Summer Weather in Gurnee Illinois, United StatesDaily high temperatures increase by 5°F, from 72°F to 77°F, rarely falling below 59°F or exceeding 91°F. The highest daily average high temperature is 82°F on July 20. Daily low temperatures increase by 8°F, from 53°F to 60°F, rarely falling below 43°F or exceeding 72°F. The highest daily average low temperature is 64°F on July 27. For reference, on July 19, the hottest day of the year, temperatures in Gurnee typically range from 64°F to 82°F, while on January 29, the coldest day of the year, they range from 16°F to 30°F. Average High and Low Temperature in the Summer in Gurnee
The daily average high (red line) and low (blue line) temperature, with 25th to 75th and 10th to 90th percentile bands. The thin dotted lines are the corresponding average perceived temperatures.
The figure below shows you a compact characterization of the hourly average summer temperatures. 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 the Summer in Gurnee
frigid
15°F
freezing
32°F
very cold
45°F
cold
55°F
cool
65°F
comfortable
75°F
warm
85°F
hot
95°F
sweltering
The average hourly temperature, color coded into bands. The shaded overlays indicate night and civil twilight.
Vernashen, Armenia (6,058 miles away) is the far-away foreign place with temperatures most similar to Gurnee (view comparison). CloudsThe summer in Gurnee experiences rapidly decreasing cloud cover, with the percentage of time that the sky is overcast or mostly cloudy decreasing from 47% to 32%. The lowest chance of overcast or mostly cloudy conditions is 32% on August 28. The clearest day of the summer is August 28, with clear, mostly clear, or partly cloudy conditions 68% of the time. For reference, on December 31, the cloudiest day of the year, the chance of overcast or mostly cloudy conditions is 57%, while on August 28, the clearest day of the year, the chance of clear, mostly clear, or partly cloudy skies is 68%. Cloud Cover Categories in the Summer in Gurnee
0%
clear
20%
mostly clear
40%
partly cloudy
60%
mostly cloudy
80%
overcast
100%
The percentage of time spent in each cloud cover band, categorized by the percentage of the sky covered by clouds.
Compare Gurnee to:PrecipitationA wet day is one with at least 0.04 inches of liquid or liquid-equivalent precipitation. In Gurnee, the chance of a wet day over the course of the summer is rapidly decreasing, starting the season at 36% and ending it at 29%. For reference, the year's highest daily chance of a wet day is 37% on June 13, and its lowest chance is 15% on February 3. RainfallTo show variation within the season and not just the monthly totals, we show the rainfall accumulated over a sliding 31-day period centered around each day. The average sliding 31-day rainfall during the summer in Gurnee is gradually decreasing, starting the season at 3.6 inches, when it rarely exceeds 6.1 inches or falls below 1.4 inches, and ending the season at 3.3 inches, when it rarely exceeds 5.6 inches or falls below 1.3 inches. The highest average 31-day accumulation is 3.6 inches on June 4. Average Monthly Rainfall in the Summer in Gurnee
The average rainfall (solid line) accumulated over the course of a sliding 31-day period centered on the day in question, with 25th to 75th and 10th to 90th percentile bands. The thin dotted line is the corresponding average snowfall.
SunOver the course of the summer in Gurnee, the length of the day is rapidly decreasing. From the start to the end of the season, the length of the day decreases by 1 hour, 54 minutes, implying an average daily decrease of 1 minute, 15 seconds, and weekly decrease of 8 minutes, 44 seconds. The shortest day of the summer is August 31, with 13 hours, 11 minutes of daylight and the longest day is June 21, with 15 hours, 17 minutes of daylight. Hours of Daylight and Twilight in the Summer in Gurnee
The number of hours during which the Sun is visible (black line). From bottom (most yellow) to top (most gray), the color bands indicate: full daylight, twilight (civil, nautical, and astronomical), and full night.
