Average Weather in May in Jefferson Texas, United States
Daily high temperatures increase by 7°F, from 79°F to 86°F, rarely falling below 71°F or exceeding 92°F.
Daily low temperatures increase by 8°F, from 59°F to 67°F, rarely falling below 49°F or exceeding 73°F.
For reference, on July 31, the hottest day of the year, temperatures in Jefferson typically range from 73°F to 94°F, while on January 7, the coldest day of the year, they range from 38°F to 56°F.
Average High and Low Temperature in May
The figure below shows you a compact characterization of the hourly average temperatures for the quarter of the year centered on May. The horizontal axis is the day, 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 May
The month of May in Jefferson experiences essentially constant cloud cover, with the percentage of time that the sky is overcast or mostly cloudy remaining about 41% throughout the month. The highest chance of overcast or mostly cloudy conditions is 43% on May 15.
The clearest day of the month is May 31, with clear, mostly clear, or partly cloudy conditions 61% of the time.
For reference, on February 16, the cloudiest day of the year, the chance of overcast or mostly cloudy conditions is 49%, while on October 5, the clearest day of the year, the chance of clear, mostly clear, or partly cloudy skies is 72%.
Cloud Cover Categories in May
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. In Jefferson, the chance of a wet day over the course of May is essentially constant, remaining around 35% throughout.
For reference, the year's highest daily chance of a wet day is 36% on June 10, and its lowest chance is 22% on September 20.
Probability of Precipitation in May
The average sliding 31-day rainfall during May in Jefferson is gradually decreasing, starting the month at 4.2 inches, when it rarely exceeds 7.6 inches or falls below 1.3 inches, and ending the month at 3.9 inches, when it rarely exceeds 6.8 inches or falls below 1.3 inches.
The highest average 31-day accumulation is 4.3 inches on May 3.
Average Monthly Rainfall in May
Over the course of May in Jefferson, the length of the day is increasing. From the start to the end of the month, the length of the day increases by 40 minutes, implying an average daily increase of 1 minute, 21 seconds, and weekly increase of 9 minutes, 27 seconds.
The shortest day of the month is May 1, with 13 hours, 29 minutes of daylight and the longest day is May 31, with 14 hours, 9 minutes of daylight.
Hours of Daylight and Twilight in May
The latest sunrise of the month in Jefferson is 6:30 AM on May 1 and the earliest sunrise is 20 minutes earlier at 6:10 AM on May 31.
The earliest sunset is 7:59 PM on May 1 and the latest sunset is 21 minutes later at 8:19 PM on May 31.
Daylight saving time is observed in Jefferson during 2018, but it neither starts nor ends during May, so the entire month is in daylight saving time.
For reference, on June 21, the longest day of the year, the Sun rises at 6:09 AM and sets 14 hours, 19 minutes later, at 8:28 PM, while on December 21, the shortest day of the year, it rises at 7:15 AM and sets 10 hours, 0 minutes later, at 5:15 PM.
Sunrise & Sunset with Twilight in May
The chance that a given day will be muggy in Jefferson is very rapidly increasing during May, rising from 26% to 66% over the course of the month.
For reference, on July 14, the muggiest day of the year, there are muggy conditions 94% of the time, while on January 28, the least muggy day of the year, there are muggy conditions 0% of the time.
Humidity Comfort Levels in May
dry 55°F comfortable 60°F humid 65°F muggy 70°F oppressive 75°F miserable
The average hourly wind speed in Jefferson is gradually decreasing during May, decreasing from 5.5 miles per hour to 4.8 miles per hour over the course of the month.
For reference, on April 1, the windiest day of the year, the daily average wind speed is 6.0 miles per hour, while on July 30, the calmest day of the year, the daily average wind speed is 4.0 miles per hour.
Average Wind Speed in May
Wind Direction in May
The growing season in Jefferson typically lasts for 8.3 months (255 days), from around March 10 to around November 20, rarely starting before February 13 or after April 2, and rarely ending before October 30 or after December 10.
The month of May in Jefferson is reliably fully within the growing season.
Time Spent in Various Temperature Bands and the Growing Season in May
The average accumulated growing degree days in Jefferson are rapidly increasing during May, increasing by 658°F, from 992°F to 1,650°F, over the course of the month.
Growing Degree Days in May
The average daily incident shortwave solar energy in Jefferson is essentially constant during May, remaining within 0.2 kWh of 6.4 kWh throughout.
Average Daily Incident Shortwave Solar Energy in May
For the purposes of this report, the geographical coordinates of Jefferson are 32.757 deg latitude, -94.345 deg longitude, and 190 ft elevation.
The topography within 2 miles of Jefferson contains only modest variations in elevation, with a maximum elevation change of 131 feet and an average elevation above sea level of 204 feet. Within 10 miles also contains only modest variations in elevation (259 feet). Within 50 miles contains only modest variations in elevation (535 feet).
The area within 2 miles of Jefferson is covered by herbaceous vegetation (36%), trees (35%), shrubs (14%), and cropland (11%), within 10 miles by trees (58%) and herbaceous vegetation (24%), and within 50 miles by trees (44%) and cropland (34%).
This report illustrates the typical weather in Jefferson year round, 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 Jefferson.
For each station, the records are corrected for the elevation difference between that station and Jefferson 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 Jefferson is computed as the weighted average of the individual contributions from each station, with weights proportional to the inverse of the distance between Jefferson and a given station.
The stations contributing to this reconstruction are: Harrison County Airport (57%, 27 kilometers, south); Gilmer, Fox Stephens Field - Gilmer Municipal Airport (18%, 57 kilometers, west); Mount Pleasant, Mount Pleasant Regional Airport (14%, 69 kilometers, northwest); and Texarkana Regional Airport (10%, 84 kilometers, north).
Time zones for aiports and weather stations are provided by AskGeo.com .