Climate and Average Weather Year Round in Fort St. John Canada
In Fort St. John, the summers are comfortable and partly cloudy and the winters are frigid, snowy, and mostly cloudy. Over the course of the year, the temperature typically varies from 3°F to 73°F and is rarely below -22°F or above 82°F.
Based on the tourism score, the best time of year to visit Fort St. John for warm-weather activities is from early July to mid August.
Climate in Fort St. John
Average Temperature in Fort St. John
The warm season lasts for 3.8 months, from May 18 to September 13, with an average daily high temperature above 62°F. The hottest day of the year is July 30, with an average high of 73°F and low of 53°F.
The cold season lasts for 3.6 months, from November 15 to March 2, with an average daily high temperature below 28°F. The coldest day of the year is January 11, with an average low of 3°F and high of 17°F.
Average High and Low Temperature in Fort St. John
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 Fort St. John
frigid 15°F freezing 32°F very cold 45°F cold 55°F cool 65°F comfortable 75°F warm 85°F hot 95°F sweltering
In Fort St. John, 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 Fort St. John begins around April 22 and lasts for 5.5 months, ending around October 5. On August 4, the clearest day of the year, the sky is clear, mostly clear, or partly cloudy 54% of the time, and overcast or mostly cloudy 46% of the time.
The cloudier part of the year begins around October 5 and lasts for 6.6 months, ending around April 22. On February 17, the cloudiest day of the year, the sky is overcast or mostly cloudy 73% of the time, and clear, mostly clear, or partly cloudy 27% of the time.
Cloud Cover Categories in Fort St. John
0% clear 20% mostly clear 40% partly cloudy 60% mostly cloudy 80% overcast 100%
A wet day is one with at least 0.04 inches of liquid or liquid-equivalent precipitation. The chance of wet days in Fort St. John varies throughout the year.
The wetter season lasts 6.2 months, from May 21 to November 29, with a greater than 21% chance of a given day being a wet day. The chance of a wet day peaks at 30% on July 4.
The drier season lasts 5.8 months, from November 29 to May 21. The smallest chance of a wet day is 13% on April 5.
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 in Fort St. John changes throughout the year.
Rain alone is the most common for 6.8 months, from April 3 to October 26. The highest chance of a day with rain alone is 30% on July 4.
Snow alone is the most common for 5.2 months, from October 26 to April 3. The highest chance of a day with snow alone is 18% on November 19.
Daily Chance of Precipitation in Fort St. John
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. Fort St. John experiences significant seasonal variation in monthly rainfall.
The rainy period of the year lasts for 6.7 months, from April 11 to November 2, with a sliding 31-day rainfall of at least 0.5 inches. The most rain falls during the 31 days centered around June 27, with an average total accumulation of 2.8 inches.
The rainless period of the year lasts for 5.3 months, from November 2 to April 11. The least rain falls around February 17, with an average total accumulation of 0.1 inches.
Average Monthly Rainfall in Fort St. John
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. Fort St. John experiences some seasonal variation in monthly liquid-equivalent snowfall.
The snowy period of the year lasts for 7.5 months, from September 23 to May 6, with a sliding 31-day liquid-equivalent snowfall of at least 0.1 inches. The most snow falls during the 31 days centered around November 19, with an average total liquid-equivalent accumulation of 0.9 inches.
The snowless period of the year lasts for 4.6 months, from May 6 to September 23. The least snow falls around July 13, with an average total liquid-equivalent accumulation of 0.0 inches.
Average Liquid-Equivalent Monthly Snowfall in Fort St. John
The length of the day in Fort St. John varies extremely over the course of the year. In 2021, the shortest day is December 21, with 6 hours, 53 minutes of daylight; the longest day is June 20, with 17 hours, 41 minutes of daylight.
Hours of Daylight and Twilight in Fort St. John
The earliest sunrise is at 4:14 AM on June 18, and the latest sunrise is 5 hours, 22 minutes later at 9:36 AM on December 28. The earliest sunset is at 4:26 PM on December 14, and the latest sunset is 5 hours, 29 minutes later at 9:56 PM on June 23.
