Climate and monthly weather forecast
LaSalle, IL

Located in the state of Illinois, USA, LaSalle is categorized under the Dfa classification according to the Köppen climate system. This classification indicates that LaSalle experiences a humid continental climate, without any dry season and having hot summers. Geographically, LaSalle's position contributes significantly to its climate pattern, making it a region with a diverse range of temperatures and varying daylight hours throughout the year.

Analyzing the climate records, it is evident that LaSalle experiences temperature fluctuations with the progression of months. Specifically, the highest average temperatures are reported from June to August ranging from 82°F (27.8°C) to 85°F (29.4°C), while the coldest periods fall between December and February, with temperatures dipping to between 30°F (-1.1°C) and 36°F (2.2°C). On the other hand, the lowest temperatures are seen during the winter months (December through February), falling to between 14°F (-10°C) and 18°F (-7.8°C).

Daylight hours are also subject to change as the year progresses, with the longest daylight hours observed in the Summer months from 14.5 hours in May to a maximum of 15.1 hours in June. The shortest daylight duration falls to 9.2 hours in December.

The range of these conditions creates a diverse climate throughout the year, with temperature and daylight hours variations presenting unique weather patterns associated with each season.

Picking the optimal time to visit LaSalle depends largely on individual preferences regarding weather conditions. However, considering the average temperatures and daylight hours, the period from May to September would arguably present the most favorable conditions. During this period, the temperatures are comfortable, swinging between 62°F (16.7°C) and 83°F (28.3°C) and daylight hours extend from approximately 13.4 to 15.1 hours giving visitors ample time to explore and enjoy the locale.

The period from December to February can be considered the least favorable for visiting LaSalle due to the harsh winter conditions. During these months, temperatures drop to their lowest, averaging between 14°F (-10°C) to 36°F (2.2°C). Additionally, daylight hours are at their shortest during this period, ranging from 9.2 hours in December to 10.6 hours in February, limiting the time available for outdoor activities.

In Spring, from March till May, LaSalle experiences a steady rise in temperature from an average low of 28°F (-2.2°C) in March to a high of 73°F (22.8°C) by the end of May. Daylight hours also increase during this period from 12 hours in March to approximately 14.5 hours in May. This season ushers in transition from the cold of the winter to the warmth of the summer months.

Summer months spanning from June through August are characterized by high temperatures and the longest daylight hours of the year. Average high temperatures range from 82°F (27.8°C) in June up to 85°F (29.4°C) in July before dropping slightly to 83°F (28.3°C) in August. Daylight hours during this period remain above 14 hours, providing ample opportunity for outdoor activities.

Autumn in LaSalle, from September to November, gradually bridges the transition from the hot summer to the colder winter. Temperatures begin at a comfortable high of 77°F (25°C) in September and gradually reduce to 49°F (9.4°C) by November. Daylight hours also decrease gradually during this period from 12.5 hours in September to roughly 9.9 hours by November.

Winter season, from December through February, is marked by the coldest temperatures and shortest daylight hours in LaSalle. Average high temperatures remain below freezing from 30°F (-1.1°C) in December down to 18°F (-7.8°C) in February. Daylight averages range from a minimum of 9.2 hours in December to 10.6 hours in February. Despite the cold, this season paints a magical snowy landscape, making it a unique period to visit.

In the midst of winter, LaSalle, Illinois is subject to brisk temperatures, often seeing a significant decrease compared to the latter part of the year. January is, in fact, the coldest month, with average temperatures ranging from 14°F (-10°C) to 30°F (-1.1°C). Weather in January »

February in LaSalle, Illinois tends not to deviate far from January's chilly disposition, but it does start to gain additional daylight, making for slightly longer days. Although the average temperatures tend to stay between 18°F (-7.8°C) to 36°F (2.2°C) during February, the increment of daylight hours to 10.6 can be refreshing after January's shorter days. Weather in February »

As LaSalle, Illinois moves into March, signs of spring start to appear. A definite warming trend becomes evident when compared to February, with temperatures climbing up to between 28°F (-2.2°C) and 48°F (8.9°C). Newly lengthened days, now totaling 12 hours, lend more sunshine to coax the frozen landscape back to life after winter's slumber. Weather in March »

April in LaSalle, Illinois represents a marked turn from the cooler months into more comfortable temperatures. April brings about moderately warmer conditions, with temperatures spanning from 39°F (3.9°C) to 62°F (16.7°C). This month provides an extended daylight duration of approximately 13.4 hours, noticeably more than the preceding month of March. Weather in April »

As May comes around in LaSalle, Illinois, a truly lively spring environment is set in motion. Average monthly temperatures notably ascend, this time coming up from the colder days of April. May introduces a distinct burst of greenery, and wildlife often becomes increasingly active. Weather in May »

LaSalle, Illinois embraces summer in June. Temperature increases that commenced in May now peak, moving firmly into warm weather territory. An increase to 15.1 hours of daylight illuminates the vibrant summer flora and fauna. As with many Midwestern locations, this time of year offers a host of outdoor activities, from hiking to lakeside relaxation. Weather in June »

In July, LaSalle, Illinois basks in its warmest period. Marked by the year's highest temperatures at 63°F (17.2°C) to 85°F (29.4°C), July stands as the epitome of summer. Long sunshine-filled days of 14.8 hours provide ample opportunity for outdoor exploration or leisure. Weather in July »

August weather in LaSalle, Illinois showcases typical mid-summer features like lengthy days and a slightly cooler touch compared to July. Nevertheless, August's temperatures still hover on the warmer side, reminiscent of the summer's heat. Weather in August »

September in LaSalle, Illinois brings about the start of fall. As the days begin shortening to an average of 12.5 hours, summer's warmth gradually declines, leading to the cooler days of autumn. Colors begin to shift from the vibrant greens of summer to an array of fall hues. Weather in September »

LaSalle, Illinois, dives deeper into the fall season in October with corresponding changes in the weather pattern. The transition away from September's gentler prelude to autumn now evolves into unmistakable fall conditions. October is best known for its colorful foliage and harvests, both of which are shaped by the month's weather patterns. Weather in October »

November in LaSalle, Illinois signifies the arrival of late fall, bringing a chillier climate compared to October. It ushers in shorter 9.9 hour days and the first frosty mornings of the year. While November is devoid of the intense heat of the summer months, it bears its own charm in the form of the late autumn atmosphere. Weather in November »

December marks the onset of winter in LaSalle, Illinois, with a stark contrast to the weather conditions of November. Temperatures steadily dwindle, ranging from 18°F (-7.8°C) to 34°F (1.1°C), embodying the cold essence of the winter season. Weather in December »