Average Weather in May in Fort Thompson South Dakota, United States
Daily high temperatures increase by 9°F, from 67°F to 76°F, rarely falling below 52°F or exceeding 87°F.
Daily low temperatures increase by 11°F, from 44°F to 54°F, rarely falling below 33°F or exceeding 64°F.
For reference, on July 19, the hottest day of the year, temperatures in Fort Thompson typically range from 65°F to 89°F, while on January 2, the coldest day of the year, they range from 12°F to 29°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 Fort Thompson experiences essentially constant cloud cover, with the percentage of time that the sky is overcast or mostly cloudy remaining about 46% throughout the month.
The clearest day of the month is May 29, with clear, mostly clear, or partly cloudy conditions 56% of the time.
For reference, on March 15, the cloudiest day of the year, the chance of overcast or mostly cloudy conditions is 54%, while on July 25, the clearest day of the year, the chance of clear, mostly clear, or partly cloudy skies is 76%.
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 Fort Thompson, the chance of a wet day over the course of May is very rapidly increasing, starting the month at 25% and ending it at 35%.
For reference, the year's highest daily chance of a wet day is 38% on June 7, and its lowest chance is 3% on January 22.
Probability of Precipitation in May
The average sliding 31-day rainfall during May in Fort Thompson is increasing, starting the month at 2.5 inches, when it rarely exceeds 4.6 inches or falls below 0.5 inches, and ending the month at 3.2 inches, when it rarely exceeds 5.7 inches or falls below 1.1 inches.
Average Monthly Rainfall in May
Over the course of May in Fort Thompson, the length of the day is rapidly increasing. From the start to the end of the month, the length of the day increases by 1 hour, 3 minutes, implying an average daily increase of 2 minutes, 5 seconds, and weekly increase of 14 minutes, 35 seconds.
The shortest day of the month is May 1, with 14 hours, 13 minutes of daylight and the longest day is May 31, with 15 hours, 15 minutes of daylight.
Hours of Daylight and Twilight in May
The latest sunrise of the month in Fort Thompson is 6:28 AM on May 1 and the earliest sunrise is 31 minutes earlier at 5:58 AM on May 31.
The earliest sunset is 8:41 PM on May 1 and the latest sunset is 32 minutes later at 9:13 PM on May 31.
Daylight saving time is observed in Fort Thompson during 2021, 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 5:54 AM and sets 15 hours, 30 minutes later, at 9:24 PM, while on December 21, the shortest day of the year, it rises at 8:09 AM and sets 8 hours, 53 minutes later, at 5:02 PM.
Sunrise & Sunset with Twilight in May
The figure below presents a compact representation of key lunar data for May 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. The label associated with each bar indicates the date and time that the phase is obtained, and the companion time labels indicate the rise and set times of the Moon for the nearest time interval in which the moon is above the horizon.
Moon Rise, Set & Phases in May
The chance that a given day will be muggy in Fort Thompson is gradually increasing during May, rising from 0% to 3% over the course of the month.
For reference, on July 25, the muggiest day of the year, there are muggy conditions 29% of the time, while on January 1, 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 Fort Thompson is gradually decreasing during May, decreasing from 12.0 miles per hour to 11.2 miles per hour over the course of the month.
For reference, on April 8, the windiest day of the year, the daily average wind speed is 12.5 miles per hour, while on July 26, the calmest day of the year, the daily average wind speed is 9.6 miles per hour.
Average Wind Speed in May
The wind direction in Fort Thompson during May is predominantly out of the north from May 1 to May 11 and the south from May 11 to May 31.
Wind Direction in May
The growing season in Fort Thompson typically lasts for 5.4 months (163 days), from around April 28 to around October 8, rarely starting before April 7 or after May 19, and rarely ending before September 20 or after October 27.
The month of May in Fort Thompson is more likely than not fully within the growing season, with the chance that a given day is in the growing season rapidly increasing from 56% to 99% over the course of the month.
Time Spent in Various Temperature Bands and the Growing Season in May
The average accumulated growing degree days in Fort Thompson are increasing during May, increasing by 312°F, from 180°F to 492°F, over the course of the month.
Growing Degree Days in May
The average daily incident shortwave solar energy in Fort Thompson is gradually increasing during May, rising by 0.7 kWh, from 6.1 kWh to 6.8 kWh, over the course of the month.
Average Daily Incident Shortwave Solar Energy in May
For the purposes of this report, the geographical coordinates of Fort Thompson are 44.069 deg latitude, -99.438 deg longitude, and 1,444 ft elevation.
The topography within 2 miles of Fort Thompson contains only modest variations in elevation, with a maximum elevation change of 302 feet and an average elevation above sea level of 1,447 feet. Within 10 miles contains only modest variations in elevation (656 feet). Within 50 miles contains significant variations in elevation (1,014 feet).
The area within 2 miles of Fort Thompson is covered by grassland (55%), cropland (23%), and water (22%), within 10 miles by grassland (72%) and water (14%), and within 50 miles by grassland (69%) and cropland (28%).
This report illustrates the typical weather in Fort Thompson, 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 Thompson.
For each station, the records are corrected for the elevation difference between that station and Fort Thompson 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 Thompson is computed as the weighted average of the individual contributions from each station, with weights proportional to the inverse of the distance between Fort Thompson and a given station.
The stations contributing to this reconstruction are: Chamberlain, Chamberlain Municipal Airport (66%, 35 kilometers, south); Pierre Municipal Airport (21%, 76 kilometers, northwest); and Huron Regional Airport (13%, 104 kilometers, east).
Time zones for airports and weather stations are provided by AskGeo.com .