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February Weather in Crystal Lake Illinois, United States

Daily high temperatures increase by 9°F, from 29°F to 38°F, rarely falling below 14°F or exceeding 54°F.

Daily low temperatures increase by 8°F, from 15°F to 23°F, rarely falling below -4°F or exceeding 36°F.

For reference, on July 18, the hottest day of the year, temperatures in Crystal Lake typically range from 64°F to 83°F, while on January 22, the coldest day of the year, they range from 15°F to 29°F.

Average High and Low Temperature in February in Crystal Lake

Average High and Low Temperature in February in Crystal LakeFeb11223344556677889910101111121213131414151516161717181819192020212122222323242425252626272728282929-10°F-10°F0°F0°F10°F10°F20°F20°F30°F30°F40°F40°F50°F50°F60°F60°F70°F70°FJanMarFeb 129°FFeb 129°F15°F15°FFeb 2938°FFeb 2938°F23°F23°FFeb 1132°FFeb 1132°F18°F18°FFeb 2135°FFeb 2135°F20°F20°F
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 temperatures for the quarter of the year centered on February. 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 February in Crystal Lake

Average Hourly Temperature in February in Crystal LakeFeb1122334455667788991010111112121313141415151616171718181919202021212222232324242525262627272828292912 AM12 AM2 AM2 AM4 AM4 AM6 AM6 AM8 AM8 AM10 AM10 AM12 PM12 PM2 PM2 PM4 PM4 PM6 PM6 PM8 PM8 PM10 PM10 PM12 AM12 AMJanMarfreezingvery coldcold
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.

Garrni, Armenia (6,040 miles away) is the far-away foreign place with temperatures most similar to Crystal Lake (view comparison).

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The month of February in Crystal Lake experiences essentially constant cloud cover, with the percentage of time that the sky is overcast or mostly cloudy remaining about 56% throughout the month.

The clearest day of the month is February 25, with clear, mostly clear, or partly cloudy conditions 46% of the time.

For reference, on December 30, the cloudiest day of the year, the chance of overcast or mostly cloudy conditions is 58%, while on August 25, the clearest day of the year, the chance of clear, mostly clear, or partly cloudy skies is 68%.

Cloud Cover Categories in February in Crystal Lake

Cloud Cover Categories in February in Crystal LakeFeb112233445566778899101011111212131314141515161617171818191920202121222223232424252526262727282829290%100%10%90%20%80%30%70%40%60%50%50%60%40%70%30%80%20%90%10%100%0%JanMarFeb 144%Feb 144%Feb 2945%Feb 2945%Feb 1143%Feb 1143%Feb 2145%Feb 2145%clearmostly clearpartly cloudymostly cloudyovercast
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.

A wet day is one with at least 0.04 inches of liquid or liquid-equivalent precipitation. In Crystal Lake, the chance of a wet day over the course of February is increasing, starting the month at 14% and ending it at 18%.

For reference, the year's highest daily chance of a wet day is 38% on May 23, and its lowest chance is 14% on February 2.

Over the course of February in Crystal Lake, the chance of a day with only rain increases from 4% to 10%, the chance of a day with mixed snow and rain remains an essentially constant 3% throughout, and the chance of a day with only snow decreases from 7% to 5%.

Probability of Precipitation in February in Crystal Lake

The percentage of days in which various types of precipitation are observed, excluding trace quantities: rain alone, snow alone, and mixed (both rain and snow fell in the same day).

Rainfall

To show variation within the month and not just the monthly total, we show the rainfall accumulated over a sliding 31-day period centered around each day.

The average sliding 31-day rainfall during February in Crystal Lake is gradually increasing, starting the month at 0.6 inches, when it rarely exceeds 1.6 inches or falls below -0.0 inches, and ending the month at 1.1 inches, when it rarely exceeds 2.3 inches or falls below 0.1 inches.

Average Monthly Rainfall in February in Crystal Lake

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.

Snowfall

As with rainfall, we consider the snowfall accumulated over a sliding 31-day period centered around each day.

