Climate and Average Weather Year Round in Fort Smith Arkansas, United States
In Fort Smith, the summers are hot and muggy; the winters are short, very cold, and wet; and it is partly cloudy year round. Over the course of the year, the temperature typically varies from 31°F to 94°F and is rarely below 18°F or above 101°F.
Based on the beach/pool score, the best time of year to visit Fort Smith for hot-weather activities is from mid June to early September.
Climate in Fort Smith
Average Temperature in Fort Smith
The hot season lasts for 3.5 months, from June 3 to September 18, with an average daily high temperature above 85°F. The hottest day of the year is July 26, with an average high of 94°F and low of 73°F.
The cold season lasts for 2.9 months, from November 27 to February 23, with an average daily high temperature below 58°F. The coldest day of the year is January 7, with an average low of 31°F and high of 50°F.
Average High and Low Temperature in Fort Smith
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 Smith
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
’Aïn el Bell, Algeria (5,275 miles away); Kafr Takhārīm, Syria (6,582 miles); and Shahrisabz, Uzbekistan (7,163 miles) are the far-away foreign places with temperatures most similar to Fort Smith (view comparison).
In Fort Smith, the average percentage of the sky covered by clouds experiences mild seasonal variation over the course of the year.
The clearer part of the year in Fort Smith begins around June 11 and lasts for 4.9 months, ending around November 7. On October 5, the clearest day of the year, the sky is clear, mostly clear, or partly cloudy 71% of the time, and overcast or mostly cloudy 29% of the time.
The cloudier part of the year begins around November 7 and lasts for 7.1 months, ending around June 11. On February 16, the cloudiest day of the year, the sky is overcast or mostly cloudy 48% of the time, and clear, mostly clear, or partly cloudy 52% of the time.
Cloud Cover Categories in Fort Smith
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 Smith varies throughout the year.
The wetter season lasts 3.0 months, from April 3 to July 2, with a greater than 30% chance of a given day being a wet day. The chance of a wet day peaks at 43% on May 21.
The drier season lasts 9.0 months, from July 2 to April 3. The smallest chance of a wet day is 17% on January 12.
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 43% on May 21.
Daily Chance of Precipitation in Fort Smith
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 Smith experiences significant seasonal variation in monthly rainfall.
Rain falls throughout the year in Fort Smith. The most rain falls during the 31 days centered around May 10, with an average total accumulation of 5.3 inches.
The least rain falls around January 21, with an average total accumulation of 2.2 inches.
Average Monthly Rainfall in Fort Smith
The sliding 31-day liquid-equivalent quantity of snowfall in Fort Smith does not vary significantly over the course of the year, staying within 0.1 inches of 0.1 inches throughout.
Average Liquid-Equivalent Monthly Snowfall in Fort Smith
The length of the day in Fort Smith varies significantly over the course of the year. In 2021, the shortest day is December 21, with 9 hours, 46 minutes of daylight; the longest day is June 20, with 14 hours, 33 minutes of daylight.
Hours of Daylight and Twilight in Fort Smith
The earliest sunrise is at 6:01 AM on June 12, and the latest sunrise is 1 hour, 42 minutes later at 7:44 AM on November 6. The earliest sunset is at 5:04 PM on December 5, and the latest sunset is 3 hours, 32 minutes later at 8:36 PM on June 28.
Daylight saving time (DST) is observed in Fort Smith during 2021, starting in the spring on March 14, lasting 7.8 months, and ending in the fall on November 7.
Sunrise & Sunset with Twilight and Daylight Saving Time in Fort Smith
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 Smith
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.
Fort Smith experiences extreme seasonal variation in the perceived humidity.
The muggier period of the year lasts for 4.6 months, from May 12 to September 30, during which time the comfort level is muggy, oppressive, or miserable at least 21% of the time. The muggiest day of the year is July 22, with muggy conditions 85% of the time.
The least muggy day of the year is February 19, when muggy conditions are essentially unheard of.
Humidity Comfort Levels in Fort Smith
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 Smith experiences significant seasonal variation over the course of the year.
The windier part of the year lasts for 7.0 months, from October 19 to May 21, with average wind speeds of more than 6.4 miles per hour. The windiest day of the year is April 1, with an average hourly wind speed of 7.9 miles per hour.
The calmer time of year lasts for 5.0 months, from May 21 to October 19. The calmest day of the year is August 3, with an average hourly wind speed of 4.8 miles per hour.
Average Wind Speed in Fort Smith
The predominant average hourly wind direction in Fort Smith varies throughout the year.
The wind is most often from the south for 6.6 months, from February 22 to September 9 and for 3.2 months, from September 17 to December 23, with a peak percentage of 55% on June 24. The wind is most often from the east for 1.1 weeks, from September 9 to September 17, with a peak percentage of 36% on September 9. The wind is most often from the north for 2.0 months, from December 23 to February 22, with a peak percentage of 31% on January 1.
Wind Direction in Fort Smith
Best Time of Year to Visit
To characterize how pleasant the weather is in Fort Smith 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 times of year to visit Fort Smith for general outdoor tourist activities are from early May to late June and from mid August to mid October, with a peak score in the third week of September.
Tourism Score in Fort Smith
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 Smith for hot-weather activities is from mid June to early September, with a peak score in the first week of July.
Beach/Pool Score in Fort Smith
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 Smith typically lasts for 7.5 months (230 days), from around March 24 to around November 9, rarely starting before March 2 or after April 15, and rarely ending before October 21 or after November 29.
Time Spent in Various Temperature Bands and the Growing Season in Fort Smith
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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 Smith should appear around February 18, only rarely appearing before February 2 or after March 7.
Growing Degree Days in Fort Smith
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 significant seasonal variation over the course of the year.
The brighter period of the year lasts for 4.1 months, from April 24 to August 27, with an average daily incident shortwave energy per square meter above 6.1 kWh. The brightest day of the year is July 12, with an average of 7.0 kWh.
The darker period of the year lasts for 3.0 months, from November 8 to February 7, with an average daily incident shortwave energy per square meter below 3.3 kWh. The darkest day of the year is December 23, with an average of 2.4 kWh.
Average Daily Incident Shortwave Solar Energy in Fort Smith
For the purposes of this report, the geographical coordinates of Fort Smith are 35.386 deg latitude, -94.399 deg longitude, and 427 ft elevation.
The topography within 2 miles of Fort Smith contains only modest variations in elevation, with a maximum elevation change of 233 feet and an average elevation above sea level of 459 feet. Within 10 miles contains only modest variations in elevation (748 feet). Within 50 miles contains significant variations in elevation (2,418 feet).
The area within 2 miles of Fort Smith is covered by artificial surfaces (100%), within 10 miles by cropland (47%) and artificial surfaces (26%), and within 50 miles by trees (57%) and cropland (37%).
This report illustrates the typical weather in Fort Smith, 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 Fort Smith.
For each station, the records are corrected for the elevation difference between that station and Fort Smith 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 Fort Smith is computed as the weighted average of the individual contributions from each station, with weights proportional to the inverse of the distance between Fort Smith and a given station.
The stations contributing to this reconstruction are: Fort Smith Municipal Airport (KFSM, 91%, 7 kilometers, southeast); Sallisaw Municipal Airport (KJSV, 7%, 37 kilometers, west); and Drake Field (KFYV, 2.4%, 73 kilometers, north).
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.