The earliest sunrise of the summer in Gurnee is 5:14 AM on June 14 and the latest sunrise is 1 hour, 2 minutes later at 6:15 AM on August 31. The latest sunset is 8:32 PM on June 27 and the earliest sunset is 1 hour, 6 minutes earlier at 7:27 PM on August 31. Daylight saving time is observed in Gurnee during 2026, but it neither starts nor ends during the summer, so the entire season is in daylight saving time. For reference, on June 21, the longest day of the year, the Sun rises at 5:14 AM and sets 15 hours, 17 minutes later, at 8:32 PM, while on December 21, the shortest day of the year, it rises at 7:17 AM and sets 9 hours, 4 minutes later, at 4:22 PM. Sunrise & Sunset with Twilight in the Summer in Gurnee
The solar day in the summer. From bottom to top, the black lines are the previous solar midnight, sunrise, solar noon, sunset, and the next solar midnight. The day, twilights (civil, nautical, and astronomical), and night are indicated by the color bands from yellow to gray.
The figure below presents a compact representation of the sun's elevation (the angle of the sun above the horizon) and azimuth (its compass bearing) for every hour of every day in the reporting period. The horizontal axis is the day of the year and the vertical axis is the hour of the day. For a given day and hour of that day, the background color indicates the azimuth of the sun at that moment. The black isolines are contours of constant solar elevation. Solar Elevation and Azimuth in the Summer in Gurnee
northeastsouthwest
Solar elevation and azimuth in the the summer of 2026. The black lines are lines of constant solar elevation (the angle of the sun above the horizon, in degrees). The background color fills indicate the azimuth (the compass bearing) of the sun. The lightly tinted areas at the boundaries of the cardinal compass points indicate the implied intermediate directions (northeast, southeast, southwest, and northwest).
MoonThe figure below presents a compact representation of key lunar data for the summer of 2026. 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 the Summer in Gurnee
The time in which the moon is above the horizon (light blue area), with new moons (dark gray lines) and full moons (blue lines) indicated. The shaded overlays indicate night and civil twilight.
HumidityWe base the humidity comfort level on the dew point, as it determines whether perspiration will evaporate from the skin, thereby cooling the body. Lower dew points feel drier and higher dew points feel more humid. Unlike temperature, which typically varies significantly between night and day, dew point tends to change more slowly, so while the temperature may drop at night, a muggy day is typically followed by a muggy night. The chance that a given day will be muggy in Gurnee is rapidly increasing during the summer, rising from 9% to 28% over the course of the season. The highest chance of a muggy day during the summer is 41% on July 27. For reference, on July 27, the muggiest day of the year, there are muggy conditions 41% of the time, while on November 16, the least muggy day of the year, there are muggy conditions 0% of the time. WindThis section discusses the wide-area hourly average wind vector (speed and direction) at 10 meters above the ground. The wind experienced at any given location is highly dependent on local topography and other factors, and instantaneous wind speed and direction vary more widely than hourly averages. The average hourly wind speed in Gurnee is gradually decreasing during the summer, decreasing from 10.2 miles per hour to 9.5 miles per hour over the course of the season. For reference, on January 15, the windiest day of the year, the daily average wind speed is 14.5 miles per hour, while on August 3, the calmest day of the year, the daily average wind speed is 8.6 miles per hour. The lowest daily average wind speed during the summer is 8.6 miles per hour on August 3. The wind direction in Gurnee during the summer is predominantly out of the south from June 1 to July 10 and from August 1 to August 31 and the west from July 10 to August 1. Wind Direction in the Summer in Gurnee
northeastsouthwest
The percentage of hours in which the mean wind direction is from each of the four cardinal wind directions, excluding hours in which the mean wind speed is less than 1.0 mph. The lightly tinted areas at the boundaries are the percentage of hours spent in the implied intermediate directions (northeast, southeast, southwest, and northwest).
Water TemperatureGurnee is located near a large body of water (e.g., ocean, sea, or large lake). This section reports on the wide-area average surface temperature of that water. The average surface water temperature in Gurnee is very rapidly increasing during the summer, rising by 23°F, from 48°F to 71°F, over the course of the season. The highest average surface water temperature during the summer is 72°F on August 14. Growing SeasonDefinitions of the growing season vary throughout the world, but for the purposes of this report, we define it as the longest continuous period of non-freezing temperatures (≥ 32°F) in the year (the calendar year in the Northern Hemisphere, or from July 1 until June 30 in the Southern Hemisphere). The growing season in Gurnee typically lasts for 5.7 months (173 days), from around April 24 to around October 14, rarely starting before April 4 or after May 15, and rarely ending before September 25 or after November 3. The summer in Gurnee is reliably fully within the growing season. Time Spent in Various Temperature Bands and the Growing Season in the Summer in Gurnee
frigid
15°F
freezing
32°F
very cold
45°F
cold
55°F
cool
65°F
comfortable
75°F
warm
85°F
hot
95°F
sweltering
The percentage of time spent in various temperature bands. The black line is the percentage chance that a given day is within the growing season.