The average sliding 31-day snowfall during February in Crystal Lake is gradually decreasing, starting the month at 4.7 inches, when it rarely exceeds 9.9 inches or falls below 0.7 inches, and ending the month at 3.9 inches, when it rarely exceeds 8.6 inches or falls below 0.2 inches.

Average Monthly Snowfall in February in Crystal Lake

The average snowfall (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 rainfall.

Over the course of February in Crystal Lake, 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, 13 minutes, implying an average daily increase of 2 minutes, 37 seconds, and weekly increase of 18 minutes, 21 seconds.

The shortest day of the month is February 1, with 10 hours, 0 minutes of daylight and the longest day is February 29, with 11 hours, 14 minutes of daylight.

Hours of Daylight and Twilight in February in Crystal Lake

Hours of Daylight and Twilight in February in Crystal LakeFeb112233445566778899101011111212131314141515161617171818191920202121222223232424252526262727282829290 hr24 hr4 hr20 hr8 hr16 hr12 hr12 hr16 hr8 hr20 hr4 hr24 hr0 hrJanMarnightnightdaydayFeb 110 hr, 0 minFeb 110 hr, 0 minFeb 2911 hr, 14 minFeb 2911 hr, 14 min
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 latest sunrise of the month in Crystal Lake is 7:06 AM on February 1 and the earliest sunrise is 38 minutes earlier at 6:29 AM on February 29.

The earliest sunset is 5:07 PM on February 1 and the latest sunset is 36 minutes later at 5:42 PM on February 29.

Daylight saving time is observed in Crystal Lake during 2024, but it neither starts nor ends during February, so the entire month is in standard time.

For reference, on June 20, the longest day of the year, the Sun rises at 5:16 AM and sets 15 hours, 16 minutes later, at 8:33 PM, while on December 21, the shortest day of the year, it rises at 7:19 AM and sets 9 hours, 5 minutes later, at 4:24 PM.

Sunrise & Sunset with Twilight and Daylight Saving Time in February in Crystal Lake

Sunrise & Sunset with Twilight and Daylight Saving Time in February in Crystal LakeFeb1122334455667788991010111112121313141415151616171718181919202021212222232324242525262627272828292912 AM2 AM4 AM6 AM8 AM10 AM12 PM2 PM4 PM6 PM8 PM10 PM12 AMJanMar6:29 AM6:29 AMFeb 295:42 PMFeb 295:42 PM7:06 AM7:06 AMFeb 15:07 PMFeb 15:07 PM6:55 AM6:55 AMFeb 115:20 PMFeb 115:20 PMSolarMidnightSolarMidnightSolarNoonSunriseSunset
The solar day over the course of February. 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 February in Crystal Lake

Solar Elevation and Azimuth in February in Crystal LakeFeb1122334455667788991010111112121313141415151616171718181919202021212222232324242525262627272828292912 AM12 AM2 AM2 AM4 AM4 AM6 AM6 AM8 AM8 AM10 AM10 AM12 PM12 PM2 PM2 PM4 PM4 PM6 PM6 PM8 PM8 PM10 PM10 PM12 AM12 AMJanMar0010102020203030405000010102020303040
northeastsouthwest
Solar elevation and azimuth over the course of February 2024. 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).

The figure below presents a compact representation of key lunar data for February 2024. 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 February in Crystal Lake

