Average Weather in Mount Vernon Indiana, United States
In Mount Vernon, the summers are long, warm, humid, and wet; the winters are freezing and windy; and it is partly cloudy year round. Over the course of the year, the temperature typically varies from 21°F to 85°F and is rarely below 3°F or above 92°F.
The warm season lasts for 4.0 months, from May 22 to September 22, with an average daily high temperature above 74°F. The hottest day of the year is July 19, with an average high of 85°F and low of 66°F.
The cold season lasts for 3.2 months, from November 30 to March 4, with an average daily high temperature below 45°F. The coldest day of the year is January 29, with an average low of 21°F and high of 34°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 Mount Vernon, 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 Mount Vernon begins around June 10 and lasts for 4.7 months, ending around November 1. On August 23, the clearest day of the year, the sky is clear, mostly clear, or partly cloudy 69% of the time, and overcast or mostly cloudy 31% of the time.
The cloudier part of the year begins around November 1 and lasts for 7.3 months, ending around June 10. On January 2, the cloudiest day of the year, the sky is overcast or mostly cloudy 61% of the time, and clear, mostly clear, or partly cloudy 39% of the time.
A wet day is one with at least 0.04 inches of liquid or liquid-equivalent precipitation. The chance of wet days in Mount Vernon varies throughout the year.
The wetter season lasts 5.3 months, from March 30 to September 8, with a greater than 30% chance of a given day being a wet day. The chance of a wet day peaks at 41% on May 28.
The drier season lasts 6.7 months, from September 8 to March 30. The smallest chance of a wet day is 18% on February 5.
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 41% on May 28.
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. Mount Vernon experiences significant seasonal variation in monthly rainfall.
Rain falls throughout the year in Mount Vernon. The most rain falls during the 31 days centered around June 8, with an average total accumulation of 4.0 inches.
The least rain falls around February 3, with an average total accumulation of 1.3 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. Mount Vernon experiences some seasonal variation in monthly liquid-equivalent snowfall.
The snowy period of the year lasts for 4.1 months, from November 29 to March 31, 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 31, with an average total liquid-equivalent accumulation of 0.4 inches.
The snowless period of the year lasts for 8.0 months, from March 31 to November 29. The least snow falls around July 27, with an average total liquid-equivalent accumulation of 0.0 inches.
Average Liquid-Equivalent Monthly Snowfall
The length of the day in Mount Vernon varies significantly over the course of the year. In 2017, the shortest day is December 21, with 9 hours, 16 minutes of daylight; the longest day is June 21, with 15 hours, 5 minutes of daylight.
Hours of Daylight and Twilight
The earliest sunrise is at 6:11 AM on June 14, and the latest sunrise is 2 hours, 6 minutes later at 8:17 AM on November 4. The earliest sunset is at 5:15 PM on December 7, and the latest sunset is 4 hours, 3 minutes later at 9:18 PM on June 27.
Daylight saving time (DST) is observed in Mount Vernon 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
Mount Vernon experiences extreme seasonal variation in the perceived humidity.
The muggier period of the year lasts for 3.7 months, from May 28 to September 19, during which time the comfort level is muggy, oppressive, or miserable at least 13% of the time. The muggiest day of the year is July 22, with muggy conditions 50% of the time.
The least muggy day of the year is February 10, when muggy conditions are essentially unheard of.
Humidity Comfort Levels
The average hourly wind speed in Mount Vernon experiences mild seasonal variation over the course of the year.
The windier part of the year lasts for 7.5 months, from October 8 to May 25, with average wind speeds of more than 5.3 miles per hour. The windiest day of the year is January 15, with an average hourly wind speed of 6.8 miles per hour.
The calmer time of year lasts for 4.5 months, from May 25 to October 8. The calmest day of the year is August 4, with an average hourly wind speed of 3.9 miles per hour.
Average Wind Speed
The predominant average hourly wind direction in Mount Vernon varies throughout the year.
The wind is most often from the south for 2.5 months, from April 9 to June 25 and for 3.2 months, from August 14 to November 19, with a peak percentage of 37% on November 14. The wind is most often from the west for 1.6 months, from June 25 to August 14 and for 4.7 months, from November 19 to April 9, with a peak percentage of 36% on July 20.
The average daily incident shortwave solar energy experiences extreme seasonal variation over the course of the year.
The brighter period of the year lasts for 3.9 months, from April 30 to August 28, with an average daily incident shortwave energy per square meter above 5.8 kWh. The brightest day of the year is July 2, with an average of 6.9 kWh.
The darker period of the year lasts for 3.3 months, from November 4 to February 12, with an average daily incident shortwave energy per square meter below 2.8 kWh. The darkest day of the year is December 19, with an average of 1.7 kWh.
Average Daily Incident Shortwave Solar Energy
For the purposes of this report, the geographical coordinates of Mount Vernon are 40.669 deg latitude, -85.824 deg longitude, and 794 ft elevation.
The topography within 2 miles of Mount Vernon contains only modest variations in elevation, with a maximum elevation change of 108 feet and an average elevation above sea level of 778 feet. Within 10 miles also contains only modest variations in elevation (292 feet). Within 50 miles contains only modest variations in elevation (699 feet).
The area within 2 miles of Mount Vernon is covered by cropland (62%) and trees (27%), within 10 miles by cropland (88%), and within 50 miles by cropland (92%).
This report illustrates the typical weather in Mount Vernon, 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 5 weather stations near enough to contribute to our estimation of the temperature and dew point in Mount Vernon.
For each station, the records are corrected for the elevation difference between that station and Mount Vernon 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 Mount Vernon is computed as the weighted average of the individual contributions from each station, with weights proportional to the inverse of the distance between Mount Vernon and a given station.
The stations contributing to this reconstruction are: Kokomo Municipal Airport (37%, 25 kilometers, southwest); Grissom Air Force Base / Peru (32%, 28 kilometers, west); Fulton County Airport (12%, 53 kilometers, northwest); Delaware County Regional Airport (10%, 61 kilometers, southeast); and Fort Wayne International Airport (10%, 62 kilometers, northeast).
Time zones for aiports and weather stations are provided by AskGeo.com .