Average Weather in Jamestown Kentucky, United States
In Jamestown, the summers are long, warm, and muggy; the winters are short and very cold; and it is wet and partly cloudy year round. Over the course of the year, the temperature typically varies from 27°F to 86°F and is rarely below 11°F or above 93°F.
Based on the tourism score, the best times of year to visit Jamestown for warm-weather activities are from late May to early July and from late July to late September.
The hot season lasts for 3.9 months, from May 25 to September 21, with an average daily high temperature above 78°F. The hottest day of the year is July 21, with an average high of 86°F and low of 67°F.
The cold season lasts for 3.0 months, from November 29 to February 26, with an average daily high temperature below 53°F. The coldest day of the year is January 29, with an average low of 27°F and high of 44°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
Sant'Agata sul Santerno, Italy (4,798 miles away); Negotino, Macedonia (5,338 miles); and Bagratashen, Armenia (6,180 miles) are the far-away foreign places with temperatures most similar to Jamestown (view comparison).
In Jamestown, 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 Jamestown begins around June 14 and lasts for 4.9 months, ending around November 10. On September 21, 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 10 and lasts for 7.1 months, ending around June 14. On January 5, the cloudiest day of the year, the sky is overcast or mostly cloudy 59% of the time, and clear, mostly clear, or partly cloudy 41% 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 Jamestown varies throughout the year.
The wetter season lasts 5.0 months, from March 21 to August 21, with a greater than 34% chance of a given day being a wet day. The chance of a wet day peaks at 43% on June 30.
The drier season lasts 7.0 months, from August 21 to March 21. The smallest chance of a wet day is 24% on October 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 June 30.
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. Jamestown experiences some seasonal variation in monthly rainfall.
Rain falls throughout the year in Jamestown. The most rain falls during the 31 days centered around May 4, with an average total accumulation of 4.6 inches.
The least rain falls around October 20, with an average total accumulation of 2.9 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. Jamestown experiences some seasonal variation in monthly liquid-equivalent snowfall.
The snowy period of the year lasts for 3.6 months, from November 28 to March 15, with a sliding 31-day liquid-equivalent snowfall of at least 0.1 inches. The most snow falls during the 31 days centered around January 25, with an average total liquid-equivalent accumulation of 0.3 inches.
The snowless period of the year lasts for 8.4 months, from March 15 to November 28. The least snow falls around July 24, with an average total liquid-equivalent accumulation of 0.0 inches.
Average Liquid-Equivalent Monthly Snowfall
The length of the day in Jamestown varies significantly over the course of the year. In 2017, the shortest day is December 21, with 9 hours, 37 minutes of daylight; the longest day is June 20, with 14 hours, 42 minutes of daylight.
Hours of Daylight and Twilight
The earliest sunrise is at 5:20 AM on June 13, and the latest sunrise is 1 hour, 48 minutes later at 7:07 AM on November 4. The earliest sunset is at 4:23 PM on December 6, and the latest sunset is 3 hours, 41 minutes later at 8:03 PM on June 28.
Daylight saving time (DST) is observed in Jamestown during 2017, starting in the spring on March 12, lasting 7.8 months, and ending in the fall on November 5.
Sunrise & Sunset with Twilight and Daylight Saving Time
Jamestown experiences extreme seasonal variation in the perceived humidity.
The muggier period of the year lasts for 4.2 months, from May 18 to September 24, during which time the comfort level is muggy, oppressive, or miserable at least 20% of the time. The muggiest day of the year is July 25, with muggy conditions 81% of the time.
The least muggy day of the year is January 30, when muggy conditions are essentially unheard of.
Humidity Comfort Levels
The average hourly wind speed in Jamestown experiences significant seasonal variation over the course of the year.
The windier part of the year lasts for 6.5 months, from October 28 to May 13, with average wind speeds of more than 6.3 miles per hour. The windiest day of the year is February 25, with an average hourly wind speed of 8.0 miles per hour.
The calmer time of year lasts for 5.5 months, from May 13 to October 28. The calmest day of the year is August 1, with an average hourly wind speed of 4.6 miles per hour.
Average Wind Speed
The predominant average hourly wind direction in Jamestown varies throughout the year.
The wind is most often from the west for 1.6 months, from January 5 to February 22 and for 1.8 months, from June 23 to August 16, with a peak percentage of 40% on July 13. The wind is most often from the south for 4.0 months, from February 22 to June 23 and for 4.6 months, from August 16 to January 5, with a peak percentage of 38% on May 19.
Best Time of Year to Visit
To characterize how pleasant the weather is in Jamestown 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 Jamestown for general outdoor tourist activities are from late May to early July and from late July to late September, with a peak score in the first 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 Jamestown for hot-weather activities is from mid June to early September, 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 Jamestown typically lasts for 6.3 months (193 days), from around April 12 to around October 21, rarely starting before March 26 or after April 28, and rarely ending before October 2 or after November 9.
Time Spent in Various Temperature Bands and the Growing Season
Based on growing degree days alone, the first spring blooms in Jamestown should appear around March 6, only rarely appearing before February 17 or after March 26.
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 4.5 months, from April 20 to September 3, with an average daily incident shortwave energy per square meter above 5.7 kWh. The brightest day of the year is June 22, with an average of 6.6 kWh.
The darker period of the year lasts for 3.0 months, from November 10 to February 9, with an average daily incident shortwave energy per square meter below 3.0 kWh. The darkest day of the year is December 24, with an average of 2.1 kWh.
Average Daily Incident Shortwave Solar Energy
For the purposes of this report, the geographical coordinates of Jamestown are 36.985 deg latitude, -85.063 deg longitude, and 935 ft elevation.
The topography within 2 miles of Jamestown contains only modest variations in elevation, with a maximum elevation change of 295 feet and an average elevation above sea level of 915 feet. Within 10 miles contains only modest variations in elevation (594 feet). Within 50 miles contains significant variations in elevation (1,896 feet).
The area within 2 miles of Jamestown is covered by cropland (68%) and trees (28%), within 10 miles by cropland (53%) and trees (33%), and within 50 miles by trees (55%) and cropland (42%).
This report illustrates the typical weather in Jamestown, 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 Jamestown.
For each station, the records are corrected for the elevation difference between that station and Jamestown 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 Jamestown is computed as the weighted average of the individual contributions from each station, with weights proportional to the inverse of the distance between Jamestown and a given station.
The stations contributing to this reconstruction are: Wayne County Airport (74%, 23 kilometers, southeast); Stuart Powell Field (14%, 71 kilometers, north); and Glasgow Municipal Airport (12%, 79 kilometers, west).
Time zones for aiports and weather stations are provided by AskGeo.com .