Daylight saving time (DST) is not observed in Fort St. John during 2021.
Sunrise & Sunset with Twilight in Fort St. John
The figure below presents a compact representation of key lunar data for 2021. The horizontal axis is the day, the vertical axis is the hour of the day, and the colored areas indicate when the moon is above the horizon. The vertical gray bars (new Moons) and blue bars (full Moons) indicate key Moon phases.
Moon Rise, Set & Phases in Fort St. John
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 perceived humidity level in Fort St. John, 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 in Fort St. John
dry 55°F comfortable 60°F humid 65°F muggy 70°F oppressive 75°F miserable
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 Fort St. John experiences mild seasonal variation over the course of the year.
The windier part of the year lasts for 7.7 months, from September 26 to May 18, with average wind speeds of more than 4.4 miles per hour. The windiest day of the year is April 20, with an average hourly wind speed of 5.0 miles per hour.
The calmer time of year lasts for 4.3 months, from May 18 to September 26. The calmest day of the year is August 1, with an average hourly wind speed of 3.9 miles per hour.
Average Wind Speed in Fort St. John
The predominant average hourly wind direction in Fort St. John is from the west throughout the year.
Wind Direction in Fort St. John
Best Time of Year to Visit
To characterize how pleasant the weather is in Fort St. John 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 Fort St. John for general outdoor tourist activities is from early July to mid August, with a peak score in the last week of July.
Tourism Score in Fort St. John
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 Fort St. John for hot-weather activities is from mid July to early August, with a peak score in the first week of August.
Beach/Pool Score in Fort St. John
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.
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 Fort St. John typically lasts for 4.3 months (132 days), from around May 11 to around September 20, rarely starting before April 19 or after May 30, and rarely ending before September 1 or after October 9.
Time Spent in Various Temperature Bands and the Growing Season in Fort St. John
frigid 15°F freezing 32°F very cold 45°F cold 55°F cool 65°F comfortable 75°F warm 85°F hot 95°F sweltering
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.
Based on growing degree days alone, the first spring blooms in Fort St. John should appear around May 18, only rarely appearing before May 7 or after June 1.
Growing Degree Days in Fort St. John
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 3.6 months, from April 29 to August 17, with an average daily incident shortwave energy per square meter above 5.1 kWh. The brightest day of the year is June 14, with an average of 6.3 kWh.
The darker period of the year lasts for 3.9 months, from October 21 to February 18, with an average daily incident shortwave energy per square meter below 1.6 kWh. The darkest day of the year is December 19, with an average of 0.4 kWh.
Average Daily Incident Shortwave Solar Energy in Fort St. John
For the purposes of this report, the geographical coordinates of Fort St. John are 56.250 deg latitude, -120.853 deg longitude, and 2,280 ft elevation.
The topography within 2 miles of Fort St. John contains only modest variations in elevation, with a maximum elevation change of 427 feet and an average elevation above sea level of 2,241 feet. Within 10 miles contains only modest variations in elevation (1,516 feet). Within 50 miles contains very significant variations in elevation (3,173 feet).
The area within 2 miles of Fort St. John is covered by sparse vegetation (46%), cropland (35%), and artificial surfaces (17%), within 10 miles by cropland (43%) and trees (39%), and within 50 miles by trees (62%) and cropland (27%).
This report illustrates the typical weather in Fort St. John, 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 is only a single weather station, Fort St. John Airport, in our network suitable to be used as a proxy for the historical temperature and dew point records of Fort St. John.
At a distance of 7 kilometers from Fort St. John, closer than our threshold of 150 kilometers, this station is deemed sufficiently nearby to be relied upon as our primary source for temperature and dew point records.
The station records are corrected for the elevation difference between the station and Fort St. John according to the International Standard Atmosphere , and by the relative change present in the MERRA-2 satellite-era reanalysis between the two locations.
Please note that the station records themselves may additionally have been back-filled using other nearby stations or the MERRA-2 reanalysis.
All data relating to the Sun's position (e.g., sunrise and sunset) are computed using astronomical formulas from the book, Astronomical Algorithms 2nd Edition , 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 airports 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.