Average Weather in Harrison Tennessee, United States
In Harrison, 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 32°F to 89°F and is rarely below 19°F or above 95°F.
Based on the tourism score, the best times of year to visit Harrison for warm-weather activities are from mid May to mid June and from mid August to early October.
The hot season lasts for 3.8 months, from May 25 to September 19, with an average daily high temperature above 81°F. The hottest day of the year is July 21, with an average high of 89°F and low of 71°F.
The cool season lasts for 2.9 months, from November 28 to February 25, with an average daily high temperature below 57°F. The coldest day of the year is January 26, with an average low of 32°F and high of 50°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 Harrison, 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 Harrison begins around June 14 and lasts for 5.1 months, ending around November 19. On September 20, the clearest day of the year, the sky is clear, mostly clear, or partly cloudy 67% of the time, and overcast or mostly cloudy 33% of the time.
The cloudier part of the year begins around November 19 and lasts for 6.9 months, ending around June 14. On January 3, the cloudiest day of the year, the sky is overcast or mostly cloudy 55% of the time, and clear, mostly clear, or partly cloudy 45% 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 Harrison varies throughout the year.
The wetter season lasts 5.7 months, from March 1 to August 24, with a greater than 32% chance of a given day being a wet day. The chance of a wet day peaks at 43% on July 9.
The drier season lasts 6.3 months, from August 24 to March 1. The smallest chance of a wet day is 20% on October 16.
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 July 9.
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. Harrison experiences significant seasonal variation in monthly rainfall.
Rain falls throughout the year in Harrison. The most rain falls during the 31 days centered around December 2, with an average total accumulation of 4.9 inches.
The least rain falls around August 22, with an average total accumulation of 2.8 inches.
Average Monthly Rainfall
The sliding 31-day liquid-equivalent quantity of snowfall in Harrison 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
The length of the day in Harrison varies significantly over the course of the year. In 2018, the shortest day is December 21, with 9 hours, 48 minutes of daylight; the longest day is June 21, with 14 hours, 31 minutes of daylight.
Hours of Daylight and Twilight
The earliest sunrise is at 6:25 AM on June 12, and the latest sunrise is 1 hour, 38 minutes later at 8:03 AM on November 3. The earliest sunset is at 5:28 PM on December 5, and the latest sunset is 3 hours, 31 minutes later at 8:58 PM on June 29.
Daylight saving time (DST) is observed in Harrison 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
Harrison experiences extreme seasonal variation in the perceived humidity.
The muggier period of the year lasts for 4.3 months, from May 20 to September 28, 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 25, with muggy conditions 85% of the time.
The least muggy day of the year is January 23, when muggy conditions are essentially unheard of.
Humidity Comfort Levels
The average hourly wind speed in Harrison experiences mild seasonal variation over the course of the year.
The windier part of the year lasts for 6.6 months, from October 27 to May 13, with average wind speeds of more than 4.4 miles per hour. The windiest day of the year is February 26, with an average hourly wind speed of 5.6 miles per hour.
The calmer time of year lasts for 5.4 months, from May 13 to October 27. The calmest day of the year is August 1, with an average hourly wind speed of 3.2 miles per hour.
Average Wind Speed
The predominant average hourly wind direction in Harrison varies throughout the year.
The wind is most often from the north for 2.3 weeks, from January 21 to February 6; for 1.7 weeks, from February 11 to February 23; and for 2.3 weeks, from July 28 to August 13, with a peak percentage of 35% on January 29. The wind is most often from the south for 5.0 days, from February 6 to February 11; for 4.2 months, from February 23 to June 30; and for 5.3 months, from August 13 to January 21, with a peak percentage of 42% on May 4. The wind is most often from the west for 4.0 weeks, from June 30 to July 28, with a peak percentage of 34% on July 14.
Best Time of Year to Visit
To characterize how pleasant the weather is in Harrison 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 Harrison for general outdoor tourist activities are from mid May to mid June and from mid August to early October, with a peak score in the third week of September.
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 Harrison for hot-weather activities is from mid June to early September, with a peak score in the second week of August.
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 Harrison typically lasts for 7.4 months (228 days), from around March 26 to around November 9, rarely starting before March 5 or after April 15, and rarely ending before October 22 or after November 27.
Time Spent in Various Temperature Bands and the Growing Season
Based on growing degree days alone, the first spring blooms in Harrison should appear around February 23, only rarely appearing before February 7 or after March 12.
Growing Degree Days
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 4.6 months, from April 14 to September 2, with an average daily incident shortwave energy per square meter above 5.8 kWh. The brightest day of the year is June 23, with an average of 6.7 kWh.
The darker period of the year lasts for 2.8 months, from November 12 to February 6, with an average daily incident shortwave energy per square meter below 3.2 kWh. The darkest day of the year is December 24, with an average of 2.4 kWh.
Average Daily Incident Shortwave Solar Energy
For the purposes of this report, the geographical coordinates of Harrison are 35.114 deg latitude, -85.138 deg longitude, and 764 ft elevation.
The topography within 2 miles of Harrison contains only modest variations in elevation, with a maximum elevation change of 374 feet and an average elevation above sea level of 785 feet. Within 10 miles contains only modest variations in elevation (1,378 feet). Within 50 miles contains very significant variations in elevation (3,720 feet).
The area within 2 miles of Harrison is covered by trees (67%) and artificial surfaces (12%), within 10 miles by trees (49%) and artificial surfaces (27%), and within 50 miles by trees (70%) and cropland (23%).
This report illustrates the typical weather in Harrison, 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 Harrison.
For each station, the records are corrected for the elevation difference between that station and Harrison 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 Harrison is computed as the weighted average of the individual contributions from each station, with weights proportional to the inverse of the distance between Harrison and a given station.
The stations contributing to this reconstruction are: Lovell Field (92%, 11 kilometers, southwest); Crossville Memorial Airport (3.4%, 93 kilometers, north); Western Carolina Regional Airport (2.5%, 116 kilometers, east); and McGhee Tyson Airport (2.2%, 131 kilometers, northeast).
Time zones for aiports and weather stations are provided by AskGeo.com .