Climate and monthly weather forecastCrystal Lake, IL
Climate and monthly weather forecast
Weather in January
January, like December, is another subzero cold winter month in Crystal Lake, Illinois, with an average temperature ranging between min 15.1°F (-9.4°C) and max 27°F (-2.8°C). Crystal Lake's January weather, marked by an average high temperature of 27°F (-2.8°C) and an average low temperature of 15.1°F (-9.4°C), is the coldest in the year. Weather in January »Weather in February
The last month of the winter, February, is also a subzero cold month in Crystal Lake, Illinois, with an average temperature ranging between max 30.6°F (-0.8°C) and min 18°F (-7.8°C). Crystal Lake marks the onset of February with an average high-temperature of a still subzero cold 30.6°F (-0.8°C), subtly divergent from January's 27°F (-2.8°C). Weather in February »Weather in March
March, the first month of the spring in Crystal Lake, is a chilly month, with an average temperature ranging between max 43.3°F (6.3°C) and min 29.5°F (-1.4°C). As Crystal Lake, Illinois, welcomes March, the average high-temperature sees a rise, transitioning from a subzero cold 30.6°F (-0.8°C) in February to a frosty 43.3°F (6.3°C). Weather in March »Weather in April
April is a cool spring month in Crystal Lake, Illinois, with an average temperature ranging between min 38.8°F (3.8°C) and max 54.7°F (12.6°C). The average high-temperature increases in April, moving from a frosty 43.3°F (6.3°C) in March to a cool 54.7°F (12.6°C). Weather in April »Weather in May
The last month of the spring, May, is a comfortable month in Crystal Lake, Illinois, with an average temperature fluctuating between 50°F (10°C) and 67.1°F (19.5°C). A shift in the average high-temperature is noticeable in May, changing from a fresh 54.7°F (12.6°C) in April to a refreshing 67.1°F (19.5°C). Weather in May »Weather in June
The first month of the summer, June, is a moderately hot month in Crystal Lake, Illinois, with an average temperature fluctuating between 59°F (15°C) and 76.1°F (24.5°C). The arrival of June brings an increase in high-temperatures, moving from an enjoyable 67.1°F (19.5°C) in May to a moderately hot 76.1°F (24.5°C). Weather in June »Weather in July
July, the same as June, is a moderately hot summer month in Crystal Lake, Illinois, with an average temperature varying between 79.5°F (26.4°C) and 63.1°F (17.3°C). With average high and low temperatures of 79.5°F (26.4°C) and 63.1°F (17.3°C) respectively, July is Crystal Lake's warmest month. Weather in July »Weather in August
The last month of the summer, August, is another warm month in Crystal Lake, Illinois, with an average temperature ranging between min 61.9°F (16.6°C) and max 78.1°F (25.6°C). The beginning of August records an average high-temperature of a still moderately hot 78.1°F (25.6°C), marking a negligible difference from July's 79.5°F (26.4°C). Weather in August »Weather in September
The first month of the autumn, September, is still a pleasant month in Crystal Lake, Illinois, with temperature in the range of an average high of 72.5°F (22.5°C) and an average low of 55°F (12.8°C). In Crystal Lake, entering September brings a subtle temperature decrement, reducing from August's moderately hot 78.1°F (25.6°C) to a pleasant 72.5°F (22.5°C). Weather in September »Weather in October
October, the same as September, in Crystal Lake, Illinois, is a moderate autumn month, with an average temperature ranging between max 59°F (15°C) and min 43.9°F (6.6°C). October's arrival comes with a decrease in the average high-temperature, moving from a pleasant 72.5°F (22.5°C) in September to a refreshing 59°F (15°C). Weather in October »Weather in November
November, the last month of the autumn in Crystal Lake, is also a frosty month, with an average temperature fluctuating between 44.6°F (7°C) and 31.8°F (-0.1°C). November's arrival sees a clear drop in the average high-temperature, decreasing from October's mild 59°F (15°C) to a frosty 44.6°F (7°C). Weather in November »Weather in December
The first month of the winter, December, is also an icy month in Crystal Lake, Illinois, with temperature in the range of an average low of 22.8°F (-5.1°C) and an average high of 32.9°F (0.5°C). During the transition into December, Crystal Lake observes a decrease in the average high-temperature, falling from a chilly 44.6°F (7°C) in November to a cold 32.9°F (0.5°C). Weather in December »Updated: Aug 21, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Crystal Lake, Illinois, reaches its average lowest temperatures in January, measuring 27°F (-2.8°C) at the peak and 15.1°F (-9.4°C) at the lowest.