Moon Rise, Set & Phases in February in Crystal LakeFeb1122334455667788991010111112121313141415151616171718181919202021212222232324242525262627272828292912 AM12 AM4 AM4 AM8 AM8 AM12 PM12 PM4 PM4 PM8 PM8 PM12 AM12 AMJanMarJan 115:58 AMJan 115:58 AMJan 2511:55 AMJan 2511:55 AMFeb 95:00 PMFeb 95:00 PMFeb 246:31 AMFeb 246:31 AMMar 104:01 AMMar 104:01 AMMar 252:01 AMMar 252:01 AM7:57 AM7:57 AM4:48 PM4:48 PM3:44 PM3:44 PM7:38 AM7:38 AM7:10 AM7:10 AM5:01 PM5:01 PM4:50 PM4:50 PM6:59 AM6:59 AM7:32 AM7:32 AM7:34 PM7:34 PM6:47 PM6:47 PM7:00 AM7:00 AM
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.
Feb 2024IlluminationMoonriseMoonsetMoonriseMeridian PassingDistance
1
65%-10:06 AMWSW-4:36 AMS249,045 mi
2
50%12:07 AMESE10:28 AMWSW-5:18 AMS246,552 mi
3
45%1:14 AMESE10:55 AMWSW-6:05 AMS243,380 mi
4
34%2:23 AMESE11:28 AMSW-6:56 AMS239,669 mi
5
24%3:34 AMSE12:12 PMSW-7:53 AMS235,642 mi
6
15%4:41 AMSE1:08 PMSW-8:55 AMS231,609 mi
7
7%5:41 AMSE2:18 PMSW-10:00 AMS227,940 mi
8
2%6:31 AMSE3:38 PMWSW-11:04 AMS225,012 mi
9
0%7:10 AMESE5:01 PMWSW-12:06 PMS223,139 mi
10
1%7:42 AMESE6:25 PMWSW-1:03 PMS222,504 mi
11
5%8:09 AME7:45 PMW-1:56 PMS223,134 mi
12
12%8:33 AME9:04 PMW-2:46 PMS224,900 mi
13
21%8:56 AME10:21 PMWNW-3:35 PMS227,557 mi
14
32%9:20 AMENE11:37 PMWNW-4:24 PMS230,797 mi
15
43%9:46 AMENE--5:14 PMS234,309 mi
16
50%-12:52 AMWNW10:17 AMENE6:06 PMS237,815 mi
17
65%-2:04 AMNW10:55 AMNE7:00 PMS241,105 mi
18
75%-3:12 AMNW11:41 AMNE7:55 PMS244,036 mi
19
83%-4:11 AMNW12:35 PMNE8:49 PMS246,533 mi
20
90%-5:00 AMNW1:36 PMNE9:41 PMS248,573 mi
21
95%-5:40 AMNW2:40 PMENE10:30 PMS250,165 mi
22
98%-6:11 AMWNW3:45 PMENE11:16 PMS251,332 mi
23
100%-6:37 AMWNW4:50 PMENE11:58 PMS252,091 mi
24
100%-6:59 AMWNW5:52 PMENE--
25
100%-7:18 AMW6:53 PME12:38 AMS252,445 mi
26
97%-7:35 AMW7:54 PME1:17 AMS252,372 mi
27
93%-7:53 AMW8:55 PME1:55 AMS251,833 mi
28
88%-8:11 AMWSW9:58 PMESE2:34 AMS250,775 mi
29
80%-8:32 AMWSW11:03 PMESE3:15 AMS249,148 mi

We 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 Crystal Lake is essentially constant during February, remaining around 0% throughout.

For reference, on July 21, the muggiest day of the year, there are muggy conditions 40% 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 February in Crystal Lake

Humidity Comfort Levels in February in Crystal LakeFeb112233445566778899101011111212131314141515161617171818191920202121222223232424252526262727282829290%0%10%10%20%20%30%30%40%40%50%50%60%60%70%70%80%80%90%90%100%100%JanMarFeb 150%Feb 150%Feb 10%Feb 10%Feb 290%Feb 290%drydry
dry 55°F comfortable 60°F humid 65°F muggy 70°F oppressive 75°F miserable
The percentage of time spent at various humidity comfort levels, categorized by dew point.

This 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 Crystal Lake is essentially constant during February, remaining within 0.1 miles per hour of 12.5 miles per hour throughout.

For reference, on January 15, the windiest day of the year, the daily average wind speed is 12.7 miles per hour, while on August 2, the calmest day of the year, the daily average wind speed is 7.9 miles per hour.

The lowest daily average wind speed during February is 12.4 miles per hour on February 13.

Average Wind Speed in February in Crystal Lake

The average of mean hourly wind speeds (dark gray line), with 25th to 75th and 10th to 90th percentile bands.