Growing degree days are a measure of yearly heat accumulation used to predict plant and animal development, and defined as the integral of warmth above a base temperature, discarding any excess above a maximum temperature. In this report, we use a base of 50°F and a cap of 86°F. The average accumulated growing degree days in Gurnee are very rapidly increasing during the summer, increasing by 1,792°F, from 408°F to 2,200°F, over the course of the season. Solar EnergyThis section discusses the total daily incident shortwave solar energy reaching the surface of the ground over a wide area, taking full account of seasonal variations in the length of the day, the elevation of the Sun above the horizon, and absorption by clouds and other atmospheric constituents. Shortwave radiation includes visible light and ultraviolet radiation. The average daily incident shortwave solar energy in Gurnee is decreasing during the summer, falling by 1.0 kWh, from 6.6 kWh to 5.5 kWh, over the course of the season. The highest average daily incident shortwave solar energy during the summer is 7.0 kWh on July 1. TopographyFor the purposes of this report, the geographical coordinates of Gurnee are 42.370 deg latitude, -87.902 deg longitude, and 676 ft elevation. The topography within 2 miles of Gurnee contains only modest variations in elevation, with a maximum elevation change of 102 feet and an average elevation above sea level of 693 feet. Within 10 miles also contains only modest variations in elevation (285 feet). Within 50 miles contains only modest variations in elevation (755 feet). The area within 2 miles of Gurnee is covered by artificial surfaces (94%), within 10 miles by artificial surfaces (45%) and water (25%), and within 50 miles by water (42%) and cropland (28%). Data SourcesThis report illustrates the typical weather in Gurnee, based on a statistical analysis of historical hourly weather reports and model reconstructions from January 1, 1980 to December 31, 2016. Temperature and Dew PointThere are 2 weather stations near enough to contribute to our estimation of the temperature and dew point in Gurnee. For each station, the records are corrected for the elevation difference between that station and Gurnee 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 Gurnee is computed as the weighted average of the individual contributions from each station, with weights proportional to the inverse of the distance between Gurnee and a given station. The stations contributing to this reconstruction are:
 To get a sense of how much these sources agree with each other, you can view a comparison of Gurnee and the stations that contribute to our estimates of its temperature history and climate. Please note that each source's contribution is adjusted for elevation and the relative change present in the MERRA-2 data. Other DataAll data relating to the Sun's position (e.g., sunrise and sunset) are computed using astronomical formulas from the book, Astronomical Algorithms 2nd Edition , by Jean Meeus. All other weather data, including cloud cover, precipitation, wind speed and direction, and solar flux, come from NASA's MERRA-2 Modern-Era Retrospective Analysis . This reanalysis combines a variety of wide-area measurements in a state-of-the-art global meteorological model to reconstruct the hourly history of weather throughout the world on a 50-kilometer grid. Land Use data comes from the Global Land Cover SHARE database , published by the Food and Agriculture Organization of the United Nations. Elevation data comes from the Shuttle Radar Topography Mission (SRTM) , published by NASA's Jet Propulsion Laboratory. Names, locations, and time zones of places and some airports come from the GeoNames Geographical Database . Time zones for airports and weather stations are provided by AskGeo.com . Maps are © OpenStreetMap contributors. DisclaimerThe information on this site is provided as is, without any assurances as to its accuracy or suitability for any purpose. Weather data is prone to errors, outages, and other defects. We assume no responsibility for any decisions made on the basis of the content presented on this site. We draw particular cautious attention to our reliance on the MERRA-2 model-based reconstructions for a number of important data series. While having the tremendous advantages of temporal and spatial completeness, these reconstructions: (1) are based on computer models that may have model-based errors, (2) are coarsely sampled on a 50 km grid and are therefore unable to reconstruct the local variations of many microclimates, and (3) have particular difficulty with the weather in some coastal areas, especially small islands. We further caution that our travel scores are only as good as the data that underpin them, that weather conditions at any given location and time are unpredictable and variable, and that the definition of the scores reflects a particular set of preferences that may not agree with those of any particular reader. Please review our full terms contained on our Terms of Service page. |