The months with the highest humidity are January and February, with an average relative humidity of 85%.
In Crystal Lake, during the entire year, the rain falls for 146.9 days and collects up to 21.22" (539mm) of precipitation.
January through May, October through December are months with snowfall.
January is the month with the most snowfall. Snow falls for 12.5 days and accumulates 3.31" (84mm) of snow.
In Crystal Lake, during the entire year, snow falls for 48.7 days and aggregates up to 11.85" (301mm) of snow.
The month with the least sunshine in Crystal Lake is January, with an average of 3.7h of sunshine.
The months with the lowest UV index in Crystal Lake, Illinois, are January and December, with an average maximum UV index of 1.
On Sunday, March 10. 2024, at 2:00 am, Daylight Saving Time starts, and the time zone changes from CST to CDT. Daylight Saving Time ends Sunday, November 3. 2024, at 2:00 am, and the time zone reverts from CDT to CST.
April and October, with an average relative humidity of 76%, are the least humid months.
June is the month with the most rainfall. Rain falls for 16.3 days and accumulates 2.8" (71mm) of precipitation.
In Crystal Lake, snow does not fall in June through September.
The month with the longest days is June, with an average of 15h and 12min of daylight.
Crystal Lake records the warmest temperatures in July, averaging a high of 79.5°F (26.4°C) and a low of 63.1°F (17.3°C).
July has the most sunshine of the year, with an average of 10h of sunshine.
With an average maximum UV index of 6, August is the month with the highest UV index.
The months with the least rainfall are November and December Rain falls for 8 days and accumulates 0.94" (24mm) of rain.
December has the shortest days of the year, with an average of 9h and 12min of daylight.
Average temperature
Crystal Lake, IL
The warmest month (with the highest average high temperature) is July (79.5°F).
The month with the lowest average high temperature is January (27°F).
The month with the highest average low temperature is July (63.1°F).
The coldest month (with the lowest average low temperature) is January (15.1°F).
Average pressure
Crystal Lake, IL
- Average pressure in January:
30.11"Hg - Average pressure in February:
30.1"Hg - Average pressure in March:
30.09"Hg - Average pressure in April:
29.95"Hg - Average pressure in May:
29.96"Hg - Average pressure in June:
29.92"Hg
- Average pressure in July:
29.97"Hg - Average pressure in August:
29.98"Hg - Average pressure in September:
30.03"Hg - Average pressure in October:
30"Hg - Average pressure in November:
30.09"Hg - Average pressure in December:
30.09"Hg
The month with the highest atmospheric pressure is January (30.11"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed
Crystal Lake, IL
- Average wind speed in January:
9.9mph - Average wind speed in February:
9.9mph - Average wind speed in March:
9.5mph - Average wind speed in April:
9.8mph - Average wind speed in May:
8.3mph - Average wind speed in June:
7.2mph
- Average wind speed in July:
6.4mph - Average wind speed in August:
6.2mph - Average wind speed in September:
7.1mph - Average wind speed in October:
8.7mph - Average wind speed in November:
9.4mph - Average wind speed in December:
9.3mph
The windiest months (with the highest average wind speed) are January and February (9.9mph).
The calmest month (with the lowest average wind speed) is August (6.2mph).
Average humidity
Crystal Lake, IL
The months with the highest relative humidity are January and February (85%).
The months with the lowest relative humidity are April and October (76%).
Average rainfall
Crystal Lake, IL
- Average rainfall in January:
1.1" - Average rainfall in February:
1.1" - Average rainfall in March:
1.22" - Average rainfall in April:
2.56" - Average rainfall in May:
2.52" - Average rainfall in June:
2.8"
- Average rainfall in July:
2.32" - Average rainfall in August:
2.52" - Average rainfall in September:
1.46" - Average rainfall in October:
1.73" - Average rainfall in November:
0.94" - Average rainfall in December:
0.94"
The wettest month (with the highest rainfall) is June (2.8").