The hourly average wind direction in Crystal Lake throughout February is predominantly from the west, with a peak proportion of 41% on February 1.

Wind Direction in February in Crystal Lake

Wind Direction in February in Crystal LakeWNFeb112233445566778899101011111212131314141515161617171818191920202121222223232424252526262727282829290%100%20%80%40%60%60%40%80%20%100%0%JanMarwestsoutheastnorth
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).

Crystal Lake 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 Crystal Lake is essentially constant during February, remaining within 1°F of 36°F throughout.

The lowest average surface water temperature during February is 35°F on February 29.

Average Water Temperature in February in Crystal Lake

Average Water Temperature in February in Crystal LakeFeb1122334455667788991010111112121313141415151616171718181919202021212222232324242525262627272828292933°F33°F34°F34°F35°F35°F36°F36°F37°F37°F38°F38°F39°F39°F40°F40°F41°F41°F42°F42°FJanMarFeb 2935°FFeb 2935°FFeb 137°FFeb 137°FFeb 1136°FFeb 1136°FFeb 2136°FFeb 2136°F
The daily average water temperature (purple line), with 25th to 75th and 10th to 90th percentile bands.

Definitions 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 Crystal Lake typically lasts for 5.5 months (168 days), from around April 26 to around October 11, rarely starting before April 8 or after May 14, and rarely ending before September 23 or after October 28.

The month of February in Crystal Lake is reliably fully outside of the growing season.

Time Spent in Various Temperature Bands and the Growing Season in February in Crystal Lake

Time Spent in Various Temperature Bands and the Growing Season in February in Crystal LakeFeb112233445566778899101011111212131314141515161617171818191920202121222223232424252526262727282829290%100%10%90%20%80%30%70%40%60%50%50%60%40%70%30%80%20%90%10%100%0%JanMar0%Feb 150%Feb 15frigidfreezingvery coldcoldcool
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 Crystal Lake are essentially constant during February, remaining within 2°F of 3°F throughout.

Growing Degree Days in February in Crystal Lake

The average growing degree days accumulated over the course of February, with 25th to 75th and 10th to 90th percentile bands.

This 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 Crystal Lake is increasing during February, rising by 1.0 kWh, from 2.4 kWh to 3.4 kWh, over the course of the month.

Average Daily Incident Shortwave Solar Energy in February in Crystal Lake

Average Daily Incident Shortwave Solar Energy in February in Crystal LakeFeb112233445566778899101011111212131314141515161617171818191920202121222223232424252526262727282829290 kWh0 kWh1 kWh1 kWh2 kWh2 kWh3 kWh3 kWh4 kWh4 kWh5 kWh5 kWh6 kWh6 kWhJanMarFeb 12.4 kWhFeb 12.4 kWhFeb 293.4 kWhFeb 293.4 kWhFeb 112.7 kWhFeb 112.7 kWh
The average daily shortwave solar energy reaching the ground per square meter (orange line), with 25th to 75th and 10th to 90th percentile bands.

For the purposes of this report, the geographical coordinates of Crystal Lake are 42.241 deg latitude, -88.316 deg longitude, and 912 ft elevation.

The topography within 2 miles of Crystal Lake contains only modest variations in elevation, with a maximum elevation change of 135 feet and an average elevation above sea level of 901 feet. Within 10 miles also contains only modest variations in elevation (308 feet). Within 50 miles contains only modest variations in elevation (745 feet).

The area within 2 miles of Crystal Lake is covered by artificial surfaces (80%) and trees (11%), within 10 miles by cropland (41%) and artificial surfaces (36%), and within 50 miles by cropland (51%) and artificial surfaces (25%).

This report illustrates the typical weather in Crystal Lake, 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 6 weather stations near enough to contribute to our estimation of the temperature and dew point in Crystal Lake.

For each station, the records are corrected for the elevation difference between that station and Crystal Lake 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 Crystal Lake is computed as the weighted average of the individual contributions from each station, with weights proportional to the inverse of the distance between Crystal Lake 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 Crystal Lake 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 Data

All 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.

Disclaimer

The 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.

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