°F and 90°F. Based on this score, the best time of year to visit John Day for hot-weather activities is from mid July to mid August, with a peak score in the last week of July.
For each hour between 8:00 AM and 9:00 PM of each day in the analysis period (1980 to 2016), 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 0.04 inches of precipitation or more.
Our tourism temperature score is 0 for perceived temperatures below 50°F, rising linearly to 9 for 65°F, to 10 for 75°F, falling linearly to 9 for 80°F, and to 1 for 90°F or hotter.
Our beach/pool temperature score is 0 for perceived temperatures below 65°F, rising linearly to 9 for 75°F, to 10 for 82°F, falling linearly to 9 for 90°F, and to 1 for 100°F or hotter.
The growing season in John Day typically lasts for 5.5 months (168 days), from around April 30 to around October 15, rarely starting before April 8 or after May 21, and rarely ending before September 29 or after November 2.
Time Spent in Various Temperature Bands and the Growing Season
Based on growing degree days alone, the first spring blooms in John Day should appear around April 19, only rarely appearing before April 2 or after May 10.
Growing Degree Days
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 3.1 months, from May 20 to August 23, with an average daily incident shortwave energy per square meter above 6.7 kWh. The brightest day of the year is July 13, with an average of 8.0 kWh.
The darker period of the year lasts for 3.6 months, from October 29 to February 15, with an average daily incident shortwave energy per square meter below 2.8 kWh. The darkest day of the year is December 26, with an average of 1.5 kWh.
Average Daily Incident Shortwave Solar Energy
For the purposes of this report, the geographical coordinates of John Day are 44.416 deg latitude, -118.953 deg longitude, and 3,583 ft elevation.
The topography within 2 miles of John Day contains very significant variations in elevation, with a maximum elevation change of 1,093 feet and an average elevation above sea level of 3,406 feet. Within 10 miles contains very significant variations in elevation (5,171 feet). Within 50 miles also contains extreme variations in elevation (7,244 feet).
The area within 2 miles of John Day is covered by shrubs (92%), within 10 miles by shrubs (69%) and trees (26%), and within 50 miles by shrubs (61%) and trees (35%).
This report illustrates the typical weather in John Day, 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 3 weather stations near enough to contribute to our estimation of the temperature and dew point in John Day.
For each station, the records are corrected for the elevation difference between that station and John Day 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 John Day is computed as the weighted average of the individual contributions from each station, with weights proportional to the inverse of the distance between John Day and a given station.
The stations contributing to this reconstruction are: John Day State Airport (99%, 2.1 kilometers, southwest); Baker Municipal Airport (0.8%, 102 kilometers, northeast); and Meacham, Meacham (0.6%, 129 kilometers, north).
Time zones for aiports and weather stations are provided by AskGeo.com .