The driest months (with the least rainfall) are November and December (0.94").
Average rainfall days
Crystal Lake, IL
- Average rainfall days in January:
5.5 days - Average rainfall days in February:
4.8 days - Average rainfall days in March:
11.5 days - Average rainfall days in April:
15.1 days - Average rainfall days in May:
17.1 days - Average rainfall days in June:
16.3 days
- Average rainfall days in July:
18.5 days - Average rainfall days in August:
17.3 days - Average rainfall days in September:
12 days - Average rainfall days in October:
12.9 days - Average rainfall days in November:
8 days - Average rainfall days in December:
7.9 days
The month with the highest number of rainy days is July (18.5 days).
The month with the least rainy days is February (4.8 days).
Average snowfall
Crystal Lake, IL
- Average snowfall in January:
3.31" - Average snowfall in February:
2.52" - Average snowfall in March:
1.34" - Average snowfall in April:
1.5" - Average snowfall in May:
0.08" - Average snowfall in June:
0"
The month with the highest snowfall is January (3.31").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days
Crystal Lake, IL
- Average snowfall days in January:
12.5 days - Average snowfall days in February:
10.7 days - Average snowfall days in March:
7.5 days - Average snowfall days in April:
2.2 days - Average snowfall days in May:
0.2 days - Average snowfall days in June:
0 days
- Average snowfall days in July:
0 days - Average snowfall days in August:
0 days - Average snowfall days in September:
0 days - Average snowfall days in October:
0.7 days - Average snowfall days in November:
4 days - Average snowfall days in December:
10.9 days
The month with the highest number of snowfall days is January (12.5 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight / Average sunshine
Crystal Lake, IL
- Average daylight in January:
9h and 30min - Average daylight in February:
10h and 36min - Average daylight in March:
12h and 0min - Average daylight in April:
13h and 24min - Average daylight in May:
14h and 36min - Average daylight in June:
15h and 12min
- Average daylight in July:
14h and 54min - Average daylight in August:
13h and 48min - Average daylight in September:
12h and 30min - Average daylight in October:
11h and 6min - Average daylight in November:
9h and 48min - Average daylight in December:
9h and 12min
The month with the longest days is June (Average daylight: 15h and 12min).
The month with the shortest days is December (Average daylight: 9h and 12min).
- Average sunshine in January:
3h and 42min - Average sunshine in February:
3h and 48min - Average sunshine in March:
6h and 0min - Average sunshine in April:
7h and 30min - Average sunshine in May:
8h and 30min - Average sunshine in June:
9h and 42min
- Average sunshine in July:
10h and 0min - Average sunshine in August:
9h and 48min - Average sunshine in September:
8h and 48min - Average sunshine in October:
5h and 30min - Average sunshine in November:
5h and 6min - Average sunshine in December:
3h and 54min
The month with the most sunshine is July (Average sunshine: 10h and 0min).
The month with the least sunshine is January (Average sunshine: 3h and 42min).
Average sunshine days
Crystal Lake, IL
- Average sunshine days in January:
14.4 days - Average sunshine days in February:
12.3 days - Average sunshine days in March:
14.3 days - Average sunshine days in April:
11.3 days - Average sunshine days in May:
10.7 days - Average sunshine days in June:
10.7 days
- Average sunshine days in July:
10 days - Average sunshine days in August:
10.4 days - Average sunshine days in September:
14.2 days - Average sunshine days in October:
15.4 days - Average sunshine days in November:
17.3 days - Average sunshine days in December:
16.2 days
The month with the most sunshine days is November (17.3 days).
The month with the least sunshine days is July (10 days).
Average UV index
Crystal Lake, IL
The month with the highest UV index is August (UV index 6).
The months with the lowest UV index are January and December (UV index 1).
Average cloud cover
Crystal Lake, IL
The month with the most cloud cover is January (Cloud cover 62).
The months with the least cloud cover are July and September (Cloud cover 32).
Average visibility
Crystal Lake, IL
The months with the highest visibility are March, April, May, June, July, September, October, November and December (6mi).
The months with the lowest visibility are January, February and August (5mi).
